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Keywords:

  • nutritional requirements;
  • overweight and obesity;
  • physical activity;
  • school food standards;
  • schoolchildren

Summary

  1. Top of page
  2. Summary
  3. Introduction
  4. Nutritional requirements of schoolchildren
  5. Findings of the National Diet and Nutrition Surveys (NDNS)
  6. Nutrition and health in childhood
  7. Food provision in school
  8. Food in the curriculum
  9. Selected initiatives and organisations of relevance to child nutrition
  10. Acknowledgement
  11. Conflict of interest
  12. References

This paper updates a British Nutrition Foundation (BNF) Briefing Paper on this topic, published in 2011. Healthy eating and being physically active are particularly important for children and adolescents. This is because their nutrition and lifestyle influence their wellbeing, growth and development. There remains considerable room for improvement in the diets of British schoolchildren, according to findings of the government's National Diet and Nutrition Surveys (NDNS), but some improvements have been made in the past decade. Although intakes of saturated fatty acids and non-milk extrinsic sugars have decreased in recent years, on average, they are still above recommended upper levels. Average contribution of fat to total energy intake has dropped below the recommended upper level of 35%, but fibre intakes remain low. With regard to micronutrients, many teenage girls are consuming low amounts of iron, but there is also evidence of low intakes of vitamin A, riboflavin, calcium, magnesium, potassium, selenium, iodine and zinc. New data on micronutrient status is now available for 11–18 year-olds, and reveals low levels of vitamin D, riboflavin and iron (mainly in girls). Low vitamin D intake and status is a particular problem in some ethnic minority groups, especially South Asian children. There is also some evidence of socio-economic inequalities; for example, children from families with higher incomes tend to have higher intakes of fruits and vegetables compared with children from families with lower incomes. This paper also discusses how dietary patterns can influence the micronutrient intake and status of schoolchildren, as well as the risk of overweight and obesity.

Since publication of the Briefing Paper in 2011, new physical activity guidelines have been published and, for the first time, these are UK-wide guidelines. Also for the first time, UK-wide data on physical activity levels in schoolchildren are available (for 7-year-old children). Physical activity levels vary little between the UK regions, with the exception of Northern Ireland where fewer children meet the UK recommendations than in other regions. The data highlight significant differences between boys and girls (with girls generally being less active) and significant differences between ethnic groups. In particular, children from the Bangladeshi, Indian and Pakistani ethnic groups are less likely to meet the recommended levels of physical activity compared with other children.

Obesity remains a major problem among British schoolchildren and there is a stark socio-economic gradient, with levels of obesity being highest in the most socially deprived children.

This paper also discusses various health issues in children, including iron deficiency anaemia, oral health, bone development, food allergy and intolerance, and cognitive function in children, updating the previous paper with the latest statistics and evidence.

The findings of the NDNS serve to emphasise the importance of a whole school approach to good nutrition embracing the school curriculum as well as the food and drink available in schools (as highlighted in the recently published School Food Plan). School food provision has seen many changes over recent years, with school food standards now in place in all UK regions, most recently Wales. Various evaluations of the impact of school food standards, mainly in England, have highlighted improvements in the diets of schoolchildren, not only in the school setting but in their diets overall. However, there remains room for improvement. This paper also briefly describes a selection of initiatives and organisations of relevance to child nutrition.


Introduction

  1. Top of page
  2. Summary
  3. Introduction
  4. Nutritional requirements of schoolchildren
  5. Findings of the National Diet and Nutrition Surveys (NDNS)
  6. Nutrition and health in childhood
  7. Food provision in school
  8. Food in the curriculum
  9. Selected initiatives and organisations of relevance to child nutrition
  10. Acknowledgement
  11. Conflict of interest
  12. References

In recent years there has been increasing focus on improving children's diet and lifestyle habits as part of an overall strategy for preventing obesity and chronic diseases such as cardiovascular disease (CVD), type 2 diabetes and osteoporosis. This has been driven by evidence that many chronic diseases have their roots in the early years and that healthy behaviours in childhood and the teenage years set patterns for later life. It is also well recognised that more needs to be done to improve children's health in the UK and in particular their diet and lifestyle habits (Chief Medical Officer 2013). This paper updates a BNF Briefing Paper on the topic of nutrition, health and schoolchildren, published in 2011 (see Weichselbaum & Buttriss 2011). It reviews what we know about current dietary and lifestyle habits of school-aged children in the UK and considers the impacts of these habits on short- and long-term health.

Nutritional requirements of schoolchildren

  1. Top of page
  2. Summary
  3. Introduction
  4. Nutritional requirements of schoolchildren
  5. Findings of the National Diet and Nutrition Surveys (NDNS)
  6. Nutrition and health in childhood
  7. Food provision in school
  8. Food in the curriculum
  9. Selected initiatives and organisations of relevance to child nutrition
  10. Acknowledgement
  11. Conflict of interest
  12. References

It has long been recognised that good nutrition is of crucial importance for the wellbeing, growth and development of children. Even though the energy cost of growth is a minor component of total energy requirements, growth rate is a sensitive indicator of overall dietary adequacy (Butte 2000). The nutritional requirements (in addition to energy) of children and adolescents are high in relation to their size because of the demands for growth, in addition to requirements for tissue maintenance and physical activity. In the longer term, food patterns in childhood, particularly adolescence, can set the scene for future dietary preferences and eating behaviour in adult life. There is also substantial evidence that poor diet and poor physical activity patterns in childhood can lead to problems that manifest later in life, particularly in relation to heart disease, obesity, type 2 diabetes, osteoporosis and some forms of cancer.

Energy and nutrient requirements

Children's energy and nutrient requirements are relatively high in relation to their body size, especially during periods of rapid growth. For example, during adolescence (10–18 years), puberty is associated with increased requirements for energy and nutrients as illustrated in Tables 1, 2a and 2b, because of the hormonally driven rate of increase in height and weight. In boys, the linear growth spurt resulting in increased height is greater than in girls and is accompanied by an increase in muscle growth. Concurrently, the physiologically driven rapid increase in bone mass is accompanied by deposition of calcium and phosphate (see section ‘Bone development’).

Table 1. Estimated average requirement (EAR) values for energy for children and adolescents aged 4–18 years, expressed as megajoules (MJ)/day (with kcal/day in brackets)
Age (years)BoysGirls
Less activePopulation averageMore activeLess activePopulation averageMore active
MJ/day (kcal/day)MJ/day (kcal/day)MJ/day (kcal/day)MJ/day (kcal/day)MJ/day (kcal/day)MJ/day (kcal/day)
Source: SACN 2011.
 45.3 (1267)5.8 (1386)6.3 (1506)4.9 (1171)5.4 (1291)5.8 (1386)
 55.6 (1338)6.2 (1482)6.6 (1577)5.2 (1243)5.7 (1362)6.2 (1482)
 65.9 (1410)6.6 (1577)7.1 (1697)5.6 (1338)6.2 (1482)6.6 (1577)
 76.2 (1482)6.9 (1649)7.4 (1769)5.8 (1386)6.4 (1530)6.9 (1649)
 86.6 (1577)7.3 (1745)7.9 (1888)6.2 (1482)6.8 (1625)7.4 (1769)
 97.0 (1673)7.7 (1840)8.3 (1984)6.5 (1554)7.2 (1721)7.8 (1864)
108.1 (1936)8.5 (2032)9.0 (2151)7.8 (1864)8.1 (1936)8.6 (2055)
118.5 (2032)8.9 (2127)9.5 (2271)8.1 (1936)8.5 (2032)9.0 (2151)
129.0 (2151)9.4 (2247)10.0 (2390)8.5 (2032)8.8 (2103)9.4 (2247)
139.7 (2318)10.1 (2414)10.8 (2581)9.0 (2151)9.3 (2223)10.0 (2390)
1410.5 (2510)11.0 (2629)11.7 (2796)9.4 (2247)9.8 (2342)10.4 (2486)
1511.3 (2701)11.8 (2820)12.6 (3011)9.6 (2294)10.0 (2390)10.6 (2533)
1611.9 (2844)12.4 (2964)13.2 (3155)9.7 (2318)10.1 (2414)10.8 (2581)
1712.3 (2940)12.9 (3083)13.7 (3274)9.8 (2342)10.3 (2462)10.9 (2605)
1812.6 (3011)13.2 (3155)14.0 (3346)9.9 (2366)10.3 (2462)11.0 (2629)
Table 2a. UK dietary reference values for boys aged 4–18 years, expressed as reference nutrient intakes (RNIs)
Age (years)4–67–1011–1415–18
Source: DH 1991.
Protein, g19.728.342.155.2
Iron, mg6.18.711.311.3
Calcium, mg45055010001000
Zinc, mg6.57.09.09.5
Magnesium, mg120200280300
Phosphorus, mg350450775775
Sodium, mg700120016001600
Vitamin A, μg400500600700
Vitamin B1 (thiamin), mg0.70.70.91.1
Vitamin B2 (riboflavin), mg0.81.01.21.3
Niacin, mg11121518
Vitamin B6, mg0.91.01.21.5
Vitamin B12, μg0.81.01.21.5
Folate, μg100150200200
Vitamin C, mg30303540
Table 2b. UK dietary reference values for girls aged 4–18 years, expressed as reference nutrient intakes (RNIs)
Age (years)4–67–1011–1415–18
Source: DH 1991.
Protein, g19.728.341.245.0
Iron, mg6.18.714.814.8
Calcium, mg450550800800
Zinc, mg6.57.09.07.0
Magnesium, mg120200280300
Phosphorus, mg350450625625
Sodium, mg700120016001600
Vitamin A, μg400500600600
Vitamin B1 (thiamin), mg0.70.70.70.8
Vitamin B2 (riboflavin), mg0.81.01.11.1
Niacin, mg11121214
Vitamin B6, mg0.91.01.01.2
Vitamin B12, μg0.81.01.21.5
Folate, μg100150200200
Vitamin C, mg30303540

Height attained and associated growth rate varies within the population and the Health Survey for England in 2004, which focused on minority ethnic groups, highlighted differences in average height between ethnic groups as well as in comparison with the general population (see Fig. 1) (Becker et al. 2006).

figure

Figure 1. Average height of children aged 2–15 years living in England in 2004, by minority ethnic group and sex.

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Dietary reference values (DRVs)

DRVs are estimates of the requirements of energy and nutrients for groups of people, taking into account various factors that influence requirements including growth and development. DRVs are useful as a general guide for a whole population group, but they are not intended for the assessment of the needs of individuals. Examples of their use include interpreting outcomes of dietary surveys to detect low intake levels of population groups, setting standards for food provision, and planning meals in schools or hospitals. DRVs for a given nutrient comprise: (1) the estimated average equirement (EAR), which is an estimate of the average requirement for energy or a nutrient – approximately 50% of a group of people will require less, and 50% will require more; (2) the reference nutrient intake (RNI), which is the amount of a nutrient that is enough to ensure that the needs of nearly all the group (97.5%) are being met; and (3) the lower reference nutrient intake (LRNI), which is the amount of a nutrient that is enough for only the small percentage of the group (2.5%) who have low requirements.

Typically, DRVs for protein, vitamins and minerals for groups of children are expressed as RNIs. For energy, EARs are used as an indication of requirements. Use of RNI values (equivalent to the mean plus 2 standard deviations) is not suitable for energy, as this would mean that predicted intakes would be greater than most people's needs and hence would result in weight gain over a period of time. Energy requirements are influenced by physical activity levels, in particular, and can vary significantly depending on the amount of physical activity undertaken habitually. Guidelines for energy intake assume a sedentary lifestyle, as this is the situation for the majority of people in Britain, although increased activity is advised. DRVs for macronutrients are expressed in terms of food (or total) energy intake and again are population mean values rather than recommendations for individuals.

The reference values for energy intake in the UK have recently been updated by the Scientific Advisory Committee on Nutrition (SACN), using data from studies that are representative of the current UK population and that have employed the doubly-labelled water method, an objective method for measuring energy requirements that was not in use in the 1980s/early 1990s when the previous reference values were set (SACN 2011). The population EAR values are calculated at median physical activity level values for best estimates of healthy bodyweights, i.e. the 50th centiles of the UK/World Health Organization (WHO) Growth Standards (2–4 years) and the UK 1990 reference for children and adolescents (for children over 4 years of age) (also see section ‘Overweight and Obesity’). These reference weights are about 15% lower than current UK weights and thus for those children who are overweight and for any underweight children, energy intakes at the recommended levels will be associated with weight change (SACN 2011). The new EARs for younger children are lower than the EARs published in 1991, whereas for children older than 10 years, they are now higher. See Table 1 for EARs for energy for children and adolescents. These values reflect the findings of recent studies and highlight increasing requirements with age, differences between boys and girls, which become more pronounced with age, and differences in requirements between less active and more active (compared with the population average) children and adolescents.

Tables 2a and 2b show the current UK DRVs for selected nutrients for boys and girls aged 4–18 years, respectively (DH 1991). Desirable intakes of carbohydrates and fats are available for the population in general and are expressed as a proportion of total dietary energy (Table 3). These take into account eating habits in the UK and the practical implications of dietary changes in line with those considered desirable for health. They have been calculated with the needs of the adult population in mind. While these values provide a useful guide for older (school age) children, the recommendation for fat, in particular, should not be applied in full to the diets of pre-school children especially where appetite is poor.

Table 3. Dietary reference values for macronutrients, for the population in general, i.e. all ages (% food energy)
  1. *Non-milk extrinsic sugars.

Source: DH 1991.
Fat35
of which saturates11
Carbohydrate50
of which starch, intrinsic sugars and milk sugars39
of which NMES*11

There are no specific UK figures for the desirable amount of dietary fibre (non-starch polysaccharide, NSP) for children. The Department of Health recommends that children should have proportionally lower fibre intakes than adults; the current UK DRV for adults is 18 g of NSP per day as measured by the Englyst method (DH 1991). This equates to approximately 24 g if the Association of Official Analytical Chemists (AOAC) method is used (Lunn & Buttriss 2007).

SACN is currently reviewing the scientific evidence and associated dietary recommendations for fibre (as well as for carbohydrates in general); a report is expected in 2014. Meanwhile, the European Food Safety Authority (EFSA) has defined fibre as non-digestible carbohydrates (including NSP, resistant oligosaccharides, resistant starch) plus lignin (EFSA 2007, 2010a). This definition is in accordance with methods of analysis approved by the AOAC. EFSA's definition of fibre has been adopted by the European Commission as the basis of fibre declarations on food packaging in Europe (EC 2008). EFSA's recommended intake level for adults is 25 g per day. For children EFSA suggests that ‘dietary fibre intake of 2 g per MJ should be adequate for normal laxation in children, based on the dietary fibre intake that is considered adequate for normal laxation in adults (25 g, equivalent to 2 to 3 g per MJ for daily energy intakes of 8 to 12 MJ) and taking into account that energy intake relative to body size in children is higher than in adults’ (EFSA 2010a).

For most essential nutrients, current UK requirements for children have been estimated by extrapolating published data for infants and adults, as little specific information for school-aged children existed when the DRVs were developed (DH 1991). During adolescence, most DRVs are set higher for boys than for girls because of their increased rates of growth, bone synthesis and bone mineralisation but the DRV for iron intake in post-pubertal girls is higher than for boys, to take account of blood lost during menstruation. However, discrepancies between iron intake data and iron status data (see section ‘Findings of the National Diet and Nutrition Survey’) have led to discussions around whether the iron intake recommendations may be set higher than necessary; some experts have suggested reassessing the DRVs for iron when more, good-quality dose–response data becomes available (SACN 2010).

High sodium intake in children, as well as in adults, has been associated with increased risk of high blood pressure and, in 2003, SACN established target average salt intakes for adults and children (Table 4), which are upper intake levels (SACN 2003). See sections ‘Findings of the National Diet and Nutrition Survey’ and ‘Food provision in school’ for details on salt intakes in schoolchildren.

Table 4. Target average salt intake in children aged 4–18 years
Age (years)Salt (g/day)Sodium equivalents (g/day)
Source: SACN 2003.
4–631.2
7–1052
11–1462.4
15+62.4

Vitamin D supplements (in the form of vitamin drops also containing vitamins A and C) are recommended for children under the age of 5 years. For schoolchildren, there are currently no recommendations for dietary vitamin D intakes as it has been expected that most people, with the exception of very young children, pregnant and breastfeeding women, and elderly people, obtain an adequate amount of the vitamin via the action of sunlight on the skin. However, it has become apparent that a substantial proportion of children (and adults) have low vitamin D status (see sections ‘Findings of the National Diet and Nutrition Survey’ and ‘Bone health’) and vitamin D recommendations are currently being reviewed by a SACN working group (www.sacn.gov.uk).

Various factors affect an individual's ability to produce vitamin D, including latitude, pigmentation of skin and style of dress. Solar ultraviolet (UV) radiation, which is required for the production of vitamin D in the skin, varies with latitude and time of year. From mid-October to the beginning of April, UV radiation in the UK is not strong enough to stimulate vitamin D synthesis, which means the body has to rely on dietary vitamin D and body stores. This situation is exacerbated in people with darker skin (as discussed later) and in general leads to lower blood vitamin D levels during winter and early spring (lowest in January to March) compared with summer and early autumn (highest in July to September). As a result, prevalence of low vitamin D status is generally higher during January to March (SACN 2007). Darker skinned people living in the UK, in particular those who have limited sun exposure because of their lifestyle or style of dress, may not achieve an adequate vitamin D status. Findings from a recent study suggest that children from ethnic minorities living in England also have lower dietary vitamin D intakes, further aggravating the situation. In particular, South Asian children had significantly lower vitamin D intakes compared with White European children, and intakes of Black African-Caribbean children were also lower (Donin et al. 2010). For more than two decades, the Department of Health has recommended that Asian children continue taking vitamin D supplements (10 μg/d) after the age of 5 years, particularly where religion and customs dictate that their skin is kept covered when outside, resulting in limited exposure of their darker skin to the relatively weak sunlight available in the UK (DH 1991), but communication of this message seems to have been limited and is now being reemphasised (along with advice about supplementation for other vulnerable groups).

Fluid requirements

Fluid requirements are an often overlooked aspect of diet. If lost fluid is not replaced, dehydration will result. In the short term, poor hydration causes headaches and constipation, and can cause irritability and impaired mental performance, which is particularly relevant for schoolchildren. In the longer term, chronic mild dehydration is associated with increased risk of a number of conditions, including urinary tract infections (see Benelam & Wyness 2010).

It is generally accepted that 6–8 glasses of fluid per day, appropriate for the size and age of the child, should be sufficient to replace water losses. Younger children need relatively smaller servings (e.g. 150 ml) than older children (e.g. 250–300 ml) (see Gibson-Moore 2013). These amounts are based on EFSA's DRVs for fluid, which are recommendations for adequate intakes under conditions of moderate environmental temperature and moderate physical activity levels (see Table 5). Children are, however, less heat tolerant than adults and can become dehydrated more quickly when exercising, particularly in hot weather. Therefore, more fluid will be needed in hot weather and after vigorous physical activity (Benelam & Wyness 2010). In adults, thirst is a good indicator of fluid needs, if responded to promptly. However, children may need to be encouraged to drink sufficient quantities to rehydrate, e.g. after exercise. There is some evidence that patterns of drinking are established in childhood and so it is important that children become used to maintaining an adequate fluid intake.

Table 5. The European Food Safety Authority's (EFSA's) recommendations for fluid intake for children
SexAge group (years)Amount of fluid from drinks and food (l/day)*Amount of fluid from drinks only (l/day)a
  1. Note: These values include water from both food and drinks (amounts from drinks only have been estimated). Adolescents of 14 years and older are considered as adults with respect to adequate water intake and therefore the adult values apply.

  2. *It is estimated that 70–80% of the recommended amount of fluid comes from drinks and 20–30% from food.

  3. a

    Estimated amount of fluid from beverages only.

Source: EFSA 2010b.
Boys and girls2–31.30.9–1.0
Boys and girls4–81.61.1–1.3
Girls9–131.91.3–1.5
Boys9–132.11.5–1.7
Girls14–182.01.4–1.6
Boys14–182.51.8–2.0

The importance of adequate hydration has been recognised and access to water has been included as a requirement in the various school food standards in the UK (see section ‘Food provision in school’). The British Nutrition Foundation has recently developed a guide for healthy hydration in children aged 4–13 years, suggesting that children drink plenty of water to keep hydrated, and that other drinks such as milk, juices and soft drinks can contribute to total fluid intake. However, when choosing drinks it is important to consider their nutrient value, calorie content, impact on dental health and caffeine content (Gibson-Moore 2013). For more information on healthy hydration in children, see www.nutrition.org.uk/healthyliving/hydration/hydration-for-children.

Findings of the National Diet and Nutrition Surveys (NDNS)

  1. Top of page
  2. Summary
  3. Introduction
  4. Nutritional requirements of schoolchildren
  5. Findings of the National Diet and Nutrition Surveys (NDNS)
  6. Nutrition and health in childhood
  7. Food provision in school
  8. Food in the curriculum
  9. Selected initiatives and organisations of relevance to child nutrition
  10. Acknowledgement
  11. Conflict of interest
  12. References

The NDNS provide comprehensive data on eating patterns of people aged 1.5 years and older living in private households in the UK. Data specifically on children (presented in four age groups) are available from an NDNS carried out in 1997 (Gregory et al. 2000), in which the eating patterns and nutrient intakes of over 1700 schoolchildren and adolescents (aged 4–18 years) in Britain were assessed. More recent data are also available for the first three years (2008–2011) of the NDNS Rolling Programme (Bates et al. 2012); data on more than 1300 children (aged 4–10 and 11–18 years) are available so far. In the NDNS Rolling Programme, data are collected over 4 rather than 7 days. To enable comparison of data from 1997 with data from 2008–2011, the data from 1997 were re-analysed by the researchers carrying out the NDNS Rolling Programme (for more detail, see Bates et al. 2010, 2011, 2012). The data currently available (for two age groups) provide a useful insight into energy and nutrient intakes in young people and how these have changed over the past decade.

Energy intake

The mean energy intakes reported in boys in 2008–2011 were lower compared with 1997 whereas, in girls, reported energy intakes remained fairly stable over the decade (see Table 6).

Table 6. Average reported daily energy intakes MJ (kcal) in boys and girls aged 4–18 years, in 1997 and 2008–2011
 1997 NDNS young people2008–2011 NDNS rolling programme Years 1, 2 and 3
  1. NDNS, National Diet and Nutrition Surveys.

Source: Gregory et al. 2000; Bates et al. 2012.
 MJ (kcal) per dayMJ (kcal) per day
Boys  
4–10 years7.08 (1680)6.68 (1586)
11–18 years8.95 (2130)8.28 (1965)
Girls  
4–10 years6.34 (1510)6.41 (1522)
11–18 years6.98 (1660)6.76 (1607)

Direct comparison of the new NDNS data with current EARs for energy is not possible as specific EARs are provided for each year of age rather than for the broader age categories used in the NDNS. However, average energy intakes of 11–18 year-olds were below the EAR for the lowest age within this category (i.e. 11 years), suggesting that average intakes in this age category do not exceed recommendations. In the light of high rates of overweight and obesity and low levels of activity, especially in older children, it is unlikely that energy intakes are generally below requirements (especially for children who are of normal weight or overweight). Underreporting of food and drink intake is also likely to be a factor and may also explain, at least in part, the apparent differences between the two time periods.

Macronutrient intakes

Intakes of macronutrients in the 1997 NDNS Young People Survey and in the first three years of the NDNS Rolling Programme are compared in Table 7. Figure 2 highlights that whereas total fat intakes are just below the recommended upper limit, intakes of saturated fatty acids and sugars are higher than recommended.

figure

Figure 2. Recommended upper intake levels for total fat, saturated fatty acids and non-milk extrinsic sugars, compared with average intakes of boys and girls aged 4–18 years in 2008–2011.

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Table 7. Average reported daily macronutrient intake and contribution to food energy intake in boys and girls aged 4–18 years, in 1997 and 2008–2011
 1997 NDNS young people2008–2011 NDNS Rolling Programme Years 1, 2 and 3
BoysGirlsBoysGirls
  1. NDNS, National Diet and Nutrition Surveys; NMES, non-milk extrinsic sugars; NSP, non-starch polysaccharides.

Source: Gregory et al. 2000; Bates et al. 2012.
Age (years)4–1011–184–1011–184–1011–184–1011–18
Protein, g/day (%E)53.0 (12.6)70.5 (13.5)48.4 (12.9)54.6 (13.4)57.4 (14.6)73.4 (15.2)54.1 (14.3)57.5 (14.8)
Total fat, g/day (%E)66.6 (35.4)83.6 (35.6)60.3 (35.9)66.0 (36.0)58.8 (33.3)74.1 (34.1)58.0 (34.0)61.4 (34.4)
Saturated fatty acids, g/day (%E)27.3 (14.5)32.7 (13.9)24.9 (14.8)25.6 (13.9)23.3 (13.1)27.7 (12.7)23.0 (13.5)22.4 (12.5)
Cis n-3 and n-6 Polyunsaturated fatty acids, g/day (%E)10.6 (5.6)14.4 (6.2)9.5 (5.7)11.8 (6.5)9.1 (5.2)12.0 (5.6)9.0 (5.2)10.3 (5.8)
Total carbohydrate, g/day (%E)233 (52.0)286 (51.0)206 (51.2)222 (50.8)220 (52.2)262 (50.6)209 (51.7)215 (50.9)
Total sugars, g/day (%E)109.8 (24.5)125.8 (22.1)98.6 (24.4)97.1 (21.9)99.4 (23.4)113.4 (21.7)96.9 (23.7)92.5 (21.7)
NMES, g/day (%E)77.4 (17.2)93.7 (16.4)69.2 (17.0)70.3 (15.8)61.7 (14.4)81.8 (15.6)60.8 (14.7)65.2 (15.0)
NSP fibre, g/day9.812.59.010.411.712.810.810.8

Table 8 reports the main contributors to energy and macronutrient intake, based on data from Years 1 and 2 of the NDNS Rolling Programme (Bates et al. 2011) because this type of information is not yet available for Years 1, 2 and 3 combined. However, it is not expected that the results combining all three years will differ significantly from those of Years 1 and 2.

Table 8. Contribution of food groups to energy and nutrient intakes in children and adolescents aged 4–18 years (2008–2010 NDNS Rolling Programme Years 1 and 2)
NutrientFood groupContribution to intake (% of total)
4–10 years11–18 years
  1. *NDNS groups foods together and the dominant contributor in the group will have been confectionery.

  2. NDNS, National Diet and Nutrition Surveys.

  3. Figures in italics signify a subset of the category (e.g. bread, a subset of cereal/cereal products).

Source: Bates et al. 2011.
EnergyCereals and cereal products3634
Meat and meat products1317
Milk and milk products159
Vegetables and potatoes1011
Non-alcoholic beverages (excluding milk)57
Sugar, preserves and confectionery66
Savoury snacks34
ProteinMeat and meat products2938
Cereals and cereal products2827
Milk and milk products2114
Fish and fish dishes54
Carbohydrate, totalCereals and cereal products4744
of which bread1716
of which breakfast cereals106
Vegetables and potatoes1112
Non-alcoholic beverages (excluding milk)914
Sugars, preserves and confectionery77
Milk and milk products96
NMESNon-alcoholic beverages (excluding milk)3040
of which soft drinks1629
of which fruit juice1310
Cereals and cereal products2922
Sugar, preserves and confectionery2221
Milk and milk products117
NSPCereals and cereal products4341
of which pasta, rice and other cereals911
of which white bread810
of which wholemeal, brown, granary and wheatgerm bread107
of which wholegrain and high fibre breakfast cereals75
Vegetables and potatoes2729
of which vegetables (excluding potatoes)1614
of which potatoes1215
Fruit117
Fat, totalMeat and meat products1924
Cereals and cereal products2423
Milk and milk products2013
Fat spreads108
Chips, fried potatoes and potato products68
Sugar, preserves and confectionery*56
Saturated fatty acidsMilk and milk products3122
Cereals and cereal products2424
Meat and meat products1723
Fat spreads98
Sugar, preserves and confectionery67
Protein

In 2008–2011 (NDNS Rolling Programme), protein intakes were higher than in 1997 for each age group in both boys and girls (Table 7). Even though direct comparison with RNIs is not possible because of the limited age categorisation in the data available currently from the NDNS Rolling Programme, findings from the earlier 1997 survey (where data for more age groups are available) show that protein intakes were well above the RNI in girls and boys of all age groups (see earlier section for protein RNIs). The main sources of protein in the diets of UK children are in Table 8.

Carbohydrate

The contribution of total carbohydrate to food energy in young people in 2008–2011 was similar to that in 1997 (Table 7), and was in both age groups close to the DRV of 50% of food energy (see earlier). The main sources of carbohydrate in the diet of UK children are presented in Table 8.

In the NDNS reports, sugars intake is reported as non-milk extrinsic sugars (NMES), and intrinsic sugars and milk sugars. NMES are sugars that are not contained within the cellular structure of food, whether natural, unprocessed or refined. NMES are typically present in table sugar, honey, fruit juice and all foods to which sugar has been added (e.g. cakes, biscuits, drinks and confectionery). In 2008–2011, NMES contributed on average 14.6% of food energy in 4–10 year-olds and 15.3% in 11–18 year-olds (Table 7). In 1997, the respective values were 17.1% and 16.0%, which means that there has been a clear decrease in the contribution of NMES to energy intake in 4–10 year-olds, and a small decrease in the 11–18 year-olds. However, NMES intakes still remain above the recommended upper level of intake (see Fig. 2). The main sources of NMES in the diets of schoolchildren are presented in Table 8. The largest contributors to NMES intake in schoolchildren are sugar-sweetened beverages and fruit juice, providing 40% of total NMES in 11–18 year-olds and 30% in the younger age group. In particular, the contribution from sugar-sweetened beverages increases with age (Bates et al. 2011).

Between 1997 and 2008–2011, intake of NSP increased by around 20% in both boys and girls in the younger age group, but little change was observed in boys and girls aged 11–18 years (Table 7). The main contributors to NSP in the diets of young people are shown in Table 8. A specific DRV for NSP does not exist for children (DH 1991) but EFSA has recommended 2 g/MJ for normal laxation (EFSA 2010a).

Fat

The average contribution of fat to energy intake in young children and adolescents decreased slightly between 1997 and 2008–2011 (Table 7). Findings from earlier reports showed that there had also been a decrease in average fat contribution to energy intake between 1983 and 1997 (see Buttriss 2002a). The older data (1997 vs. 1983) showed that fat had been replaced by sugar, whereas the change from 1997 to 2008–2011 is suggestive of a higher proportion of food energy now coming from protein. The most recent data show that average intakes of fat are now below the recommended population average intake of 35% food energy in both age groups (see Fig. 2). The main contributors to total fat intake are shown in Table 8.

Saturated fatty acid intake decreased between 1997 and 2008–2011 in both age groups (see Table 7). The average percentage of food energy from saturated fatty acids fell with age for both sexes, but intakes remained above the recommended upper level of 11% of food energy in both age groups in 2008–2011 (Fig. 2). The main contributors to saturated fatty acid intake are shown in Table 8.

The average intake of cis n-3 and n-6 polyunsaturated fatty acids (PUFA) combined has decreased in both boys and girls (both age groups) over the past 10 years (Table 7). Average intakes are below the combined DRV for cis n-3 and n-6 PUFA intake of 6.5% of food energy. The decrease in intake in both boys and girls was mainly due to decreases in n-6 PUFA intake, whereas n-3 PUFA intake as a proportion of energy intake has stayed at the same level. The 2012 NDNS report does not provide data on the main dietary contributors to PUFA intake. In the 1997 NDNS (Gregory et al. 2000), the major contributors to n-3 PUFA intake were: the category comprising vegetables, potatoes and savoury snacks (mainly from roast and fried potatoes, and chips), providing 34% in boys and 38% in girls; cereals/cereal products (18% and 16% respectively); and meat/meat products (17% and 16% respectively). Fish and fish dishes, mainly coated and fried white fish, contributed 5% of cis n-3 fatty acids in boys and 6% in girls. The main contributors to n-6 PUFA intake in 1997 were: the category comprising vegetables, potatoes and savoury snacks (providing 27% in boys and 29% in girls); cereals/cereal products (23% and 21% in boys and girls respectively); meat/meat products (18% and 16% respectively); and fat spreads (16% in boys and girls) (Gregory et al. 2000).

Micronutrient intakes

Table 9 shows the average daily intakes of vitamins and minerals in 2008–2011 compared with 1997 for boys and girls of different ages, expressed as average intakes, and Table 10 shows the proportion of children having intakes below the LRNI (see ‘Nutritional requirements of schoolchildren’ for the definition of LRNI).

Table 9. Average reported daily intake of vitamins and minerals from food sources and in boys and girls aged 4–18 years, in 1997 and 2008–2010*
 1997 NDNS young people2008–2010 NDNS Rolling Programme, Years 1 and 2
BoysGirlsBoysGirls
  1. *This information was not available from the 2012 NDNS report that covered the period 2008–2011.

  2. N/A, data not available; NDNS, National Diet and Nutrition Surveys.

Source: Bates et al. 2011.
Age (years)4–1011–184–1011–184–1011–184–1011–18
Vitamins:        
Vitamin A (retinol equivalent), μg485594470524675736666625
Retinol, μg274336261277282306258266
Thiamin, mg1.361.841.221.411.331.601.261.25
Riboflavin, mg1.611.851.391.341.581.581.421.25
Niacin equivalents, mg24.733.522.225.427.736.926.330.1
Vitamin B6, mg1.82.51.61.91.82.41.82.1
Vitamin B12, μg4.04.83.53.44.24.53.83.6
Folate, μg204276181210209239189192
Vitamin C, mg72.082.071.673.886.989.786.579.0
Vitamin D, μg2.32.92.02.21.92.41.91.9
Minerals:        
Iron, mg9.111.68.08.89.110.88.48.6
Calcium, mg739843659662838869767696
Magnesium, mg186239169189201230185187
Potassium, mg20702620192021502222255820832120
Zinc, mg5.98.05.46.16.78.46.36.6
Copper, mg0.770.990.690.800.811.040.790.86
Selenium, μgN/AN/AN/AN/A34443235
Iodine, μg154171135134153138133110
Table 10. Proportion of boys and girls aged 4–18 years with vitamin and mineral intakes below the lower reference nutrient intake (LRNI) in 1997 and 2008–2011
 1997 NDNS young people2008–2011 NDNS Rolling Programme Years 1, 2 and 3
Boys, %Girls, %Boys, %Girls, %
  1. NDNS, National Diet and Nutrition Surveys.

Source: Bates et al. 2010, 2012.
Age (years)4–1011–184–1011–184–1011–184–1011–18
Vitamins:        
Vitamin A (retinol equivalent)12141219612514
Thiamin00000000
Riboflavin1812218121
Niacin equivalents00000000
Vitamin B600000000
Vitamin B1201030102
Folate01150207
Vitamin C00000101
Minerals:        
Iron1534716146
Calcium21332307218
Magnesium324351028351
Potassium013131017031
Zinc11151926511819
Selenium022145
Iodine4531428321

By definition, if no more than 2.5% of a population have intakes below the LRNI then the likelihood of deficiency in the group is low, but Table 10 and Figure 3 demonstrate that significant proportions of young people have low intakes of a number of nutrients and that the situation is worse in the older age group. Using an arbitrary cut-off of 5%, low intakes of all reported minerals, vitamin A and riboflavin in boys and girls in the older age group, and also of folate in girls in the older age group, were evident. The prevalence of low intakes of iodine (below the LRNI) in older girls has increased over the past decade and there is also recent evidence from other studies of a high prevalence of mild to moderate iodine deficiency in a high proportion of British schoolgirls (Vanderpump et al. 2011). Iodine status measurements are now being recorded in the NDNS and a SACN scoping paper on iodine and health is expected shortly. In the younger age group, low intakes of vitamin A and zinc were evident in boys and girls (Bates et al. 2012).

figure

Figure 3. Proportion of 4–18 year-olds with intakes of selected micronutrients below the lower reference nutrient intake (LRNI), 2008–2011.

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There is as yet no information available from the new NDNS Rolling Programme on the main sources of vitamins and minerals in the diet. However, such information was available in the 1997 report and is presented in Table 11 for those nutrients identified as being of potential concern in the 1997 and 2008–2011 datasets.

Table 11. Food sources of the micronutrients that may be present in insufficient amounts in the diets of some young people
Nutrients for which low intakes are evidentMain sources in the 1997 National Diet and Nutrition Survey of young people aged 4–18 years, with contribution (%) provided in brackets
Source: Gregory et al. 2000.
Vitamin A (retinol equivalent)Vegetables (excluding potatoes) (∼27%); milk and milk products (∼20%); meat and meat products (∼15%, half of which came from liver); fat spreads (∼13%); cereal and cereal products (∼13%)
RiboflavinMilk and milk products (∼35%); cereal and cereal products (∼32%); meat and meat products (∼11%)
FolateCereal and cereal products (∼40%); vegetables, potatoes and savoury snacks (∼26%); milk and milk products (∼12%)
ZincMeat and meat products (∼31%); cereal and cereal products (∼25%); milk and milk products (∼20%); vegetables, potatoes and savoury snacks (∼12%)
IronCereal and cereal products, particularly breakfast cereals and bread (∼53%); vegetables, potatoes and savoury snacks (∼17%); meat and meat products (∼14%)
MagnesiumCereal and cereal products (∼31%); vegetables, potatoes and savoury snacks (∼22%) over half of which came from potatoes; milk and milk products (∼16%); meat and meat products (∼11%)
CalciumMilk and milk products (∼48%); cereal and cereal products, particularly bread (∼27%)
PotassiumVegetables, potatoes and savoury snacks (∼34%), with two-thirds coming from potatoes; milk and milk products (∼17%); cereals and cereal products (∼15%); meat and meat products (∼13%)
IodineMilk and milk products (∼50%); cereal and cereal products (∼16%); fish and fish dishes (∼8%)

Some of the main contributors to intakes of essential vitamins and minerals are also major contributors to nutrients that most children should consume less of, such as saturated fatty acids and NMES. For example, meat/meat products and dairy products are major contributors of essential nutrients such as iron, zinc, calcium, riboflavin and vitamin B12, but also contribute to energy, total fat, saturated fatty acids and salt intakes. This paradox highlights an important issue – that when recommending or choosing foods it is often not helpful to focus on isolated nutrients or single messages, particularly as diets are complex and dietary patterns that are deficient in one aspect are often requiring improvement on a number of fronts. For example, advising adolescent girls to eat less meat in order to reduce intake of saturated fat may lead to a further erosion of already low intakes of iron and zinc in this age group. Another point worth noting is that, given the concentration of essential micronutrients in milk, regular inclusion of reduced fat milk and dairy products could increase intakes of the majority of the nutrients illustrated in Figure 3 (that are currently present in inadequate amounts in the diets of some teenage girls), in particular iodine, riboflavin, vitamin A, zinc, potassium and magnesium, as well as calcium.

A recent publication presenting standardised data on vitamin and mineral intakes in eight European countries (Belgium, Denmark, France, Germany, The Netherlands, Poland, Spain and the UK) showed that low intake levels (below the LRNI) of several micronutrients are found in children aged 11–17 years throughout Europe (Mensink et al. 2013). As in the UK, this is far less of an issue in children aged 4–10 years. Nutrients where more than 5% of children age 11–17 years had intakes below the LRNI included calcium, iron, magnesium, potassium, selenium and vitamin A, illustrating that poor micronutrient intakes in sections of the population is not exclusively a UK problem.

Salt

Measuring sodium intake is more complex than measuring the intake of other nutrients, as it is often difficult to establish how much salt (the main source of sodium in the diet) is added to food during preparation (and the extent to which salt is present in the food when consumed as it may remain in the cooking water) and at the table. Therefore, urinary sodium excretion is the most reliable method to measure salt intake; but currently no data on sodium intake in children from urinary sodium excretion studies are available from the NDNS. Data are expected to be published in 2014. However, a study commissioned by the Public Health Research Consortium, England, which evaluated the impact of change in school food policy on food and nutrient intake of children aged 4–7 and 11–12 years, provides some data on sodium intake assessed by means of a dietary intake questionnaire. The findings suggested sodium intakes of 1.85 g/day (4.6 g salt) in 4–7 year-olds and 2.15 g/day (5.4 g salt) in 11–12 year-olds. Intake levels in the younger age group are clearly above the recommended upper level for 4–6 year-olds of 1.2 g sodium (3 g salt) per day, whereas intakes of 11–12 year-olds were below the recommended upper level of 6 g per day (Adamson et al. 2011). It should be noted that it is possible that sodium intake levels were underestimated by relying solely on a dietary questionnaire.

Micronutrient status

The 2012 NDNS report provides information on nutritional status, derived from analysis of blood samples taken from boys and girls aged 11–18 years (data for the younger age group has yet to be published) (Table 12) (Bates et al. 2012). Nutritional status relates to the level of nutrients available to the body (after absorption) for use in metabolic processes. For some micronutrients, status can be assessed directly by measuring the level of the nutrient in the blood, while for others it is assessed by a functional measure or biochemical marker indicative of status.

Table 12. Vitamin and mineral status in boys and girls aged 11–18 years, in 2008–2011
AnalytesIndicative ofBoys, 11–18 years, %Girls, 11–18 years, %
  1. EGRAC, erythrocyte glutathione reductase activation coefficient.

Source: Bates et al. 2012.
Plasma ferritin <15 μg/lLow iron levels (long-term)7.630.2
Haemoglobin <age-specific thresholdLow iron levels (short-term)1.18.8
Plasma vitamin C <11 μmol/lBiochemical vitamin C depletion0.30
Serum vitamin B12 <150 pmol/lLow vitamin B12 levels1.94.2
EGRAC >1.30Low riboflavin levels73.789.2
Plasma 25-hydroxyvitamin D <25 nmol/lInadequate vitamin D status19.320.4

Three-quarters of boys and almost 90% of girls aged 11–18 years had levels of a biochemical marker considered to be indicative of inadequate riboflavin status, reflecting the low intakes in this age group (but it should be noted that a recent review of the biomarker methodology for riboflavin by SACN suggests that the threshold values may need revision; hence the problem may not be as severe as the data suggests). See Table 11 above for dietary sources of riboflavin. Vitamin D status is also of concern, with around 20% of 11–18 year-olds showing evidence of low status (see section ‘Bone development’ for further details).

Almost a third of girls aged 11–18 years had low serum ferritin levels, reflecting low long-term intakes of iron in this population group compared with requirements; fewer boys (8%) were affected. Low haemoglobin levels, indicative of iron deficiency (anaemia) and reflecting short-term intakes of iron, were found in almost 9% of girls and 1% of boys aged 11–18 years.

Blood folate levels (a measure of folate status) have not been reported in the latest NDNS report, but will be published in due course. Folate status in adolescent girls/young women is of particular interest because of the association between low folate status during pregnancy and risk of neural tube defects in the fetus.

Fruit and vegetable intake

Intakes of fruit and vegetables combined (including from composite dishes, but not including juice or potatoes) were higher in 4–10 year-olds (207 g/day) than in 11–18 year-olds (177 g/day). This was mainly due to a higher intake of fruit in the younger compared with the older age group (107 vs. 62 g/day), although vegetable intake was lower in 4–10 year-olds compared with the older age group (100 vs. 115 g/day). Only 9% of 11–18 year-olds achieved the recommended five portions a day (Bates et al. 2012). Comparable information is not provided in the report for younger children because there is limited information on what constitutes a portion of fruit or vegetables for young children. Fruit and vegetables from composite dishes were not considered in previous reports, which is why the intakes mentioned earlier are not directly comparable with previous data. However, data on fruit and vegetable intakes excluding contribution from composite dishes can be compared (although overall amounts would be lower than if contribution of composite dishes was considered). Using this approach, average intake of vegetables (excluding potatoes) increased from 63 g/day to 77 g/day and fruit intake increased from 66 g/day to 101 g/day in 4–10 year-old children between 1997 and 2008–2011. In those aged 11–18 years, fruit intake increased to a lesser degree from 49 g/day to 58 g/day, whereas vegetable intake decreased from 85 g/day to 78 g/day. A likely explanation of the improvements in the younger, but not the older, age group is that the diets of younger children can more easily be controlled by parents (who may be increasingly aware of the benefits of providing fruit and vegetables) and in school, through the implementation of school food standards as well as via free school fruit schemes (see section ‘Food provision in school’ for more details).

Dietary supplements

During the 4-day recording period, supplements were taken by 17% of 4–10 year-olds and 7% of 11–18 year-olds, including fish oil, plant oil, vitamin and/or mineral supplements (Bates et al. 2012). Twenty-eight per cent of 4–10 year-olds and 23% of 11–18 year-olds were reported to have consumed supplements in the year prior to the interview taking place. The most common types of supplements consumed were fish oil, and multivitamins with or without minerals. When considering the additional contribution of supplements to nutrient intakes, the proportions of subjects with intakes below the LRNI hardly changed, suggesting that those who take supplements already have a healthier diet overall (Bates et al. 2012).

Vegetarians and vegans

In the 2012 NDNS report, 1% of 4–10 year-olds and 2% of 11–18 year-olds were reported to be following a vegetarian (or vegan) diet. No sex-specific data are available at this stage, but data from the 1997 report showed that more girls than boys were vegetarian or vegan, and the proportion following this type of diet increased with increasing age. Vegetarians tended to come from non-manual family backgrounds. About two-thirds said they avoided meat for moral or ethical reasons and about a third said they did not like the taste of meat. Interestingly, parental or religious reasons were given far less often. Plasma iron and haemoglobin levels were significantly lower in vegetarians compared with omnivores. However, there was no difference in vitamin B12 status, despite the fact that this vitamin is only available naturally via foods of animal origin (principally milk and meat), although it is added to a number of fortified foods (e.g. breakfast cereals and soya products). In 1997, low-density lipoprotein (LDL) cholesterol levels were lower and the biochemical status of several vitamins and of selenium was higher among the group consuming a vegetarian diet (Gregory et al. 2000). This type of information is not available from the 2012 NDNS report (Bates et al. 2012).

Regional and socio-economic differences

Data on regional and socio-economic differences in food and nutrient intake are available from the 1997 NDNS and from the Low Income Diet and Nutrition Survey (LIDNS), and were presented in detail in the 2011 Briefing Paper ‘Nutrition, health and schoolchildren (see Weichselbaum & Buttriss 2011). Comparable data for the NDNS Rolling Programme are not yet published.

Types of foods eaten

Both the 1997 NDNS and LIDNS revealed differences in food intake between households of different income levels. Children from households with lower incomes tended to consume less skimmed or semi-skimmed milk, wholemeal bread, and fruit and vegetables, and more whole milk, pizza, processed meats, meat-based dishes and non-diet soft drinks compared with children from households with higher incomes (see Box 1) (Gregory et al. 2000; Nelson et al. 2007). Data from the 2008 Health Survey for England shows that children's fruit and vegetable consumption varies with household income. Mean daily portions of fruit and vegetables consumed was higher in those in the highest two quintiles of income compared with the lowest three; there was no meaningful difference between the lowest three quintiles of income (see Fig. 4). Those in the highest income bracket were also most likely to meet the 5 A DAY target (27% of boys and 30% of girls), whereas no significant differences were found between the remaining four quintiles (16–20%; the proportion of those achieving five portions a day was only slightly higher in the second highest quintile compared with the three lowest quintiles). Only 2% of children in the highest quintile had eaten no fruit or vegetables in the 24-hours prior to their being interviewed, compared with 12% of boys and 7% of girls in the lowest quintile (Craig et al. 2009b).

figure

Figure 4. Mean daily portions of fruit and vegetables consumed by 5–15 year-olds living in England, 2008, by equivalised household income and sex.

*Equivalised household income is a measure that takes account of the number of people in the household. For this analysis, households were split into five equal-sized groups banded by income level (income quintiles). Fruit and vegetable portions consumed were compared among these groups.

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Box 1. : Differences in average food consumption over seven days between children in the LIDNS report (low-income families) compared with children in the 1997 NDNS report (general population)

Lower consumption by children in LIDNS compared with 1997 NDNS:

  • wholemeal bread (girls 24 vs. 42 g);
  • buns, cakes and pastries (boys 121 vs. 166 g, girls 98 vs. 135 g);
  • semi-skimmed milk (boys 634 vs. 798 g, girls 447 vs. 524 g);
  • skimmed milk (boys 9 vs. 33 g, girls 11 vs. 39 g);
  • vegetables (boys 318 vs. 346 g, girls 380 vs. 411 g);
  • fruit (boys 321 vs. 366 g);
  • fruit juice (boys 329 vs. 380 g);
  • carbonated soft drinks (diet) (boys 347 vs. 457 g, girls 339 vs. 453 g).

    Higher consumption by children in LIDNS compared with 1997 NDNS:

  • pizza (boys 163 vs. 112 g, girls 107 vs. 73 g);
  • whole milk (boys 873 vs. 632 g, girls 620 vs. 501 g);
  • fat spreads (boys 86 vs. 52 g, girls 71 vs. 43 g);
  • beef, veal, lamb and pork and dishes (boys 309 vs. 240 g, girls 282 vs. 199 g);
  • processed meats (boys 449 vs. 369 g, girls 385 vs. 280 g);
  • oily fish and canned tuna (boys 31 vs. 24 g, girls 31 vs. 28 g);
  • non-carbonated soft drinks (not diet) (boys 1652 g vs 913 g, girls 1342 vs. 755 g);
  • carbonated soft drinks (not diet) (boys 1693 vs. 1136 g, girls 1123 vs. 856 g).

Source: Gregory et al. 2000; Nelson et al. 2007.

Nutrient intake

Despite regional differences in the types of foods eaten in the 1997 NDNS, there were few significant differences in mean energy intake or protein, carbohydrate or alcohol intake. Overall, intakes of most vitamins and minerals tended to be lower in Scotland and to a lesser extent in the northern regions of England compared with other regions, in part reflecting the lower intakes of vegetables compared with London and the South East, where vitamin and mineral intakes were highest. Even after adjusting for energy intake, lower intakes of vitamin D, iron and manganese in boys, and folate and pantothenic acid in girls still remained in Scotland and in the North of England. Also, lower intakes of iron and manganese in girls and of zinc in both sexes were still present after adjustment for energy intake (Gregory et al. 2000).

In the 1997 NDNS, differences in nutrient intakes between regions were more marked when analysed against socio-economic status (SES), as indicated by receipt of benefits, household income and social class in the 1997 NDNS. Although, overall, there was no difference in total energy intake, there were differences among boys, energy intake being lower in those whose parents were in receipt of benefits (7.22 MJ compared with 8.27 MJ per day). In 1997, children from households in lower income groups and those from households in receipt of benefits were significantly more likely to have lower mean intakes of protein, total carbohydrate, NMES and NSP than those from other households (Gregory et al. 2000).

With regard to total fat intakes, no socio-economic differences were found in 1997 but, when expressed as a percentage of energy, it was found that the diets of boys (but not girls) from manual social classes contained more cis monounsaturated and PUFAs than those from non-manual backgrounds, which may reflect the type of spread used or vegetable oil (via fried foods) consumption.

Vitamin C intakes were significantly lower in both boys and girls from lower socio-economic backgrounds, even after adjusting for energy intake. Average intakes of all minerals, with the exception of iron, were significantly lower among boys (but not girls) in households in receipt of benefits. These differences in intakes persisted for calcium in boys and calcium, phosphorus and iodine in girls, even after adjusting for energy intake (Gregory et al. 2000).

Nutrient status

In 1997, blood levels of vitamin C and folate were lower in Scotland and Northern England than elsewhere; this is likely to be linked to intake of fruit and vegetables. Girls in London and the South East had higher iron stores than in any other region and girls from the Northern region of England had the lowest plasma vitamin C levels. Lower nutritional status was found in the lower socio-economic groups for folate, vitamin C, vitamin D and iron (Gregory et al. 2000). Comparable data from the NDNS Rolling Programme is not yet available.

Nutrition and health in childhood

  1. Top of page
  2. Summary
  3. Introduction
  4. Nutritional requirements of schoolchildren
  5. Findings of the National Diet and Nutrition Surveys (NDNS)
  6. Nutrition and health in childhood
  7. Food provision in school
  8. Food in the curriculum
  9. Selected initiatives and organisations of relevance to child nutrition
  10. Acknowledgement
  11. Conflict of interest
  12. References

Dietary patterns and health

Breakfast

Starting the day with breakfast is considered to be beneficial for various aspects of health, including nutritional status, cognitive function (for more details see section on ‘Cognitive function’) and bodyweight control. Breakfast consumption, in particular consumption of breakfast cereals (with milk), has been linked to higher micronutrient intakes (e.g. Gibson 2003; Williams 2007; Gibson & Gunn 2011; Holmes et al. 2012). In UK children, overall nutrient intakes of breakfast cereal consumers have been shown to be better than those of children not consuming cereals (which would include children eating another type of breakfast and also children skipping breakfast) (Gibson 2003; Holmes et al. 2012).

As well as providing B-vitamins and iron, some breakfast cereals are also fortified with calcium and vitamin D (Williamson 2010). In an analysis of data from the 1997 NDNS, Gibson found that children aged 4–18 years with the lowest consumption of breakfast cereals (lowest tertile of intake) had significantly lower intakes than other children of five B-vitamins (thiamin, riboflavin, niacin, B6 and folic acid), plus iron and vitamin D. Compared with intakes in the lowest tertile, those in the highest tertile of breakfast cereal consumption had iron intakes that were 42% (girls) and 33% (boys) higher. Intakes of B-vitamins and vitamin D were around 20–60% higher in those consuming breakfast cereals more frequently. Higher calcium intakes among moderate-to-high consumers of breakfast cereals are likely to be attributable to a higher consumption of milk, which will also have contributed to the differences in riboflavin and zinc intakes. Children who consumed least cereal were between two and eight times more likely to have vitamin and mineral intakes below the LRNI, compared with those who ate most. For example, 42% of girls in the lowest tertile of cereal intake had iron intakes below the LRNI, compared with 11% of girls in the highest tertile. Comparable figures for calcium were 22% vs. 9%, and for riboflavin 25% vs. 3%. These differences were statistically significant (Gibson 2003).

In another study, the contribution of breakfast cereals to micronutrient intakes in the materially deprived population was assessed using data from the LIDNS (Holmes et al. 2012). Children aged 2–18 years who consumed breakfast cereals had higher intakes of thiamin, riboflavin, niacin, biotin, folate, vitamin B6, vitamin B12 and iron than non-consumers. The proportion of children meeting the UK RNIs for these micronutrients was also consistently higher in those who regularly consumed breakfast cereals (Holmes et al. 2012).

An extensive systematic review by Summerbell et al. (2009) looked at evidence from two prospective cohort studies to establish whether a relationship existed between eating/skipping breakfast in childhood and weight gain. The authors concluded that there was no epidemiological evidence of a consistent association between breakfast skipping and subsequent excess weight gain or obesity. However, limitations of the studies included self-reported overweight and obesity in one of the studies, whereas the other study was small and did not adjust for physical activity levels. The larger of the studies had a one-year follow-up period, which may have been insufficient to observe any significant changes in bodyweight (Summerbell et al. 2009). Another systematic review included both cross-sectional and cohort studies. The authors found that 13 out of the 16 included studies (the majority being cross-sectional) consistently showed a protective effect of eating breakfast against becoming overweight or obese; four studies that reported on the association between breakfast and body mass index (BMI) all found an increase in BMI in breakfast skippers (Szajewska & Ruszczynski 2010). However, the authors pointed out that as almost all of the information gathered in the systematic review was from observational studies, causality should not be assumed based on these findings, which means that factors other than having breakfast per se may be responsible for the observed association (e.g. an overall healthier lifestyle).

A more recent systematic review including 11 cross-sectional studies, two prospective studies and one intervention study looked specifically at the association between consumption of breakfast cereals and bodyweight (de la Hunty et al. 2013). The findings suggested that regular consumption of breakfast cereals was associated with a lower BMI and a reduced likelihood of being overweight in children and adolescents. Meta-analysis of results from cross-sectional studies resulted in a lower BMI (by 1.13 kg/m2) in high consumers of breakfast cereals compared with low/non-consumers. It should be noted that average daily energy intakes in high consumers of breakfast cereals were significantly higher in 12 out of 20 studies. This suggests that factors other than breakfast cereal consumption per se are likely to have contributed to the observed associations. For example, children who regularly consume breakfast cereals may be more physically active than those who consume breakfast cereals less frequently. There is also the possibility that a low consumption of breakfast cereals is a result of skipping breakfast in order to lose weight, which would mean the low consumption could be a result of the higher bodyweight rather than vice versa. No conclusions on causality can be drawn given the types of studies available for inclusion in the meta-analysis (de la Hunty et al. 2013).

Overall, eating breakfast regularly seems to be associated with lower bodyweight and lower risk of becoming overweight or obese. However, no conclusions on ‘cause and effect’ can be drawn and it is likely that factors other than breakfast per se, for example a healthier lifestyle overall, may contribute to the observed associations.

Meal frequency and snacking

Snacking can potentially make a useful contribution to the consumption of fibre and various micronutrients, depending on the types of snack consumed (Miller et al. 2013). Although snacks are often perceived as being less healthy, a study in UK children aged 11–12 years found no evidence to suggest the nutrient composition of snacks was any more or less healthy than that of foods consumed during meals, and the types of foods consumed as snacks did not differ from those consumed during mealtimes. Sodium density of snack foods and foods consumed at meal time also did not differ. In this study, snacks (defined as any foods eaten outside the three main eating events) were found to contribute at least 30% of the children's nutrient intakes (including protein, carbohydrate, fat, fibre, iron, calcium, thiamin, riboflavin, folate, carotene and vitamin C) (Adams et al. 2005). The definition of snacks used in this survey means that any food can count as a snack, provided it is eaten outside of main meals. Other definitions use different criteria, for example the food type or the energy content or nutrient profile of a food/snack, rather than the occasion at which the food is eaten (see Miller et al. 2013).

Snacking between meals is commonly believed to be contributing to the increased incidence of overweight and obesity within populations. However, the evidence linking snacking and bodyweight remains inconsistent, with some studies showing positive, some negative and some no associations between snacking and bodyweight (see Miller et al. 2013). A recent meta-analysis of mainly cross-sectional studies found that a higher eating frequency was in fact associated with a 22% reduction in risk of being overweight or obese, suggesting that eating more frequently is beneficial for bodyweight. However, the authors of the review highlighted several limitations of their analysis, for example that some studies did not adequately control for other diet and lifestyle factors that may have contributed to any observed association. For example, individuals who snack more frequently may do so in association with a more active lifestyle and, therefore, the potential increase in energy intake would be offset by, or in response to, greater energy expenditure. Positive associations between energy intake and snacking have been found in several studies but the same studies found an inverse correlation between snacking and bodyweight, which may at least be partly explained by the observed positive association between snacking and physical activity (see Miller et al. 2013). In addition, different definitions of ‘snacking’ and overweight/obesity were used. The association was statistically significant in boys but not in girls. The study authors noted this could be due to the sub-analysis in girls being underpowered. There was a risk of publication bias and significant heterogeneity between studies, and the authors suggested that further investigations in this field are warranted (Kaisari et al. 2013). Of note, most of the included studies were carried out in Mediterranean countries, and only two were in North American or Northern European populations (USA and Germany).

Portion size and energy density

It has been shown that presenting children with larger portions leads to an increased intake of the respective food, but also to an increased food and energy intake overall (see Benelam 2009). However, this effect was not found in very young children (3 years or younger), where increasing portion size does not seem to lead to an increased food intake (Fisher & Kral 2007; Benelam 2009). One study looked at the effect of increasing portion size as well as the energy density of an entrée presented to children aged 5–6 years on total food and energy intake during one meal occasion. In accordance with earlier findings, the authors found an increased food intake when children were presented with a larger portion size, but did not find any influence of energy density on the total amount of food consumed during the meal (Fisher et al. 2007). This suggests that children do not compensate for the higher energy density by eating a smaller portion, which in turn can lead to an overall higher energy intake if energy-dense foods are consumed regularly. Research so far does not suggest that the tendency to overeat when large portions are presented is specific to overweight children (Fisher & Kral 2007).

Sugar-sweetened beverages

The consumption of sugar-sweetened beverages (including carbonated drinks and fruit drinks) has increased alongside increases in obesity prevalence, particularly in the USA, leading to speculations that these drinks may be partly responsible for the obesity epidemic (Malik et al. 2006). However, the evidence on the effect of sugar-sweetened beverages on bodyweight and body fat is as yet inconclusive (see Benelam & Wyness 2010; Hauner et al. 2012) and wide variation in study designs, definitions of sugar-sweetened beverages and outcomes makes studies difficult to interpret collectively (Althuis & Weed 2013). A meta-analysis of evidence from prospective cohort and experimental studies in children and adolescents found no association between intake of sugar-sweetened beverages and BMI (Forshee et al. 2008). However, this study was criticised for the method used to weight the studies (Malik et al. 2009). Malik and colleagues repeated the meta-analysis addressing this issue and also excluded studies that adjusted for energy, as it was suggested that including these studies had resulted in an underestimation of the effect of sugar-sweetened beverages on bodyweight. This re-analysis led to a significant positive association between consumption of sugar-sweetened beverages and bodyweight (Malik et al. 2009). Another systematic review conducted a series of meta-analyses based on study design and outcome measure (Vartanian et al. 2007). The meta-analysis of data from longitudinal cohort studies (excluding experimental studies) also found a significant association between sugar-sweetened beverage consumption and bodyweight, but reported that the effect size was distinctly lower for children than for adults and was almost zero (Vartanian et al. 2007). In this study, effect size was also larger when weight was self-reported compared with when weight was measured, although the opposite could have been expected. Only two experimental studies in children were included in this review, meta-analysis of which resulted in a non-significant positive association. Larger effect sizes were observed in the experimental studies than in longitudinal (or cross-sectional) studies (Vartanian et al. 2007). A meta-analysis including only intervention studies (6 studies overall) did not show any significant effect of lowering the consumption of sugar-sweetened beverages on BMI. However, the authors of the review noted that the primary endpoint of these studies was to see whether an educational intervention could reduce sugar-sweetened beverage consumption, i.e. the studies were not designed to test whether reduction of sugar-sweetened beverage consumption per se would result in weight loss. In addition, interventions were not comparable and study duration was generally relatively short (Mattes et al. 2011).

The German Nutrition Society concluded in their evidence-based guidelines on carbohydrates that the evidence supporting a link between increased risk of obesity and higher consumption of sugar-sweetened beverages in children and adolescents can at best be judged as ‘possible’, highlighting conflicting findings of various studies and meta-analyses (Hauner et al. 2012). Its report suggests there is possible publication bias, with industry-funded studies being less likely to find an association, but also bias in the other direction with the public health sector expecting a risk-association, which could potentially lead to preferred publication of confirming studies (Hauner et al. 2012). In a recent systematic review, 15 out of 23 included cohort studies reported a positive association between sugar ‘exposure’ (14 of these studies reported sugar ‘exposure’ as consumption of sugar-sweetened beverages) and a measure of adiposity. When the review authors did a meta-analysis of findings from five prospective cohort studies, the findings suggested that children consuming one or more servings of sugar-sweetened beverages per day were 55% more likely to be overweight or obese (Te Morenga et al. 2012). The latest systematic review and meta-analysis, carried out by Malik and colleagues, found that based on 20 comparisons from 15 studies, one additional daily serving of sugar-sweetened beverages was associated with a significant increase in BMI of 0.07 kg/m2 (based on follow-up durations of 6 months to 14 years). When analysing the one-year change in BMI based on 11 comparisons from 7 studies, Malik and colleagues found that one additional serving of sugar-sweetened beverages was associated with a significant increase in BMI of 0.06 kg/m2. Meta-analysis of five intervention studies that each aimed to achieve weight loss by reducing sugar-sweetened beverage consumption did not result in a significant overall effect. However, when only considering the three intervention studies where sugar-sweetened beverages were replaced with diet beverages (as opposed to simply telling children to drink less sugar-sweetened beverages), a significant average weight reduction was achieved, although the overall effect was relatively small (−0.34 kg over a period of 24 weeks to 18 months). The authors also found that any association or effect was clearly smaller in children compared with adults (Malik et al. 2013).

Recently published findings of a prospective study in almost 700 American adolescents found that consumption of diet soft drinks was significantly associated with a higher BMI, even after adjusting for various confounding factors including physical activity, total energy intake, parental education and age (Laska et al. 2012). Consumption of sugar-sweetened beverages was not associated with a higher BMI. The authors suggested a reverse causality to be partly responsible for these findings, i.e. those who are already overweight or obese may be more likely to choose diet drinks. This highlights the complexities when trying to find an association between any dietary behaviour and bodyweight. Another interesting finding comes from the ENERGY (EuropeaN Energy balance Research to prevent excessive weight Gain among Youth) project, a pan-European, European Union (EU)-funded project. In the course of this project, a school-based survey was carried out among schoolchildren aged 10–12 years from seven European countries (Belgium, Greece, Hungary, The Netherlands, Norway, Slovenia and Spain). The country with the highest prevalence of overweight and obesity (Greece) had the lowest soft drink consumption, whereas the country with the highest consumption of soft drinks (Netherlands) had only the fourth highest prevalence of overweight and obesity, even though consumption of soft drinks was about five to six times as high as in Greece (Brug et al. 2012). Although no analyses were carried out to identify possible associations and such associations are purely cross-sectional, these findings highlight that obesity is the result of a variety of factors and not solely one single factor.

It has been suggested that energy-containing liquids could lead to excess energy consumption because they fail to trigger satiety compared with equivalent energy intakes from solid food and it has been proposed this may be due to their rapid transit through the stomach and intestines (Pan & Hu 2011). However, studies comparing the effects of equivalent amounts of liquid or solid energy on satiety have yielded inconsistent results and do not consistently support the hypothesis that liquid calories go undetected by appetite control systems (Drewnowski & Bellisle 2007; also see Bellisle et al. 2012). In particular, in intervention studies, meal replacement drinks (often high in sugar) have been shown to help with weight loss, suggesting that liquids can trigger satiety (Drewnowski & Bellisle 2007). Another limitation of evidence on the effect on satiety of energy-containing liquids is that many studies are only short-term (i.e. investigating the immediate satiety response rather than the effect of foods on long-term energy homoeostasis) (Pan & Hu 2011). Another important point to consider is that the amount we eat and drink is not only influenced by satiety but also by many other behavioural factors. Therefore, the association between consumption of caloric liquids and satiety may have less relevance for overall energy consumption than some may assume (Drewnowski & Bellisle 2007; Bellisle et al. 2012). Replacing sugar-sweetened foods and beverages with non- or low-calorie options is a way to reduce energy intake, but it has been argued that non-nutritive sweeteners may actually increase appetite and stimulate excessive energy intake because provision of sweetness without energy may confuse the body's regulatory mechanisms (Pan & Hu 2011). Others argue that this claim is not supported by recent evidence (Bellisle et al. 2012).

Overall, the evidence around sugar-sweetened beverages and overweight and obesity remains conflicting. Most of the evidence comes from observational studies, which means no ‘cause–effect’ relationships can be established, and it is possible that other factors that may have contributed to any associations (or lack of association) may have not been adequately considered. Many of these studies are also based on US cohorts where sugar-sweetened beverage consumption tends to be higher and formulations different. Although a number of reviews of the effects of sugar-sweetened beverages on health outcomes such as bodyweight have been published, these have been rated as moderately low using the validated AMSTAR tool (Weed et al. 2011). Less than one-third, for example, reported a comprehensive literature search, listed included and excluded studies, or used duplicate study selection and data abstraction. Therefore, based on current evidence, no conclusions on an association between sugar-sweetened beverages and overweight and obesity can be drawn.

Physical activity

The level of physical activity, its frequency, duration, intensity, type and total amount, as well as the time spent sedentary, have a major impact on health at all stages of life. There is concern that many children spend too much time undertaking sedentary activity (see ‘Sedentary behaviour’ at the end of this section). Physical inactivity has been identified as the fourth leading risk factor for global mortality (6% of deaths globally). This follows high blood pressure (13%), tobacco use (9%) and high blood glucose (6%). Overweight and obesity are responsible for 5% of global mortality (WHO 2010). Being physically active in early life is of particular importance as it affects not only current health status but can also influence health in later life. The many benefits for children and young people of being physically active include helping to maintain energy balance and therefore a healthy bodyweight; aiding bone and musculoskeletal development; reducing the risk of diabetes and hypertension; as well as numerous psychological and social benefits (including improved psychological wellbeing, and higher self-confidence and self-esteem) (see Miles 2007). This section focuses on physical activity recommendations, on how much physical activity children in the UK are actually doing and on the factors that influence physical activity levels.

Physical activity is defined as ‘any bodily movement produced by skeletal muscles that requires energy expenditure’ (WHO 2010). It therefore includes activities ranging from organised sport and exercise, to active play (running around outside) or activities undertaken as a part of everyday living (i.e. walking or cycling to school, housework). Physical activity can take a number of forms and types, such as moderate or vigorous intensity, or activities that convey particular benefits, e.g. aerobic or weight bearing activities that benefit the cardiovascular system and skeleton, respectively (see Miles 2007).

Recommendations in the UK

In 2011, for the first time, UK-wide physical activity recommendations were published; previously, each of the countries had separate recommendations regarding the amount and intensity of physical activity that should be undertaken. Recommendations on physical activity exist for all age groups. The recommendations for 5–18 year-olds are presented in Table 13. For the first time, the physical activity guidelines also include a recommendation to reduce the amount of time spent sitting.

Table 13. Current recommendations for physical activity in the UK
Children's physical activity recommendations
Source: Chief Medical Officers 2011.
  • All children and young people should engage in moderate to vigorous intensity physical activity for at least 60 minutes and up to several hours every day;
  • vigorous intensity activities, including those that strengthen the muscle and bone, should be incorporated at least three days a week;
  • all children and young people should minimise the amount of time spent being sedentary (sitting) for extended periods.

Moderate intensity activity can broadly be defined as that which raises the heart rate and leaves an individual slightly out of breath, but still able to talk. The recommended 60 minutes can be made up of smaller bursts of activity, which reflects the typical activity patterns of children [i.e. walking to school, spontaneous play, as well as structured activity such as Physical Education (PE) lessons]. Variety is important at this age: moderate to vigorous bouts of activity will benefit the cardio-respiratory system; activities to improve bone health are those which produce high physical stress on the bones, and include running, jumping and skipping; active play (e.g. climbing, carrying and ‘rough and tumble’) helps to improve muscle strength and flexibility.

For a summary on how physical activity levels are measured, see Weichselbaum and Buttriss (2011).

Current activity levels of children across the UK

Data on physical activity levels in children aged 7 years are now available for a UK-wide representative sample participating in the Millennium Cohort Study (Griffiths et al. 2013). Previously, the only data available were from regional surveys that employed different methodologies and so were generally not comparable. In the Millennium Cohort Study, physical activity levels, including time spent being sedentary, were assessed (in 2008/2009) using an accelerometer that had been previously demonstrated to measure physical activity levels reliably. The findings are presented in Table 14. Overall, only around half of 7-year-old children in the UK met the recommended 60 minutes of moderate to vigorous activity per day. There was a large difference between boys and girls, with almost two-thirds of boys, but only just over one-third of girls meeting the daily recommended level of moderate to vigorous activity. Time spent being sedentary was similar between 7-year-old boys and girls. There were large differences between 7-year-old children from different ethnic backgrounds, with the lowest levels of physical activity being found in Bangladeshi and Indian children. White, mixed race and Black children had similar levels of activity. In all ethnic groups, girls had significantly lower levels of physical activity than boys (Griffiths et al. 2013).

Table 14. Median time spent being sedentary, median time spent doing moderate to vigorous activity, and proportion of 7-year-old UK children meeting the recommended physical activity levels
 Sedentary time (hours/day)Moderate and vigorous activity (minutes/day)Percentage of children meeting recommended physical activity levels
Source: Griffiths et al. 2013.
All children6.460.150.8
Gender:   
Boys6.467.163.3
Girls6.554.437.8
Ethnicity:   
White6.560.251.4
Mixed6.862.251.5
Indian6.952.640.0
Pakistani6.458.245.2
Bangladeshi6.552.932.8
Black6.563.152.0
Other6.558.253.9
Country:   
England6.660.650.9
Wales6.561.651.7
Scotland6.461.852.5
Northern Ireland6.657.643.4

Levels of activity were similar in Scotland, Wales and England, but were lower in Northern Ireland. However, within England, there were significant variations in the proportion of 7-year-old children meeting the recommended 60 minutes of moderate to vigorous activity per day, ranging from 46.6% in the South East to 57.8% in the North West. Although there were no clear socio-economic gradients in physical activity levels and adherence to guidelines, there was a tendency for children whose mothers were never employed or currently unemployed to be slightly more active than children whose mothers were employed. Also, children of lone parents were slightly more active and more likely to meet the physical activity recommendations than those from two-parent families. However, overall, with the exception of gender, the differences observed were relatively small, and the most striking finding is the low level of activity across all groups (Griffiths et al. 2013).

Other data on physical activity levels from different parts of the UK

Country-specific data on physical activity levels are available, mainly from health reports. However, the findings of these are not directly comparable owing to use of different methodologies, a problem overcome by the Millennium Cohort Study. The 2008 Health Survey for England found that 32% of boys and 24% of girls aged 2–15 years met the target to be active for 60 minutes each day, although this includes only out-of-school activity. There was a clear effect of gender and age on physical activity levels, with boys generally being more active than girls, and activity levels dropping with age (see Fig. 5) (Craig et al. 2009b).

figure

Figure 5. Objectively measured activity levels of boys and girls age 4–10 and 11–15 years in England.

Meets recommendations: 60 minutes or more at least moderate activity on all 7 days; some activity: 30–59 minutes on all 7 days; low activity: lower levels of activity.

Download figure to PowerPoint

The Scottish National Health Survey 2011 found that 73% of children aged 2–15 years met the level of physical activity recommended in the UK (Bradshaw et al. 2012). The Welsh Health Survey 2011 reported that 39% of boys and 30% of girls aged 4–15 years were physically active (i.e. physical activity that left the child feeling warm or slightly out of breath) for at least 1 hour everyday (WG 2012). Northern Ireland does not have a comparable health survey. However, findings for the Young Persons' Behaviour and Attitudes Survey carried out at the end of 2010 suggest that 90% of young people aged 11–16 years in Northern Ireland played sport, exercised or played actively. Of these, 32% reported doing so for at least 60 minutes on five or more days (CSU 2011). See Weichselbaum and Buttriss (2011) for more details on the findings from the national surveys.

Influences on children's physical activity levels

Many factors influence children's physical activity habits and understanding these is the key to ensuring all children meet national recommendations. This is particularly important as research indicates that physical activity behaviours may track into adulthood (Malina 1996; Harro & Riddoch 2000) and, therefore, facilitating physical activity in childhood may be important in helping to set good behaviour early on.

Gender and age

That boys are more active than girls is a common observation and evidence to support this is provided by a number of studies in school-aged children, including the most recent Millennium Cohort Study (Inchley et al. 2005; Brodersen et al. 2007; Riddoch et al. 2007; Fairclough et al. 2012; Brooke et al. 2013; Griffiths et al. 2013). Also the types of activity differ between boys and girls, with one study in 9–10 year-old children from Norfolk finding that activity participation often reflected gender stereotypes (e.g. boys played more football and cricket, whereas girls spent more time being active with pets, skipping and dancing) (Brooke et al. 2013). A study in 10–11 year-old children from schools in northern England found that boys spent more time doing vigorous activities than girls, in particular during out-of-school time (Fairclough et al. 2012). In addition to gender, age is also found to affect activity levels, with the majority of research indicating that activity levels decline as children get older. In the Health Behaviour in Teenagers Study, which explored physical activity levels in schoolchildren (aged 11–12 years at baseline) from 36 London schools over a period of 5 years, the number of days of vigorous physical activity per week fell over the 5-year study period, and more so in girls than in boys. In contrast, hours of sedentary behaviour increased over the study period by an average of 2.5 hours per week in boys and 2.8 hours per week in girls (Brodersen et al. 2007). A series of studies in Scotland found that there was a consistent decrease in physical activity in girls with increasing age, but no consistent trends could be observed in boys (Inchley et al. 2005; Bromley et al. 2010). In the 2008 Health Survey for England, activity levels decreased with age in both boys and girls, but were generally lower in girls (see Fig. 5) (Craig et al. 2009b).

Ethnicity

The findings of the Millennium Cohort Study in 7-year-old children reveal significant differences in activity levels between different ethnic groups; see section ‘Current activities in children across the UK’ and Table 14 for more details (Griffiths et al. 2013). Differences between ethnic groups were also reported previously. In the Health Behaviour in Teenagers Study, ethnicity was classified, by self-reporting, as either White, Black or mixed Black, or Asian or mixed Asian. Asian students of both sexes reported being less physically active than their White counterparts (P < 0.001), whereas for Black students, lower activity levels were seen only among Black girls when compared with White girls. However, Black students of both sexes reported higher levels of sedentary behaviour than their White peers, the difference being greater in girls. Trends in sedentary behaviour also differed between White and Asian girls, with increasing sedentary behaviour occurring at younger age in Asian girls (Brodersen et al. 2007).

The 2004 Health Survey for England's report on the Health of Minority Ethnic Groups found that most ethnic minority groups had lower activity levels than the general population, with clear differences between the various ethnic groups (Sproston & Mindell 2006). For more detail see Weichselbaum and Buttriss (2011).

A recent study in children aged 8–9 years attending primary schools in Coventry used combined physical activity and heart rate monitors for 7 days to identify differences in activity levels between White European (n = 96) and South Asian children (n = 65). A significant difference in activity levels was observed between the two groups, with 73% of White Europeans meeting the recommended 60 minutes of moderate to vigorous physical activity daily, compared with only 35% of South Asians. South Asians were less active during the week and at weekends. The differences in activity levels were mainly attributable to physical activity carried out after school (Eyre et al. 2013).

Socio-economic status (SES)

The Millennium Cohort Study found no clear socio-economic gradients in physical activity levels or adherence to physical activity guidelines (see section ‘Current activity levels across the UK’) (Griffiths et al. 2013). In a sample of 1700 children aged 9–10 years, Brooke et al. (2013) found that children whose parent/guardian was in the highest educational group reported participating in activities less frequently than children whose parent/guardian had a low education level. These findings are in contrast to findings of previous surveys. For example, in the Health Behaviour in Teenagers Study, no association between SES and physical activity was found in boys, but girls from lower SES households were less active than those from higher SES households. Sedentary behaviour levels were greater in boys and girls from low socio-economic neighbourhoods, the difference being greater in girls than boys (Brodersen et al. 2007). The LIDNS also found lower physical activity levels in children within the low-income population than children from the general population (Sproston & Primatesta 2003; Bromley et al. 2005; Nelson et al. 2007). However, the 2008 Health Survey for England (Craig et al. 2009b) and the Scottish National Health Survey 2009 (Bromley et al. 2010) have found either no association, or higher levels of activity associated with lower SES, supporting findings from more recent surveys. It is unclear why there are discrepancies in the data, but methodological differences are likely to have contributed to these variations. Research has suggested that the type of activity may also differ, with children from a lower socio-economic background tending to participate in unstructured activities or free play, whereas children from higher SES groups are more likely to take part in structured activities or belong to sports clubs (Brockman et al. 2009).

Family and peer influence

The role of family, in particular role modelling and parental support (e.g. facilitating activity by providing transport or financial support), in influencing children's activity levels has received increasing attention in recent years. However, the extent of parental and peer influence is still uncertain. A study in 180 9-year-old girls examined the extent to which parents' activity-related parenting practices influenced the girls' physical activity levels (Krahnstoever Davison et al. 2003). In families where both parents provided a high level of overall support for their daughter's activities, 70% of girls were classified as being highly active, compared with 56% in families where only one parent showed a high level of overall support and 32% of girls in families in which neither parent provided a high level of overall support. The type of support given differed between fathers and mothers; fathers supported their daughters more through role modelling, whereas mothers acted more as facilitators by providing logistic support; the impact of both kinds of support on girls' activity levels seemed to be similar (Krahnstoever Davison et al. 2003). In another study, parent inactivity was a strong and positive predictor of child inactivity, whereas scores of parent activity were somewhat weaker predictors of a child's vigorous activity and total physical activity level (Fogelholm et al. 1999). A study by Brockman et al. (2009) found that the SES of the family may influence the level and type of support given. Children from schools in middle/high SES areas received more logistical and financial support, whereas parents of children from schools in low SES areas (lowest third of SES status defined by the Index of Multiple Deprivation, a UK government-produced measure of deprivation) mainly restricted their input to verbal encouragement and demands on the children (e.g. ‘Get off the sofa and go and play’). Participation in family-based activities was reported to be higher in children from schools in middle/high SES areas than children from schools in low SES areas. Cost was reported as a significant barrier by children from schools in low SES areas (Brockman et al. 2009). The Scottish and English health surveys also looked at the relationship between parents' physical activity levels and physical activity levels of their children, resulting in different outcomes. In the 2008 Health Survey for England (Craig et al. 2009b), younger boys (2–10 years) were more likely to meet the physical activity recommendations if their parents were also physically active, whereas in older boys (11–15 years) only the fathers' activity levels seem to have an influence. Among girls, the activity level of parents made relatively little difference to the proportion meeting the recommendations. Similarly, for both age groups of boys and girls, more were in the low activity category if their parents were also in this category (Craig et al. 2009b). In the Scottish National Health Survey, boys and girls whose mothers met physical activity recommendations were more likely to meet the recommendations themselves, whereas this pattern was not apparent in relation to the fathers' physical activity levels (Bromley et al. 2010). More research is needed to understand the differences between studies.

A study carried out in a cohort of 315 9–13 year-olds from schools across London sought to determine the influence of peers (‘friends’) on physical activity levels. Activity levels were recorded using a 3-day diary and pedometer. Peer influence was assessed using a Social Support and Eating Habits/Exercise Survey and there was a significant correlation between the number of steps taken and friends taking part in physical activity or exercise with the study subject, and friends discussing physical activity or exercise with the subject (Finnerty et al. 2010). Jago et al. have suggested that promoting physical activity via friendship groups may be one way to increase activity levels among children (Jago et al. 2009).

Physical environment

The environment in which we live has received increasing attention over recent years in terms of the role it plays in influencing physical activity levels of individuals. The characteristics of the built environment are often cited as a cause of inactivity. In particular, an increasing reliance on car use in place of walking and cycling, concerns over safety, and a lack of green space are commonly cited as barriers to being physically active (Butland et al. 2007; Dunton et al. 2009). Indeed, busy traffic and a neglect of local play areas have both been identified as barriers to children's participation in physical activity (Brunton et al. 2003). However, a recent systematic review comparing the physical activity levels of children living in different built environments did not find major differences between children from rural and urban areas (Sandercock et al. 2010).

Travel to school

Findings from the East of England Healthy Hearts Study, comprising data from 6085 schoolchildren aged 10–16 years, suggest that mode of travel to school may be associated with physical fitness in schoolchildren. Those walking or cycling to school were significantly more likely to be classified as ‘fit’ compared with children using passive travel modes (i.e. car or public transport). This significant difference remained after adjusting for general physical activity levels in girls, but not in boys (Voss & Sandercock 2010).

Sedentary behaviour

Sedentary behaviour refers to activities that do not increase energy expenditure substantially above the resting level; these include screen-based behaviours such as TV viewing and playing computer games, as well as activities such as reading and listening to music, and sitting and lying down (Pate et al. 2008; BHF 2009). A recent review found that out of nine studies, seven reported a link between sedentary behaviour and bodyweight in children; those spending more time being sedentary had higher bodyweights. Interestingly, the two studies that did not find an association were the only studies using objectively measured data rather than relying on self-reported activity levels (Prentice-Dunn & Prentice-Dunn 2012). More studies with objectively measured levels of sedentary behaviour are needed to improve understanding of this relationship.

The association between sedentary behaviour and obesity may be complex and may not be as simple as sedentary behaviours directly displacing physically active ones. An increase in sedentary behaviour may not just mean fewer calories are expended; evidence indicates that activities such as television viewing are often associated with negative eating habits, including the consumption of energy-dense food and drinks (Vereecken et al. 2006; Reilly 2008), thereby exacerbating the problem. Evidence from intervention studies in children show that a reduction in sedentary behaviour results in improvement in weight parameters, although the magnitude of change is modest and difficult to interpret (DeMattia et al. 2007).

The benefits of limiting sedentary behaviour are reflected in the UK physical activity guidelines (see ‘Recommendations in the UK’ earlier), where it is stated that all children and young people should minimise the amount of time spent being sedentary (sitting) for extended periods (Chief Medical Officers 2011).

Data from the Millennium Health Study show that the median time spent on sedentary activities by 7-year-old children in the UK is 6.4 hours per day, with little differences by gender, ethnicity or country (Griffiths et al. 2013). The 2008 Health Survey for England also examined sedentary time (excluding at school) in children and reported that boys and girls spend an average of 3.4 hours on weekdays and 4.1 hours on weekend days being sedentary (excluding school or sleeping time), with the average time increasing with age (Craig et al. 2009b). A further study on sedentary behaviour in 923 teenage girls (12–17 years) from secondary schools in 15 regions within the UK reported that the five most time-consuming sedentary activities occupied on average 4.4 hours per weekday and 6.7 hours per weekend day. This is in contrast to just 44 minutes per weekday and 53 minutes per weekend devoted to active transport or sports and exercise (Gorley et al. 2007).

Overall, although the studies used different methods to evaluate physical activity, which limits interpretation and direct comparison between studies, it is clear that many children do not meet the recommendations for physical activity. In particular, girls appear less active than boys, a gap that widens as they grow older. In addition, low levels of physical activity have been observed in certain ethnic minority groups. These differences highlight the need for targeted interventions to improve activity levels among those with particularly low levels, as well as encouragement to be more active in general.

Overweight and obesity

Classification of overweight and obesity

In both adults and children, appropriate weight-for-height is most frequently described using BMI, determined by dividing weight (kg) by height squared (in metres). For adults, cut-offs for overweight and obesity are 25 and 30 kg/m2, respectively (WHO 2000). These cut-offs are not applicable to children because the ratio of velocity of weight gain to that of height gain changes during normal growth, especially around puberty. Therefore, age- and sex-specific reference data (centile cut-off points on charts) are necessary to interpret measurements of children. For children in the UK, new national reference growth charts for child-specific BMI values were published in June 2013 and are available on the website of the Royal College of Paediatrics and Child Health (www.rcpch.ac.uk/growthcharts). These combine data from the UK 1990 growth references for children at birth and at ages 4–18 years (Cole et al. 1995) with the WHO growth standards for children aged 2–4 years. The 85th percentile and the 95th percentile, respectively, are used to identify overweight and obesity in both the Health Survey for England and the National Child Measurement Programme, a governmental initiative to measure schoolchildren in Reception (aged 4–5 years) and Year 6 (aged 10–11 years) (DH 2008; Craig et al. 2009a; HSCIC 2012).

The International Obesity Task Force (IOTF) has put forward an alternative approach derived from data collected in children from six countries. The IOTF links BMI values at 18 years to child centiles, which are averaged across the countries. Unlike other BMI references, these cut-offs cannot be expressed as centiles (e.g. 85th). New cut-offs were recently published, but these were virtually identical to those published previously (Butland et al. 2007; Cole & Lobstein 2012). These growth references are useful for international comparison of overweight and obesity in children. However, for studies on the prevalence of overweight and obesity in the UK, the growth charts that combine UK specific data with charts developed by the WHO are generally still the preferred choice and are being used in various health surveys as mentioned above.

Prevalence of overweight and obesity

The Health Survey for England provides data on trends in overweight and obesity in children throughout England from 1995 to 2011. In this survey, overweight was defined as a BMI between the 85th and 95th percentiles, and obesity was defined as a BMI above the 95th percentile (Craig & Mindell 2012). Prevalence rates of overweight and obesity in England in 2011 compared with 1995 are shown in Table 15.

Table 15. Prevalence of overweight (>85th–95th percentile) and obesity (>95th percentile) in English children aged 2–15 years, 1995 and 2011
 19952011
2–10 years11–15 years2–10 years11–15 years
Source: Health Surveys for England (Craig & Mindell 2012).
Boys:    
Overweight13.1%13.9%14.9%14.6%
Obese9.7%13.9%12.4%23.8%
Total: overweight and obesity22.7%27.8%27.4%38.4%
Girls:    
Overweight12.8%14.3%8.7%19.2%
Obese10.6%15.5%15.5%16.5%
Total: overweight and obesity23.4%29.8%24.3%35.7%

Table 15 and Figures 6 and 7 show that changes in overweight and obesity rates between 1995 and 2011 were mainly due to changes in rates of obesity; overweight rates remained relatively stable. Combined overweight and obesity rates have increased in boys of both age groups up until around 2005. They have continued to increase in boys aged 11–15 years, whereas the prevalence has levelled off or even decreased slightly, in boys aged 2–10 years. In girls, similar trends have been observed, but rates have generally increased to a lesser degree than in boys (Craig & Mindell 2012).

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Figure 6. Overweight and obesity rates in English boys aged 2–15 years (1995–2011).

Adapted from Craig and Mindell 2012.

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Figure 7. Overweight and obesity rates in English girls aged 2–15 years (1995–2011).

Adapted from Craig and Mindell 2012.

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Inequalities according to SES were found in both boys and girls, with obesity levels being highest among boys in the lowest quintile of income, and among girls in the third and lowest income quintiles. The proportion of children who were obese was also higher among those living in the most deprived compared with the least deprived areas, in both boys (29% vs. 11%, respectively) and girls (22% vs. 10%, respectively) (Craig & Mindell 2012). Socio-economic inequalities were also found within the National Child Measurement Programme (which is described later). There was a linear, inverse relationship between deprivation and obesity (see Fig. 8). In children aged 5, obesity prevalence ranged from 6.8% (in the least deprived) to 12.3% in the most deprived. In the older age group (11-year-olds), obesity prevalence had risen to 13.7% in the least deprived group and to 24.3% in the most deprived. Figures 9 and 10 show that the difference by deprivation decile is only obvious for obesity, and not for overweight, at ages 5 and 11 years.

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Figure 8. Prevalence of obesity by deprivation decile in children aged 5 years (Reception) and 11 years (Year 6).

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Figure 9. Prevalence of overweight and obesity in Reception (age 5 years) by deprivation decile.

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Figure 10. Prevalence of overweight and obesity in Year 6 (age 11 years) by deprivation decile.

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The school-based, National Child Measurement Programme, mentioned earlier, records height and weight of children living in England aged 4–5 years and 10–11 years and is another source of data on obesity prevalence; the programme started in the school year 2006/2007 and data is available up to school year 2012/2013. In contrast to the Health Survey for England, where a sample of children representative of the population is measured, in this programme the aim was to measure all children in Reception and Year 6 classes. The programme uses the same cut-off points as the Health Survey for England. Data from the report from school year 2011/2012 (Table 16) show that obesity rates are higher in boys than girls and clearly increase (almost double) between Reception and Year 6, in both boys and girls. Compared with school year 2006/2007, prevalence rates of overweight and obesity in Reception have hardly changed, except for a lower prevalence of obesity in boys in 2011/2012 compared with 2006/2007. In Year 6, rates of overweight, and in particular, obesity have increased between 2006/2007 and 2011/2012 (HSCIC 2012).

Table 16. Prevalence of overweight and obesity in English schoolchildren in Reception and Year 6 classes in school years 2006/2007 and 2011/2012, National Child Measurement Programme
 Overweight (%)Obese (%)
2006/20072011/20122006/20072011/2012
Source: HSCIC 2012.
Reception (age 4–5 years)Boys13.613.610.79.9
Girls12.412.59.09.0
Year 6 (age 10–11 years)Boys14.214.719.020.7
Girls14.114.715.817.7

In December 2013, the statistics for 2012/2013 (representing over a million children in England; 93% of the possible sample) were published and revealed a slight fall in the prevalence of childhood overweight and obesity in Reception and Year 6. Obesity prevalence in Reception fell to 9.3% compared to 9.5% in 2011/2012 and the combined prevalence of overweight and obesity to 22.2% from 22.6%. In Year 6, obesity fell from 19.2% to 18.9%, compared to 2011/2012, and combined prevalence of overweight and obesity from 33.9% to 33.3%. This is the first fall in prevalence since the National Child Measurement Programme (NCMP) began in 2006/2007; it is not yet known whether this is the start of a decline. There was no difference in the proportion of children who were underweight in either age group. As in previous years, a strong positive relationship existed between deprivation index and obesity prevalence, reaching 12.1% and 24.2% in the most deprived deciles of Reception and Year 6 children respectively (compared to 6.4% and 12.1% respectively in the least deprived deciles). For each age group, obesity prevalence was significantly higher than the national average in Black/Black British, Asian/Asian British, for example, and was significantly higher in urban than rural areas.

The Scottish Health Surveys use the same cut-off points and reference values as the English surveys to define overweight and obesity in children. Data from 2011 are shown in Table 17 (Bradshaw et al. 2012).

Table 17. Prevalence of overweight (>85th–95th percentile) and obesity (>95th percentile) in Scottish children aged 2–15 years in 2011
 2–6 years (%)7–11 years (%)12–15 years (%)
Source: Bradshaw et al. 2012.
Boys:   
Overweight17.618.414.8
Obese15.718.218.9
Total: overweight and obese33.336.633.7
Girls:   
Overweight16.011.517.6
Obese11.916.013.1
Total: overweight and obese27.927.530.7

Figure 11 shows that whereas the percentage of girls in Scotland who are overweight or obese has not changed considerably over the period 1998–2011, there are fluctuations in the total prevalence of overweight and obesity in boys. There was a notable difference between the years 2008 and 2009, which the authors of the study suggest may reflect sample fluctuation rather than a true population difference. However, it is still clear that there has been an increase in the prevalence of overweight and obesity combined over the past decade in boys in Scotland.

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Figure 11. Total prevalence of overweight and obesity (combined) in Scotland for children aged 2–15 years in 1998, 2003, 2008, 2009, 2010 and 2011.

Adapted from Bradshaw et al. 2012.

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Data from the 2011 Welsh Health Survey show that 16% of boys aged 2–15 years were overweight and a further 21% were obese, and 16% of girls were overweight and 18% obese (WG 2012). There were no obvious trends in the prevalence of overweight and obesity between 2007 and 2011 (Fig. 12).

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Figure 12. Prevalence of overweight and obesity in Wales for children aged 2–15 years in 2007–2011.

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In contrast to other UK countries, the Health Survey Northern Ireland (2011–2012) used the guidelines of the IOTF to define overweight and obesity, which means prevalence rates are not directly comparable with other UK countries. The survey found that 10% of boys and girls aged 8–15 years were obese, and 21% were classed as overweight (DH, SSPS 2012).

Obesity and ethnicity

Child obesity prevalence has been shown to vary substantially between ethnic groups, for example in the Health Survey for England (Sproston & Mindell 2006). Recent data from the National Child Measurement Programme shows obesity prevalence to be especially high among children of both sexes from Black and Black British ethnic groups (15.5% in Reception and 27.5% in Year 6), followed by Asian/Asian British ethnic groups (10.4% in Reception and 23.4% in Year 6). The lowest prevalence of obesity was found in children of Chinese background (7.3% in Reception and 16.7% in Year 6) and children from the White ethnic group (8.9% in Reception and 18.1% in Year 6) (HSCIC 2012). The National Obesity Observatory has summarised data on overweight and obesity in ethnic groups in England in a recent report (see Ridler et al. 2013).

Future trends in children

The Foresight report on obesity, produced by the UK government's Foresight Programme and published in 2007, presented projections on future obesity trends in children. It was suggested that, if trends of previous years were to continue, prevalence rates of obesity in children would rise two- to threefold between 2004 and 2050 (Butland et al. 2007). However, recent data reviewed here suggest that overweight and obesity rates in children, especially in the younger age group, may be levelling off. Revised projections are not yet available.

Development of childhood obesity

Obesity occurs when energy intake remains higher than energy expenditure, for an extended period of time. This means that more energy from food and drinks than the body uses has been consumed over a period of time, and in order to halt weight gain or lose weight, either less energy from food and drinks needs to be eaten or more energy needs to be used by increasing the level of physical activity, or a combination of both. Nevertheless, in reality, obesity is a complex condition and biology, eating and physical activity behaviours, people's beliefs and attitudes, and broader economic and social drivers all have a role to play, as illustrated in the Foresight report on this topic (Butland et al. 2007). Environmental factors such as the ready availability of energy-dense foods and drinks and limited opportunities for being physically active can contribute to the development of overweight and obesity; this is often referred to as an ‘obesogenic environment’. The pattern of growth during early life is also a determinant of future risk of obesity. There is evidence that weight gain in early life, particularly catch-up growth in low-birthweight babies, is associated with a higher risk of overweight and obesity in later life. Also an early so-called ‘adiposity rebound’ in childhood (the period of time in early childhood when the ratio of bodyweight to height falls and then rises again) predicts a higher BMI later on (Butland et al. 2007). The interrelationship between early life nutrition and bodyweight in later life is discussed in detail in a BNF Task Force report (BNF 2013). To tackle obesity levels in children and adolescents, the various contributing factors need to be taken into account rather than simply addressing one factor.

Health implications of overweight and obesity

Overweight and obesity are associated with an increased risk of various conditions, including CVD, type 2 diabetes, high blood pressure, some cancers and problems with the musculoskeletal system. Diseases such as heart disease and stroke typically occur in adulthood, but obese children often display many of the changes associated with vascular disease in adults, including insulin resistance, high blood pressure, elevated total cholesterol, triglycerides, LDL-cholesterol and oxidised LDL-cholesterol, and reduced high-density lipoprotein (HDL) cholesterol (e.g. Larson Ode et al. 2009; Short et al. 2009; Steinberger et al. 2009; Barton 2012; Dhuper et al. 2013). Insulin resistance is the most common metabolic alteration related to obesity, and obesity is the major risk factor for the development of insulin resistance in children and adolescents. Insulin resistance represents an important link between obesity and other metabolic as well as cardiovascular complications (Chiarelli & Marcovecchio 2008; Nathan & Moran 2008) and is thought to be a key risk factor in the development of lipid abnormalities. At the same BMI, adolescents with evidence of insulin resistance are more likely to have an abnormal lipid profile (Nathan & Moran 2008; Larson Ode et al. 2009). Evidence suggests that waist circumference in children is an independent predictor of insulin resistance (Chiarelli & Marcovecchio 2008; Nathan & Moran 2008; Steinberger et al. 2009; Rodriguez-Rodriguez et al. 2011). Considered previously to be a disease of adults, type 2 diabetes has become a far more common occurrence in children and adolescents over the last decade. Depending on the ethnic composition of the population, between 8% and 50% of newly diagnosed adolescent diabetic patients have type 2 diabetes (Steinberger et al. 2009), the remainder being type 1 and other forms of diabetes.

Obese children also have a higher risk of impaired endothelial function, lower arterial compliance and elasticity, and increased intima-media thickness (Short et al. 2009; Steinberger et al. 2009), which are measures of vascular health and associated with adverse cardiovascular events in adulthood. Autopsy studies in children and adolescents have also shown that the extent of early atherosclerosis of the aorta and coronary arteries is directly associated with levels of lipids, blood pressure and obesity (Steinberger et al. 2009). Obesity is also a well-established risk factor for hypertension in children (Nathan & Moran 2008; Larson Ode et al. 2009; Flynn & Falkner 2011).

In addition to the negative impact of obesity on factors associated with CVD, multiple studies have suggested that childhood overweight and obesity track into adulthood (Steinberger et al. 2009; Biro & Wien 2010; Lloyd et al. 2010). Overweight children are more prone to becoming overweight adults, especially at higher BMIs or if they have an obese parent (Steinberger et al. 2009; Biro & Wien 2010). Important evidence for this comes from a US study (the Bogalusa Heart Study) that began in 1972 and has followed many participants from childhood into adulthood; the outcomes of this study show that children who were overweight at age 2–5 years were over four times more likely to become obese than those with a BMI < 50th percentile (Freedman et al. 2005). In this study, childhood triceps skinfold thickness, a measure of body fat, provided only a slightly stronger association with adult adiposity than childhood BMI (Freedman et al. 2005), which itself does not directly measure body fatness. There were similar outcomes in a retrospective school-based cohort study that followed up 1520 men born between 1927 and 1956 from the age of 9–18 years into adulthood (average 63 years). Childhood BMI correlated strongly and positively with adult adiposity, as measured by BMI, and adult waist and hip circumferences (Sandhu et al. 2006). Data from a UK cohort (Thousand Families Cohort Study, comprising 1142 children born in 1947 and followed up into adulthood) showed a moderate, statistically significant correlation between childhood and adult BMI. At age 50, those who had been above the 90th centile for BMI at age 9 or 13 years were between five and nine times more likely to be obese than those in the thinnest quartile in childhood. The association between childhood BMI and percentage of body fat in adulthood was weaker than that with adult BMI. Most of those in the top quarter for body fat aged 50 years had not been overweight as children: 94% had been below the 90th percentile for BMI at age 9 and 79% at age 13 (Wright et al. 2001). It should be noted that around 50 years ago, overweight in children was not as common as today and most children were of normal weight. The outcomes of this study indicate that although those who are overweight or obese in childhood have an increased risk of being overweight and obese as adults, thinness in childhood does not protect from overweight and obesity in adulthood.

Children who are obese are more likely to already have cardiovascular risk factors, including insulin resistance, lipid abnormalities and high blood pressure, and are more likely to be overweight and obese as adults. However, the question is whether childhood obesity is an independent risk factor of disease in later life. If it is, this would mean that being overweight at a young age automatically increases the risk of disease in adulthood, even if the weight status changes, and that thinness in childhood decreases the risk of disease in adulthood, even if people later become overweight in adulthood. Authors of several systematic reviews have concluded that although there is consistent evidence to suggest that childhood obesity is associated with risk factors for CVD in adulthood, there is little evidence that overweight and obesity in childhood are independently associated with risk of increased blood pressure, carotid-intima thickness, insulin resistance and diabetes, metabolic syndrome or CVD morbidity or mortality in adulthood, suggesting that increased risk is mainly due to overweight and obesity tracking into adulthood (Lloyd et al. 2010, 2012; Park et al. 2012). In fact, when adjustment was made for adult BMI, there was a weak negative association between childhood BMI and metabolic variables; at particular risk were those at the lower end of the BMI range in childhood but who were obese during adulthood (Lloyd et al. 2012). Indeed, findings of the Thousand Families Cohort Study suggest that those thinnest in childhood, but overweight in adulthood, have the highest overall risk of adult disease (Wright et al. 2001).

In summary, evidence does not suggest that overweight and obesity in childhood are independent risk factors of adult disease. However, it is important not to underestimate the potential problems childhood overweight and obesity may cause in later life because of the potential for tracking into adulthood. Overweight and obesity in adulthood are established risk factors for various diseases, including hypertension, CVD, type 2 diabetes, some cancers, arthritis, asthma, and other respiratory diseases. Fetal programming of metabolic function induced by maternal obesity supports intergenerational effects on obesity and associated conditions. Obesity during pregnancy also carries risks for both the mother and child, emphasising the importance of preventing obesity in adolescent girls and young women (BNF 2013).

Prevention and management of childhood obesity

Treatment of established obesity can prove difficult and therefore much more effort should be put into obesity prevention, but contrasting findings have emerged from systematic reviews. A Cochrane review failed to demonstrate that diet and exercise interventions are effective in preventing weight gain and obesity in children but found that they can be effective in promoting a healthy diet and increased physical activity levels (Summerbell et al. 2005), but another systematic review (and meta-analysis) reported that a combination intervention, a single nutrition intervention and a TV reduction intervention were equally effective in achieving weight reduction compared with controls, although a physical activity intervention alone was not effective (Katz et al. 2008). A systematic review of community-based childhood obesity prevention programmes found that out of nine studies, only four resulted in significant changes in BMI (Bleich et al. 2013). Those studies that found significant changes were characterised by a relatively longer follow-up period, a focus on younger children and included settings other than just the community. In particular, interventions that included a school component and focused on both diet and physical activity were effective in preventing overweight or obesity. Another systematic review found that home-based childhood obesity interventions have not resulted in a significant effect on weight outcomes (Showell et al. 2013).

A programme aiming to prevent overweight and obesity is the ‘Ensemble Prévenons l'Obésité des Enfants’ (EPODE, Together Let's Prevent Childhood Obesity) programme, which started in France and has been rolled out to other European countries. EPODE methodology promotes the involvement of multiple stakeholders at two levels: (1) at a central level (ministries, health groups, non-governmental organizations and private partners); and (2) at local level (political leaders, health professionals, families, teachers, local non-governmental organizations and the local business community). Early evaluation of the EPODE methodology suggests encouraging results, but further potential lessons are to be learned from a detailed evaluation of EPODE (for more information, see Borys et al. 2012).

In an EU-funded study, ToyBox, an innovative and evidence-based obesity prevention programme for children aged 4–6 years is being developed that promotes healthy food, fun and active play in preschool settings throughout Europe (www.toybox-study.eu). The study has confirmed findings by Bleich and colleagues (2013) that interventions are most effective if they include long-term follow-up, target both physical activity and dietary change, and comprise interactive school-based learning combined with high levels of parental involvement (Nixon et al. 2012).

Another systematic review found that, when implemented alone, school-based diet and physical activity related policies appear insufficient to prevent or treat overweight or obesity in children, but that they do appear to have an effect when developed and implemented as part of a more extensive intervention programme that aims to influence behaviour at multiple levels (e.g. home, school, neighbourhood) (Williams et al. 2013).

For the prevention of excess weight gain, it is crucial to emphasise the importance of a healthy balanced diet as well as adequate physical activity levels from an early age, with the focus being on general health and wellbeing rather than obesity prevention. Schools have an important role to play here as they provide an environment where consistent healthy eating messages can be applied as part of a whole school approach (see sections ‘Food provision in school’ and ‘Food in the curriculum’), but the greatest impact seems to occur when a broader approach is taken.

A small number of intervention studies have found an effect of non-clinical interventions on the bodyweight of children and adolescents, although most studies had major limitations (NICE 2006b). In its guidance, the National Institute of Clinical Excellence (NICE) focuses on prevention rather than management of obesity in non-clinical settings (e.g. schools). For management of obesity, NICE suggests that multi-component interventions are the treatment of choice; weight management programmes (either for weight maintenance or loss, depending on age and stage of growth) should include behaviour change strategies to increase physical activity levels or decrease inactivity, improve eating behaviour and diet quality, and reduce energy intake. Interventions should address lifestyle within the family and also social settings. NICE also emphasises that if help is offered at school, confidentiality and building self-esteem are particularly important because treating children for overweight or obesity may stigmatise them and put them at risk of bullying, which in turn can aggravate problem eating (NICE 2006a). More recently published evidence-based guidance, which complements the general obesity guidance, specifically deals with lifestyle weight management programmes and helps commissioners in local authorities and the NHS and providers of community-based services in their planning of such programmes. The report recognises the importance of including the whole family in lifestyle intervention programmes, i.e. to encourage other family members to also adjust their eating and lifestyle habits, be aware of what is important for the child, and take an active role in improving the lifestyle of a child (NICE 2013).

The guidelines for management of obesity in children from the Scottish Intercollegiate Guidelines Network (SIGN) are similar to those from NICE. SIGN suggests that treatment programmes for managing childhood obesity should incorporate behaviour change components, be family-based involving at least one parent/carer, and aim to change the whole family's lifestyle. SIGN also suggests that for most obese children, weight maintenance is an acceptable treatment goal. Orlistat should only be prescribed for severely obese adolescents with co-morbidities or those with very severe to extreme obesity attending a specialist clinic, whereas bariatric surgery can be considered for post-pubertal adolescents with very severe to extreme obesity and severe co-morbidities (SIGN 2010).

Cardiovascular risk factors

CVD is a major cause of adult death and ill health. Autopsy studies have revealed first signs of atherosclerosis to already be prevalent in childhood and it has therefore been suggested that the disease process begins in this age group (Celermajer & Ayer 2006). Autopsy studies have also shown that the extent and severity of arterial fatty streaks or raised plaques is associated with raised levels of blood lipids, blood pressure and obesity in childhood and adolescents (Celermajer & Ayer 2006; Steinberger et al. 2009). Obesity is a major influence in the development of cardiovascular risk factors in childhood, including hypertension, dyslipidaemia and diabetes mellitus; and its role is discussed in more detail in the previous section.

A strong positive association between total and LDL-cholesterol and CVD, as well as an inverse relationship between HDL-cholesterol and CVD in adults, has been established in a number of major epidemiological studies. As cholesterol concentrations track over time, it is observed that children with unfavourable cholesterol concentrations are more likely to have unfavourable cholesterol concentrations as adults (Celermajer & Ayer 2006). Obese children and those with insulin resistance have an increased risk of dyslipidaemia (Steinberger et al. 2009). Although more evidence is needed to clarify the effect of childhood blood cholesterol concentrations on future CVD risk, public health strategies should aim to maintain cholesterol concentrations at a healthy, low level in all children.

Diabetes mellitus

Diabetes mellitus is a metabolic disease that is characterised by hyperglycaemia (raised blood glucose) and is associated with accelerated development of vascular disease. Hyperglycaemia is the result of either impaired secretion of insulin (type 1 diabetes), resistance to the effect of insulin in the liver or muscles (type 2 diabetes), or a combination of these (Steinberger et al. 2009). Type 1 diabetes is an autoimmune disease where the insulin producing cells are destroyed and insulin needs to be injected. In contrast, type 2 diabetes is mainly found in association with overweight and obesity, and treatment generally includes changes in lifestyle, including eating a healthy diet, increasing physical activity and losing weight.

The most frequent type of diabetes mellitus in children and young people is type 1 diabetes, although type 2 diabetes – which is typically a disease of adults – is now being diagnosed in obese children and adolescents. The prevalence of both forms of diabetes in children and adolescents has increased during recent decades (Aylin et al. 2005; Haines & Kramer 2009; Hsia et al. 2009). A recent estimate of prevalence in children aged 0–17 years is 186 per 100 000 for type 1 diabetes and 3 per 100 000 for type 2 diabetes (Haines & Kramer 2009). Most children with diabetes are 10 years or above; 77% of all children with type 1 and 98% with type 2 are in this age group (Haines & Kramer 2009).

Type 2 diabetes is more prevalent in some ethnic groups than others. A recent study showed that the presence of type 2 diabetes precursors in children also differs between ethnic groups living in the UK (Whincup et al. 2010). Compared with White Europeans, South Asian children have higher levels of type 2 diabetes precursors; this is also seen, to a lesser extent, in Black African-Caribbean children (Whincup et al. 2010).

Hypertension

Hypertension is a well-established risk factor for CVD in adults. Evidence shows that children who develop hypertension are more likely to be hypertensive as adults, and hypertension in childhood is a risk factor associated with early atherosclerotic change (Larson Ode et al. 2009; McCrindle 2010). A well-established risk factor of primary hypertension in children and adolescents is obesity (Celermajer & Ayer 2006; Larson Ode et al. 2009; Steinberger et al. 2009; McCrindle 2010; Flynn & Falkner 2011). Studies in the USA have shown that there is an association between the prevalence of both pre-hypertension and hypertension in children and incidence of overweight and obesity (see section ‘Overweight and obesity’) (McCrindle 2010). No data on prevalence of pre-hypertension and hypertension in children is available for the UK.

Management of primary hypertension in children and adolescents should focus on lifestyle changes that help with weight loss, including eating a healthy diet, being more physically active and spending less time being physically inactive. In terms of diet, a recent meta-analysis of 10 controlled trials, including almost 966 children, concluded that a modest reduction in salt intake was associated with significant reductions in systolic and diastolic blood pressure (He & MacGregor 2006). See section ‘Nutritional requirements of schoolchildren’ for target salt intakes in schoolchildren, and section ‘Findings of the National Diet and Nutrition Survey’ for average salt intakes in schoolchildren. Intake data suggest that salt intakes are too high, in particular in younger children (Adamson et al. 2011), but urinary sodium excretion is a more reliable marker. Data for children is expected to be published in the next NDNS report.

Iron deficiency anaemia

Anaemia is a global public health problem affecting both developing and developed countries. It is estimated that around 25% of the world's population has anaemia (around half of which is iron deficiency anaemia) (WHO 2008). The highest prevalence of anaemia is in pre-school children (<5 years), with an estimated 43% being affected worldwide (11% in high-income regions, 26% in central and eastern Europe) (Stevens et al. 2013), whereas the worldwide prevalence of anaemia in older children and adolescents is estimated to be approximately 25% (no data for Europe) (WHO 2008). The main risk factors for iron deficiency and iron deficiency anaemia are low intake of iron, poor iron absorption (from diets high in phytate or phenolic compounds, or low in ascorbic acid and meat/fish), periods of life when iron requirements are especially high (e.g. growth and pregnancy), heavy blood loss as a result of menstruation, and acute and chronic infections (WHO 2008; Falkingham et al. 2010). The presence of other micronutrient deficiencies, including vitamins A and B12, folate, riboflavin and copper can also increase the risk of anaemia (WHO 2008).

Iron requirements rise once menstruation starts and iron intakes are particularly poor in British girls aged 11–18 years, with 46% having iron intakes below the LRNI (Bates et al. 2012). By comparison, insufficient iron intakes were found in only 6% of boys of this age, and 1% of 4–10 year-old boys and girls (Bates et al. 2012; see section ‘Nutritional requirements of schoolchildren’).

Around 90% of iron in the UK diet is present as non-haem iron. The remainder exists as haem iron, which is found almost entirely in foods of animal origin. Haem iron is generally well-absorbed in the intestines. The extent to which non-haem iron is absorbed is principally influenced by systemic iron needs; more iron is absorbed from the diet in a state of iron deficiency and less is absorbed when iron stores are replete. Evidence, mainly from single meal studies, suggests that iron absorption is also influenced by the presence of other components in the diet (e.g. vitamin C and meat enhance absorption, phytates and phenolic compounds inhibit absorption). Evidence from whole diet studies over a number of days or weeks suggests that the overall effect of enhancers and inhibitors on iron absorption is considerably less than predicted from single meal studies (SACN 2010).

The 2012 findings of the NDNS Rolling Programme suggest that 30% of 11–18 year-old girls have low plasma ferritin levels (marker for long-term iron intake) and 9% of girls have low haemoglobin levels (indicating iron deficiency anaemia), whereas significantly fewer boys are affected (Bates et al. 2012; see ‘Findings of the National Diet and Nutrition Survey'). Information on iron levels in younger children is not yet available from the NDNS Rolling Programme. However, based on data from the 1997 NDNS report, the UK's SACN estimated the prevalence of low serum ferritin levels in younger children (4–6 years) to be around 3–12% (SACN 2010). SACN estimated that around 5% of 15–18 year-old girls have iron deficiency anaemia, with lower prevalence rates indicated for younger girls (1.7–2.5%) and all boys (0.6–1.2%) (SACN 2010). Iron deficiency anaemia has been shown to be particularly common in girls who have tried to lose weight and among vegetarians (Gregory et al. 2000).

Dietary solutions to low iron status include eating sources of haem iron such as lean red meat (which will provide nutrients such as zinc as well as iron), oily fish (which will also supply vitamin D and omega-3 fatty acids) and opting for iron fortified breakfast cereals. Liver is a rich source of iron and iron is also present in bread, eggs, dried fruit and pulses.

Anaemia carries implications for both mental and physical performance. Symptoms include fatigue, lassitude and breathlessness on exertion (SACN 2010). Evidence from observational studies suggests that iron deficiency anaemia is associated with poor cognition in school-aged children. However, iron deficiency anaemia is also associated with a number of socio-economic and biomedical disadvantages that can affect children's development (Falkingham et al. 2010; SACN 2010). A recent systematic review and meta-analysis of studies looking at the effects of oral iron supplementation on cognition concluded that iron supplementation improved attention and concentration in adolescents irrespective of baseline iron status, and improved intelligence quotient (IQ) in anaemic children. But the authors noted that the limited number of included studies were generally small, short and methodologically weak (Falkingham et al. 2010). SACN also reviewed the evidence from supplementation trials in children aged 3 years or older and concluded that there is evidence for a beneficial effect of iron treatment on cognitive development in anaemic children, but none of the trials reported long-term follow-up of children to determine whether any benefits were sustained (SACN 2010). EFSA concluded in its scientific opinion on iron that it is well established that inadequate dietary iron intake in humans leads to reduced oxygen transport, which could have an impact on cognitive function. EFSA concluded that a cause and effect relationship has been established between dietary intake of iron and normal cognitive function (EFSA 2009) and a health claim relating to iron and cognitive function has since been permitted by the European Commission (ec.europa.eu/nuhclaims/).

Oral health

The Office for National Statistics carried out its fourth Children's Dental Health Survey in 2003. This survey has been carried out every 10 years since 1973 and aimed to establish the state of dental health of children in the UK, and to monitor change since earlier surveys. The fifth Children's Dental Health Survey is underway and is likely to be published within the next 2 years. The surveyed population in 2003 included children aged 5, 8, 12 and 15 years attending state and independent schools. In addition to dental examinations carried out by trained staff, questionnaires were sent to parents to acquire information on children's oral hygiene and dental care, as well as barriers to dental care (Pendry et al. 2004; Lader et al. 2005). In surveys prior to 2003, dental caries was defined as obvious decay experience, being the sum of teeth with decay into dentine, filled teeth or teeth that were missing due to decay (missing primary teeth were not considered as these are unlikely to have been decayed). The criteria for assessing dental caries were changed for the 2003 survey and, in addition to the criteria mentioned earlier, also included visual caries (decay on surface and visible to the observer, but dentine not obviously cavitated). Where comparison with older data was made, the pre-2003 criteria were applied (Lader et al. 2005).

Primary (‘milk’) teeth

The proportion of children with dental caries in primary teeth decreased between 1983 and 2003 in the UK (Table 18) and, in 2003, there were differences between countries, the highest proportion being observed in Northern Ireland, followed by Wales. Five- and eight-year-old children from Wales and Northern Ireland had higher rates of decay compared with the UK average (Table 19 ). There are no separate data available for Scotland.

Table 18. Proportion of children in the UK with obvious decay (excluding visual caries) in primary teeth, by year (1983–2003)
Year/Age5 years (%)8 years (%)
Source: Lader et al. 2005.
19835070
19934561
20034357
Table 19. Proportion of children with obvious decay (including visual caries) in primary teeth in 2003, by country
Country/Age5 years (%)8 years (%)
Source: Lader et al. 2005.
England4154
Wales5271
Northern Ireland6176
United Kingdom4357
Permanent teeth

There was a clear decrease in dental caries in permanent teeth between 1983 and 2003 in all age groups (Table 20). The decrease was most pronounced between 1983 and 1993 and more prominent in permanent teeth than in primary teeth. The proportion of children with decay in permanent teeth was again highest in Northern Ireland followed by Wales, with the prevalence of decay in 8-, 12- and 15-year-olds from these countries being clearly above the UK average (Table 21).

Table 20. Proportion of children in the UK with obvious decay (excluding visual caries) in permanent teeth, by year (1983–2003)
Year/Age8 years (%)12 years (%)15 years (%)
Source: Lader et al. 2005.
1983388193
1993195263
2003143449
Table 21. Proportion of children with obvious decay (including visual caries) in permanent teeth in 2003, by country
Country/Age8 years (%)12 years (%)15 years (%)
Source: Lader et al. 2005.
England174155
Wales265465
Northern Ireland347378
United Kingdom194357

The prevalence of tooth decay was higher in schools in deprived areas compared with schools in non-deprived areas for all age groups and, in general, more teeth were affected in children from schools in deprived areas (Lader et al. 2005).

Tooth surface loss (TSL)

TSL is pathological non-carious loss of tooth tissue resulting from erosion, attrition or abrasion of the tooth enamel. This condition, unlike dental caries, is associated with consumption of acidic foods and drinks. Twenty per cent of 5-year-olds showed TSL on the buccal (outward) surfaces of primary incisors and 53% showed TSL on the lingual (inward) surfaces of the primary incisors. Among 8-year-olds, 4% showed signs of TSL on buccal and 14% on lingual surfaces of permanent incisors, and 10% had TSL on molars. The proportion of children with TSL on the permanent dentition increased with age. Among 12-year-olds, 12% had signs of TSL on buccal and 30% on lingual surfaces of permanent incisors, and 19% on molars. The respective numbers in 15-year-olds were 14% on buccal and 33% on lingual surfaces of permanent incisors, and 22% on molars (Lader et al. 2005).

Oral health and hygiene

In 2003, a third of 5-year-olds had some gum inflammation (gingivitis), compared with two-thirds of 8- and 12-year-olds. In 15-year-olds, the proportion was somewhat lower at 52%. The proportion of children with gum inflammation has increased since 1983 in all age groups, although in 15-year-olds the change was less pronounced than in other age groups. The proportion of children with dental plaque (biofilm formed by colonising bacteria) had also increased since 1983 and was highest in 8- and 12-year-olds (76 and 73%, respectively). Fifty per cent of 5-year-olds and 63% of 15-year-olds had plaque. Levels of calculus (calcified plaque) rose with age from 6% in 5-year-olds to 39% in 15-year-olds, and had increased over the previous 20 years. Children in Wales were less likely than those in England and Northern Ireland to have plaque, gum inflammation or calculus although not all differences were statistically significant (Lader et al. 2005).

Overall, more than three-quarters of children in all age groups in 2003 reported brushing their teeth at least twice a day, which was higher than 20 years previously. Between 19% and 24% of all children reported brushing once daily or less. Girls in all age groups tended to brush more frequently than boys. Generally, more frequent brushing was associated with less plaque and gingivitis, except for 8-year-old children (Lader et al. 2005).

Country-specific findings

More recent data are available for the different regions of the UK. Data from 2012 showed that, in England, 28% of 5-year-olds had experienced dental decay in primary teeth compared with 31% in 2008 (also see Tables 18 and 18 for older data). On average, the affected children had 3.38 teeth that were decayed, missing or filled (0.94 across the whole sample). Areas with poorer oral health tended to be in the north of England and in the more deprived local authorities (Davies et al. 2013). Findings from a survey in 2008/2009 showed that a third (33.4%) of children aged 12 years experienced obvious dental decay in adult teeth, with an average of 2.21 decayed teeth (missing, filled or with obvious lesions) per affected individual (0.74 on average across the whole sample) (Rooney et al. 2010).

A recent survey in Wales (2011/2012) found that 41% of 5-year-old children had experience of decay, compared with 47.6% in 2007/2008. The average number of decayed, missing or filled teeth per affected child was 3.85 (1.59 across the whole sample) (Morgan et al. 2013). A survey from 2008/2009 found that 42.5% of 12-year-olds had obvious dental decay (decayed, missing or filled), with an average of 2.3 decayed teeth among those affected (0.98 across the whole sample) (Morgan et al. 2010).

In Scotland, 33% of Primary 1 children (mean age 5.5 years) had obvious decay in their primary teeth in 2012, with a mean number of affected teeth of 4.1 in those with obvious decay (1.35 across the whole sample) (Macpherson et al. 2012). A report from 2009 found that 36.4% of Primary 7 children (mean age 11.5 years) experienced dental decay in their permanent teeth, with an average number of decayed, missing or filled teeth of 2.41 per affected individual (0.88 across the whole sample) (Merrett et al. 2009).

Diet and dental caries

Dental caries arises when several factors occur simultaneously, in particular a susceptible tooth surface, presence of acid-producing bacteria and a source of fermentable carbohydrate (e.g. sugars and starches). Hence, diet has the potential to influence dental decay. However, the most important dental health strategy is regular (at least twice daily) brushing of teeth with a fluoride-containing toothpaste. Since the introduction of water fluoridation (in some parts of the country) and recognition of the importance of fluoridation of toothpaste (introduced in the mid 1970s), dental caries prevalence has fallen, as illustrated in the previous section. Following recommendations on dental health by the Department of Health and British Association for the Study of Community Dentistry in 2007, producers of toothpaste in the UK increased the fluoride content of toothpaste, which Public Health England suggests could be partly responsible for reductions in the proportion of children affected by dental decay and its severity between 2008 and 2012 in English 5-year-olds (Davies et al. 2013). Fluoride strengthens the tooth enamel, providing resistance to decay (BNF 1999).

Sugars and other fermentable carbohydrates are fermented by bacteria on the tooth surface (typically located in dental plaque). This results in localised acid production, which in turn can lead to progressive destruction (demineralisation) of teeth, particularly if pH remains low owing to frequent ingestion of fermentable carbohydrates. Although all fermentable carbohydrates have the potential to cause dental decay, the main dietary factor is frequency of sugars consumption, this being more important than the total amount consumed. It has also been suggested that limiting sugar-containing foods and drinks as well as snack foods containing starch (e.g. crisps) to meal times is one way to reduce the incidence of caries. This influences frequency, and the saliva produced during the meal helps restore optimal pH in the mouth. Although sugars and fermentable carbohydrates have been linked to dental decay, EFSA recently concluded that available data do not allow the setting of an upper limit for intake of (added) sugars in relation to dental caries reduction. This is because caries development related to consumption of sucrose and other cariogenic carbohydrates does not only depend on the amount of sugar consumed, but is also influenced by frequency of consumption, oral hygiene, exposure to fluoride, and various other factors (EFSA 2010a). Another factor that affects the risk of developing caries is the retentiveness (stickiness) of the carbohydrate. Foods such as dried fruit or toffees may stick to teeth for a longer time than would occur with less sticky food. Therefore, it is important to brush teeth regularly.

Chewing sugar-free gum, which promotes saliva production, has been found to reduce dental caries. EFSA has accepted a health claim linking xylitol (an artificial sweetener) chewing gum/pastilles and risk reduction of dental decay, and has agreed that the wording ‘xylitol chewing gum reduces the risk of caries in children’ reflects the scientific evidence for caries reduction (EFSA 2008a).

Diet and dental erosion

Dental erosion (TSL) is the loss of hard tissue by chemical etching, without bacterial involvement. Acids responsible for erosion occur in food and drinks, which can either lead to loss of hard tissue or to softening of the enamel or dentine, making it more prone to attrition and abrasion. Softened enamel may be rehardened by minerals in saliva, and it is clear that excessive oral hygiene should be avoided after exposure to potentially erosive events. Dietary acids are present, for example, in fresh fruit and fruit juices (e.g. oranges, lemons, limes), pickles and other vinegar-containing foods and soft drinks (BNF 1999).

Bone development

Optimising bone development during childhood and adolescence is crucial in order to decrease the risk of osteoporosis later in adult life. Optimum bone development is also important for the avoidance of skeletal problems in childhood and adolescence, such as rickets in young children, which is a disease where bones are deformed owing to an insufficiency of vitamin D. Although the development of rickets typically would happen before school age, low vitamin D levels in teenage girls may increase risk of rickets in their offspring and be associated with an increased risk of osteomalacia in the girls themselves. There is a re-emergence of rickets and osteomalacia in some subgroups of the population in the UK, predominantly African-Caribbean, Middle Eastern and South Asian (SACN 2007).

Most of the skeletal mass is laid down during childhood and adolescence. It is estimated that by post-puberty (16 years onwards), approximately 80–90% of peak bone mass is achieved (Lanham-New et al. 2007). Throughout early childhood, bone mass increases linearly with skeletal growth, whereas during the pubertal years a rapid increase in bone density can be observed (by as much as 40–70%). Bone density continues to increase for several years after the cessation of growth until peak bone mass is achieved. The exact age at which this occurs remains controversial but is between 18 and 35 years of age (Lanham-New et al. 2007).

Beside genetic factors that influence peak bone mass and account for roughly 70–75% of the variance seen (Lanham-New et al. 2007), nutrition and physical activity play an important role in bone development. The main nutrients associated with bone development are calcium and vitamin D.

Calcium

Calcium is essential for bone growth as it is required for the mineralisation of bone. It is the most abundant mineral in the human body. Bones and teeth account for approximately 99% of the body's total content of calcium, where it is a main structural component (stored as hydroxyapatite) (Phillips 2004; Theobald 2005; EFSA 2008b). An adequate intake of calcium is one of a number of factors that are important for acquiring and attaining optimum peak bone mass. Diets containing insufficient calcium may lead to a low bone mineral density and contribute to impaired bone development in early life (Theobald 2005; EFSA 2008b). This may also have implications for bone health, notably risk of osteoporosis, in later life (see Theobald 2005). The daily amount of calcium deposited in the skeleton during childhood is about 150–200 mg on average. However, during times of rapid growth, for example during puberty, the total amount of calcium deposited per day is greater and peaks at around 400 mg per day (Prentice 2013). Therefore, total calcium needs are greater during adolescence than at any other time of life (see Tables 2a and 2b). There is evidence that calcium absorption adapts according to calcium intake, i.e. a larger proportion of calcium is absorbed when intakes are lower. However, this adaption comes at a price; for example, when people go from a high calcium intake to a low calcium intake, there is a period when calcium is mobilised from the skeleton and there is a loss of bone mineral (Prentice 2013).

Data from the latest NDNS report show that 18% of girls aged 11–18 years and 7% of boys of this age have intakes below the LRNI, suggesting insufficient intakes. Only 2% of girls and none of the boys in the younger age group (4–10 years) had intakes below the LRNI (Bates et al. 2012) (see section ‘Findings of the National Diet and Nutrition Survey’; Table 10).

A Cochrane review, looking at the effect of calcium supplementation (including provision in food) on bone density in healthy children, concluded that there was a small positive effect on total body bone mineral content and upper limb bone mineral density, but no effect at any other site was found. The authors suggest that the increase in bone mineral density was unlikely to result in a clinically significant decrease in fracture risk (Winzenberg et al. 2006). A subsequent review found a statistically non-significant increase in total body bone mineral content following calcium supplementation (including provision in food) in children and adolescents, which became statistically significant when the analysis was restricted to studies where baseline calcium intakes were low. The authors argue that studies where subjects have relatively high baseline calcium intakes, including in the control group, are unlikely to see a positive effect of additional calcium intake on bone mineral content (Huncharek et al. 2008). The effect of calcium supplementation on bone development remains controversial, with many experts pointing out positive effects of supplementation in various studies (Prentice et al. 2006; Lanham-New et al. 2007; Prentice 2013). Another reason for inconsistencies between studies may be the use of different forms of supplementation, i.e. calcium supplements vs. food sources of calcium. EFSA has noted that most studies are of relatively short duration and that it is currently not possible to establish whether the acceleration in bone mineral accretion during temporary supplementation would result in increased peak bone mass at maturity if the higher level of calcium intake were to be maintained (EFSA 2008b).

Calcium is present in a wide range of foods in varying amounts and the bio-availability also varies considerably. Dairy products, such as milk, yogurt and cheese, are plentiful sources of readily absorbed calcium. Fish consumed with soft edible bones (such as whitebait, canned sardines or canned salmon) also contain significant amounts of calcium, as do foods fortified with calcium (e.g. in the UK white and brown flour is fortified with calcium). Pulses, wholegrains, nuts, seeds, dried fruits and some green vegetables (e.g. broccoli, spring greens and kale) contain some calcium, although some of these foods also contain substances that bind to calcium and inhibit absorption (e.g. phytates in wholegrains and pulses, oxalate in spinach and rhubarb) (Phillips 2004; Theobald 2005). The contribution of foods to total calcium (and vitamin D) intakes in UK children is shown in Table 22 (data for 2008–11 will be published in 2014).

Table 22. Foods that contribute to calcium and vitamin D intakes in UK children
NutrientFood type
  1. *See Table 9 for data on average intakes.

Source: Gregory et al. 2000.
Calcium*Milk and milk products (47–48%); cereals and cereal products (27%); vegetables and potatoes (6–7%); meat and meat products (6%); fish and fish dishes (2%); fruits and nuts (1%)
Vitamin D*Fortified cereals and cereal products (35–37%); fat spreads (21–22%); meat and meat products (20–22%); fish and fish dishes (8–10%); eggs and egg dishes (7%); milk and milk products (2%)
Vitamin D

Vitamin D is critical for bone development and health as it is required for calcium absorption (Prentice 2013). It is also known to stimulate matrix formation and bone maturation, and enhances osteoclastic activity (osteoclasts are bone-building cells) (Lanham-New et al. 2007). It has been estimated that gut absorption of calcium is increased to 30–40% of intake with adequate vitamin D status compared with 10–15% without adequate vitamin D (Holick 2007). Others suggest that in the vitamin D replete state, calcium absorption can reach 60–80% (Pettifor & Prentice 2011). Severe vitamin D deficiency in children results in rickets (Lanham-New et al. 2007; Pettifor & Prentice 2011). There has been much controversy among experts about which cut-off levels should be used to define optimum vitamin D levels (Lanham-New et al. 2011; Prentice 2013). In recent years, a number of additional functions of vitamin D have been proposed (such as reducing susceptibility to some cancers, muscle loss, autoimmune disease and infection), over and above its role in bone health, and debate continues as to the best threshold to use as an indicator of inadequate blood levels (this is currently being considered by the UK government's advisory committee, SACN) (Prentice 2013).

Vitamin D is primarily produced in the skin in response to exposure to sunlight; the amount produced being influenced by latitude, skin pigmentation and extent of clothing. Solar UV radiation intensity varies with latitude and time of year. From mid-October to the beginning of April in the UK, UV radiation is not strong enough to stimulate vitamin D production, which means reliance on dietary vitamin D and body stores (EFSA 2008c). As a result, prevalence of low vitamin D levels is generally highest during the period of January to March (SACN 2007). Also, some ethnic groups living in the UK are particularly prone to vitamin D deficiency because of the dark pigmentation of their skin coupled with the reduced level of sun irradiation at higher latitudes, such as those characteristic of Northern Europe, as well as cultural clothing norms that limit skin exposure. Continuation of vitamin D supplementation (10 μg/d) is advised for Asian children living in the UK after the age of 5 years, particularly where religion and customs dictate that skin is kept covered when outside (see section ‘Nutritional requirements of schoolchildren’).

Data from the NDNS Rolling Programme suggest that one in five 11–18 year-old children living in the UK has inadequate blood vitamin D levels (Bates et al. 2012). Such data is not currently available from the survey for younger schoolchildren, but the previous NDNS revealed that 2–3% of 4–6 year-olds and 4–7% of 7–10 year-olds had inadequate vitamin D levels, suggesting that the prevalence of inadequate vitamin D levels increases with age during childhood (SACN 2007, 2008). The proportion of boys and girls aged 11–18 years having low vitamin D status has increased between 1997 and 2008–2011, from 10–16% to 20% (SACN 2007, 2008; Bates et al. 2012). The higher risk of vitamin D deficiency in some ethnic groups living in the UK was confirmed in a re-analysis of 1997 NDNS data, with 85% of non-White children having inadequate vitamin D levels compared with 30% of White children (Absoud et al. 2011). The higher prevalence levels compared with those levels reported earlier are due to use of a higher cut-off level to determine vitamin D inadequacy (50 nmol/L, compared with 25 nmol/L that has traditionally been used and predicts risk of rickets specifically). The cut-off level of 25 nmol/L was set to prevent the occurrence of rickets; however, some experts believe that cut-off levels should be higher because of potential additional benefits of higher vitamin D levels in relation to a number of chronic diseases, including osteoporosis, diabetes, CVD and some cancers, and for ‘optimising’ immune function (Lanham-New et al. 2011).

Time spent exercising and playing outdoors has also been associated with vitamin D status. Children who exercise and play outdoors for at least 60 minutes a day had significantly higher vitamin D levels compared with those who spend less than 30 minutes per day exercising and playing outdoors. In contrast, spending more time watching TV was associated with lower vitamin D levels (Absoud et al. 2011). There also seem to be socio-economic differences, with children from families receiving income support having significantly lower vitamin D levels (56.2 nmol/L), on average, compared with those not in receipt of benefits (62.9 nmol/L). Around half of the children from families on income support, as opposed to a third of children from families not eligible for support, have vitamin D levels below 50 nmol/L (Absoud et al. 2011).

A Cochrane review, summarising the evidence of vitamin D supplementation on bone mineral density in children, concluded that although current evidence does not support vitamin D supplementation as a means to improve bone density in healthy children with normal vitamin D levels, supplementation of deficient children may be clinically useful (Winzenberg et al. 2010).

Other dietary factors

Dietary protein intake is also important for bone development and protein–energy malnutrition can lead to skeletal problems. Positive associations between total protein intake, bone mineral content and bone size have been reported in children and adolescents (Prentice et al. 2006; Darling et al. 2009; Jesudason & Clifton 2011). However, there is some controversy about the relationship between dietary protein, in particular that derived from animal sources, and calcium metabolism. In adults, excess dietary protein can result in increased urinary calcium losses and therefore increased bone loss (Prentice et al. 2006; Lanham-New et al. 2007). More recently it has been argued that increased urinary calcium excretion associated with higher protein intakes may be a consequence of increased gut calcium absorption. It was also suggested that dietary protein is most beneficial for bone in the presence of calcium sufficiency and adequate fruit and vegetable intakes (to neutralise the acidity of the diet as a whole) (Jesudason & Clifton 2011).

Vitamin K is also important for the skeleton and deficiency of vitamin K may lead to a reduction in bone formation and decreased bone strength (Lanham-New et al. 2007). In terms of food groups, a high intake of fruit and vegetables has been found to be associated with bone development; the exact mechanisms behind this are yet to be established (Prentice et al. 2006; Lanham-New et al. 2007). High sodium intake and caffeine consumption have both been suggested to negatively influence calcium balance, although the evidence is inconsistent. There has also been concern that carbonated drinks may negatively impact on bone development because of the perception that such drinks contribute to acid load. However, purported associations between high intakes of carbonated drinks and bone development may be due to the displacement of milk from the diet rather than negative effects of carbonated drinks per se (Prentice et al. 2006).

Physical activity

Physical activity is crucial for bone development, particularly high-impact activities that include hopping, jumping and skipping, as well as weight training (Hind & Burrows 2007; Lanham-New et al. 2007). For optimal bone development, children and adolescents are advised to follow the UK guidelines for physical activity (see section ‘Physical activity’). However, while weight bearing exercise is known to have a positive effect on bone mineral density, paradoxically bone health is a cause for concern in some girls who are engaged in competitive sports, such as gymnastics or distance running, in particular when combined with low energy intakes. This may be due to the combination of intensive training and low energy intakes interfering with growth and development, and efforts to control weight in sports where minimal body fat is perceived desirable. This combination often also results in late onset of menstruation or amenorrhoea. These factors can lead to some highly trained female athletes and ballet dancers having poor bone density (Ackerman & Misra 2011). Therefore, for those who engage in competitive sports, an adequate supply of energy (as well as nutrients) is crucial.

Food allergy and intolerance

Food intolerance, which includes food allergy, is an adverse reaction to food that is reproducible and takes place every time contact is made with a particular food or ingredient. If the reaction involves the immune system, it is known as food allergy (FSA 2008; Burks et al. 2012). Non-allergic adverse reactions to food are mediated by non-immunological mechanisms, including enzyme deficiencies (e.g. lactose intolerance), pharmacological effects and other non-defined idiosyncratic responses (Buttriss 2002b; FSA 2008). Acute (rapid onset) allergic reactions to food are typically mediated by immunoglobulin (Ig) E, with symptoms usually starting within 2 hours (and sometimes within minutes) after ingestion of or exposure to the trigger food; reactions typically involve the skin, gastrointestinal tract and respiratory tract. Allergic reactions to foods can also be non-IgE-mediated immunologic reactions (e.g. cell-mediated); these include food protein-induced enterocolitis, proctocolitis and enteropathy syndromes. These latter conditions are associated with abdominal symptoms and primarily affect infants or young children. Food allergies can also involve a combination of IgE-mediated and non-IgE-mediated responses, as is the case with atopic dermatitis (Burks et al. 2012). Prior to the manifestation of an allergic reaction to a particular food, sensitisation to the food must occur. However, sensitisation does not always lead to clinical reactivity and symptoms of food allergy; so, sensitisation (presence of IgE antibodies in blood) alone is not sufficient to define food allergy (Mills et al. 2007; Burks et al. 2012). Allergic reactions to food vary considerably in their severity and the discomfort they cause, but the majority are not life-threatening. However, some reactions, known as anaphylactic reactions, can be very severe and even fatal (Buttriss 2002b; FSA 2008; Burks et al. 2012).

Although a variety of foods can trigger allergic reactions, a minority of foods cause the majority of allergic reactions, with most being attributed to the ‘major food allergens’ peanut, tree nuts, egg, milk, fish, crustacean shellfish, wheat and soya. Protein-containing food additives and colouring agents, such as annatto, carnitine and gelatin, can induce allergic reactions. Other additives such as artificial flavours (e.g. tartrazine) and preservatives (e.g. glutamates and sulphites) might cause adverse reactions, but an immune mechanism has not been identified, and such reactions are classified as intolerance (Burks et al. 2012). The amount of an allergenic food or ingredient required to provoke a reaction in a sensitive individual varies considerably from person to person and also over time, depending on a range of factors (FSA 2008). These include age and whether the food was consumed on an empty stomach, with other foods or close to exercise (Burks et al. 2012). The severity of a reaction cannot be accurately predicted by the severity of past reactions, by the serum IgE levels or the size of a skin prick test wheal (Burks et al. 2012).

Estimates of the prevalence of food allergy in the UK (and elsewhere) vary, mainly due to methodological differences. Prevalence has been suggested to be around 5–8% in children (FSA 2008; BSACI 2013) and estimates in adults vary from 1–2% (FSA 2008) to up to 4% (BSACI 2013). The prevalence in adults is lower as many children outgrow their allergies, often before they even start school. The extent of perceived food allergies and intolerances is usually considerably greater than the actual prevalence. For example, in a robust study involving almost 1000 mothers from the Isle of Wight with babies aged 3, 6, 9 and 12 months, between 2.2% and 5.5% of infants were found to respond to skin prick tests and a subsequent double-blind, placebo-controlled food challenge (only carried out in those with positive skin prick test results) during the first year of life. In contrast, 14.2% of the study population reported that their child suffered from adverse food reactions (Venter et al. 2006). Over-reporting of food allergies and intolerances often leads to an overestimation of the prevalence rates if measurements are based on self-reported data (Madsen 2005; Mills et al. 2007). A meta-analysis of studies has found that the incidence of self-reported food allergies in Europe ranges between 3% and 35%, whereas the incidence rates were lower in studies where subjects were assessed objectively for food-related sensitisation and symptoms (Asero et al. 2006).

There is a consensus among experts that the prevalence of allergic disease (which includes asthma, rhinitis and eczema) appears to have increased in the past several decades (BNF 2013), although methodological issues make interpretation of data challenging (Burks et al. 2012; Lack 2012). But the picture for food allergy specifically is less clear and the Isle of Wight Study research team has found that the rate of sensitisation to foods has not increased over the last two decades (FSA 2008). Higher hospital admission rates have been reported (Gupta et al. 2007); this may reflect an increase in the awareness of food allergies and hence in their diagnosis, but could also be a reflection of true increases in prevalence (Lack 2012).

As mentioned earlier, the majority of food-induced allergies are attributable to a minority of foods and avoiding the allergen-containing food is the only way to avoid allergic reactions.

Avoidance of food sensitisation in the first place, and therefore the subsequent risk of allergy, would be the best way to prevent food allergy-induced illness. Until recently, pregnant women with a family history of allergic disease were advised as a precautionary measure not to consume peanuts during pregnancy and lactation, but this advice has been revoked (FSA 2009). Experts now believe that eliminating potentially allergenic foods during pregnancy or lactation, and delaying introduction during weaning is not an effective measure to reduce the risk of allergy. In fact, it has been suggested that exposure via the mother and dietary introduction of allergenic foods (e.g. peanuts) as a normal part of weaning (rather than delaying introduction) might actually prevent the development of clinical allergy (Burks et al. 2012; Lack 2012), as there is some evidence that there are critical periods in early life when exposure triggers normal immune system tolerance (Du Toit et al. 2008). The theory that earlier, rather than late, introduction of foods such as peanuts can lead to tolerance and protect against the development of food allergies is currently being tested in two randomised controlled trials (Learning Early About Peanut Allergy study, Enquiring About Tolerance study; see Lack 2012).

To explore the relationship between genetic and environmental factors and the development of food allergy, 12 000 newborns and their families from nine European countries have been recruited in the EuroPrevall birth cohort study (www.europrevall.org), the aim of which was to examine regional differences in the prevalence and risk factors of food allergy in European children using gold-standard diagnostic criteria (McBridge et al. 2012). This study, and others in the area, will hopefully shed more light on the development and treatment of food allergies in children.

Cognitive function

Interest has grown in determining whether nutrition and diet influence cognitive function, and there has been particular interest in the association between diet and cognitive function in schoolchildren. Several systematic reviews have been undertaken that are discussed below.

Breakfast

In the review by Ells et al. (2008) of UK-relevant studies, commissioned by the Food Standards Agency, the largest number of publications on diet and cognitive behaviour examined the effect of breakfast. Three out of four studies on the effect of breakfast clubs in schools found a small but positive impact on a selection of educational outcomes, while one study found no effect. Four out of six studies looking at breakfast consumption vs. fasting identified some improvements in problem solving, attention and episodic memory after cereal consumption, and in complex visual display tests after consuming breakfast. Two out of six studies were unable to demonstrate any significant differences. Ells and colleagues noted that it was difficult to draw together findings from the different studies due to numerous inconsistencies between studies and the shortcomings of many studies (Ells et al. 2008).

Hoyland et al. (2009) reviewed studies in populations comparable with the UK as well as studies in low-income (developing) countries and reported that the majority of studies looking at breakfast vs. no breakfast found a positive effect on cognitive function, which they suggested was more obvious later in the mornings. Overall, studies mainly showed improvement in mathematics or arithmetic scores, which they suggested may be due to increased attendance or decreased absenteeism. Studies in developing countries found that cognitive performance following breakfast consumption was better in at-risk or undernourished children, with few if any effects in well-nourished and not-at-risk children. Evidence that one type of breakfast was substantially better than another was lacking. Studies looking at long-term effects of school breakfast programmes and breakfast clubs were mainly carried out in schools with a high proportion of children from low socio-economic backgrounds or a high proportion of undernourished and at-risk children, but benefits were no greater in or confined to undernourished or at-risk groups in most studies that also included well-nourished controls. The reviewers emphasise that, overall, the quality of studies was rather poor (Hoyland et al. 2009).

A more recent systematic review investigated the effect of breakfast on behaviour (in-class or at school) and academic performance in children (Adolphus et al. 2013). Overall the evidence suggests beneficial effects of breakfast for on-task behaviour in the classroom, mainly in younger children (<13 years). For school performance outcomes, evidence suggests a positive association between habitual breakfast frequency/quality and school grades/achievement test scores. However, the study authors highlight that research on breakfast and educational outcomes is prone to confounding, not least because breakfast levels vary by socio-economic background. Adequate control for confounders varied among the studies identified, and some studies failed to adequately adjust for SES (Adolphus et al. 2013).

Several studies in children and adolescents have considered the glycaemic index (GI) of breakfast, finding that consuming a lower GI breakfast is associated with beneficial effects on cognitive performance, including memory, attention, response time and accuracy. Beneficial effects of a low-GI compared with a high-GI breakfast or breakfast omission were mainly observed later in the morning (Ingwersen et al. 2007; Micha et al. 2010, 2011; Cooper et al. 2012). The carbohydrate in low-GI foods is thought to be released more slowly. However, a review looking at the effect of the glycaemic load (GL) of breakfast (a measure that combines both the GI and the amount of carbohydrate present) suggested that there was insufficient evidence to demonstrate a consistent directional effect of GL on short-term cognitive performance in 12-year-old children (Gilsenan et al. 2009). One subsequent study also found no effect of GL on cognitive performance but, in this study, GL was mainly reduced by lowering the carbohydrate content of the breakfast (via replacement with protein) and the authors argued that the lower carbohydrate content of the low GL breakfast may have been responsible for the lack of effect on cognitive function over 3 hours following breakfast consumption, because blood glucose concentrations fell below baseline levels within 90 minutes of eating breakfast even when it mainly comprised low-GI foods (Brindal et al. 2012). However, in another study, low GI was associated with better cognitive performance despite a lower total carbohydrate content than in the high-GI meal, in children aged 6–7 years (Benton et al. 2007).

The GI of a food or meal is influenced by various factors, including the type of carbohydrate, the degree of processing as well as the presence of other food components. Some types of fibre, mainly viscous fibres, protein and fat can reduce the GI of a food or meal. However, evidence to date suggests that more studies in this area may be warranted.

Snacking

A recent review by the British Nutrition Foundation (Miller et al. 2013) looked into the effect of snacking on cognitive function. Although there is a limited amount of research in this area, some studies hint that increased eating frequency and snacking (while still maintaining an appropriate dietary energy intake) appears to be beneficial for cognitive function (especially memory) and mood, by counteracting the decline in cognitive function sometimes experienced between meals. More research is needed to confirm these findings and to understand if the timing of intake and/or snack composition modifies any potential effects. Snacking has the potential to contribute significantly to micronutrient intakes in UK children, depending on the choice of snack. One study found that the nutrient composition of snacks in UK children aged 11–12 years was not significantly different from that of foods consumed during main meals, and snacks contributed at least 30% of the intake of a number of micronutrients, including iron, calcium, thiamin, riboflavin, folic acid, carotene (a precursor of vitamin A) and vitamin C, and also significantly contributed to fibre intake.

Omega-3 fatty acids

The systematic review by Ells et al. (2008) included five studies examining the effect of fish oil supplementation on learning and behavioural outcomes. All studies were carried out in a population aged 5–13 years with symptoms of neurodevelopmental disorders [dyspraxia and attention deficit hyperactivity disorder (ADHD)]. Two studies [using supplements rich in docosahexaenoic acid (DHA)] found small, but statistically significant, positive effects on only a few of a number of subjective parent and teacher observations (objective measures not examined). Only one study, using a supplement rich in eicosapentaenoic acid (EPA), reported significant improvements in both objective and subjective behavioural and educational outcomes. The reviewers also discussed findings published following their original systematic search that suggest that fish oil supplements may potentially improve cognitive performance (Ells et al. 2008). However, the findings of two subsequent UK studies do not support this proposition (Kennedy et al. 2009; Kirby et al. 2010). One study, giving EPA and DHA to 8–10 year-old children for 16 weeks, found very few significant differences between the supplemented and placebo groups on learning and performance measures (one being in favour of the placebo) (Kirby et al. 2010). A study using DHA for 8 weeks in 10–12 year-old children found that the treatment with two different doses (400 or 1000 mg) had no consistent or interpretable effect on performance (Kennedy et al. 2009). No health claims relating to DHA intake in children and adolescents (or adults) and cognitive function are as yet permitted in the European Union.

Vitamins and minerals

There is evidence that deficiency of some nutrients, e.g. iron deficiency anaemia (see section ‘Findings of the National Diet and Nutrition Survey’), can lead to impaired cognitive function. Vitamins and minerals suggested to be linked to cognitive processes in children are iodine, iron, zinc and vitamin B12 (Black 2003), and low magnesium levels have been reported in children with ADHD (Sinn 2008). In the systematic review by Ells et al. (2008), two studies of low-dose multivitamin/mineral supplementation over several months were included. One reported a moderate, but statistically significant, average increase in the non-verbal IQ of children, although this may have been the result of a substantial net IQ increase in just a small subsample. A study in UK children found no significant effect of supplementation on verbal and non-verbal IQ. Ells et al. (2008) conclude that these two studies alone provide insufficient evidence to draw conclusions about the effects of low-dose vitamin and mineral supplementation on the IQ score of schoolchildren (Ells et al. 2008). A subsequent systematic review and meta-analysis included 17 trials in children aged 5–16 years, where supplementation with preparations providing at least three micronutrients was given for a minimum duration of four weeks. Overall, supplementation was found to be associated with a significant increase in non-verbal intelligence and academic performance, but the observed increase was marginal and more research is needed before public health recommendations can be given (Eilander et al. 2010).

For information on eating disorders, depression and anxiety in children see Weichselbaum and Buttriss (2011).

Food provision in school

  1. Top of page
  2. Summary
  3. Introduction
  4. Nutritional requirements of schoolchildren
  5. Findings of the National Diet and Nutrition Surveys (NDNS)
  6. Nutrition and health in childhood
  7. Food provision in school
  8. Food in the curriculum
  9. Selected initiatives and organisations of relevance to child nutrition
  10. Acknowledgement
  11. Conflict of interest
  12. References

There have been major changes in the provision of food in schools over recent years, with new school food standards being introduced in all four areas of the UK. The main aim of these standards was to ensure that children receive a healthy, balanced and nutritionally adequate meal at lunchtime when in school, to provide them with the nutrients needed for healthy growth and development. For decades, school meals have been seen as a means to ensure children receive adequate nutrition (see Passmore & Harris 2004). However, evidence began to emerge that the choice of food available was resulting in many children selecting a meal of relatively low nutritional value and therefore school meals were failing to meet children's nutritional needs (Nelson et al. 2004, 2006). This, coupled with statistics showing that obesity levels were rising in all age groups and patterns of micronutrient deficiencies were common especially in older children (see sections ‘Findings of the National Diet and Nutrition Survey’ and ‘Overweight and obesity’), led the governments of all four UK countries to take action to improve food served within the school environment. With a reported 3.5 million meals being served every day in schools in England and Wales alone (LACA 2004), this action was urgently needed.

Nutritional guidelines for school meals, produced in 1992 by the Caroline Walker Trust (CWT) (CWT 1992), have been used as a reference tool for the development of many of the school meal standards in use today. School food standards in place throughout the UK are compulsory and comprise nutrient-based standards as well as food-based standards that are compatible with the government's eatwell plate (see Fig. 13).

figure

Figure 13. The eatwell plate.

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In order to promote a consistent message about healthy eating to children, in most parts of the UK school food guidelines extend beyond school lunches to cover other food served throughout the school day (see Table 23). Nutrient-based standards are compulsory only for school lunches, and compulsory food-based standards cover not only school lunches but also food available from tuck-shops, vending machines, breakfast clubs, mid-morning/afternoon catering, and after-school clubs.

Table 23. A comparison of school meal standards and schemes in the four UK areas
 EnglandNorthern IrelandScotlandWales
Are school food standards in existence?YesYesYesYes – new draft standards came into force in September 2013
Do these comprise?Nutrient-based standards for school lunch?YesNoYesYes
Food-based standards for food other than school lunch?YesYes. Separate guidance for breakfast provided at school is available, although not mandatory.YesYes, new draft standards came into force in September 2013. These include separate standards for breakfast provided at schools.
Are these standards compulsory?Yes – standards apply to all local authority maintained primary, secondary, special and boarding schools and pupil referral units. However, they are NOT mandatory in academies, which now represent over half of secondary schools.Yes – standards apply to all grant-aided nursery, primary and post-primary schools.Yes – all grant-aided nursery, primary and post-primary schools.Yes – apply to all local authorities and governing bodies that maintain nurseries, primary and secondary schools, special schools and pupil referral units.
Free-fruit scheme?Yes, all 4–6 year-olds receive a free piece of fruit or a free portion of vegetables daily.No national programme, however a variety of initiatives exist.No national scheme currently in existence, instead it is up to local authorities to decide if pupils should receive free fruit.No national programme exists.

School food standards across the UK

England

A school meals review panel was set up in 2005 by the Department for Education and Skills to review and develop nutrition-related standards for school meals. Its report Turning the Tables: Transforming School Food (SMRP 2005) called for radical changes to school meals, which included restricting foods high in total and saturated fatty acids, sugars and salt, as well as foods made with poor quality meat. The Panel's recommendations formed the basis of new school standards for all food served within English schools, which were launched in three parts. Firstly, interim food-based standards for school lunches came into force in September 2006, followed by food-based standards for school food other than school lunches in September 2007. Finally, nutrient-based standards for school lunches were developed, which were required by law to be implemented in all primary schools by September 2008, and all secondary schools, special schools and Pupil Referral Units by September 2009. When the nutrient-based standards became law, the interim food-based standards for school lunches were replaced with the final food-based standards, whereas the food-based standards for school food other than lunches remained the same. All standards are legal requirements and apply to all local authority maintained primary, secondary, special and boarding schools and Pupil Referral Units in England (SFT 2008a). The School Food Regulations detail all of these standards (DCSF 2008); minor modifications were introduced in 2011, mainly clarifying ambiguities relating to food provision (allowing confectionery to be provided to pupils in boarding schools) and specifically exempting academies from the standards (DoE 2011).

Food-based standards (see Table 24) apply to all school lunch services, including hot, cold and packed lunch services provided on a school day. The food-based standards for school food other than lunch apply to all food provision (except lunch) up to 6 pm, including breakfast clubs, mid-morning break services, vending machines, tuck-shops, and after-school snacks and meals.

Table 24. Summary of food-based standards for school lunches and school food other than lunches in EnglandThumbnail image of

The food-based standards can help increase intakes of fruit, vegetables and oily fish, but they may not be sufficiently comprehensive to impact on intakes of fat, salt and sugar. The nutrient-based standards were set in parallel to increase the vitamin and mineral content of school lunches, and to decrease contents of fat, saturated fatty acids, NMES and sodium. Standards for the contribution of macronutrients to energy intake from school lunches (Table 25), and maximum and minimum levels for absolute amounts of macronutrients and micronutrients (Table 26) were put in place. The percentage contributions of macronutrients to energy from school lunches are the same as recommended for total energy intake throughout the day (see section ‘Nutritional requirements of schoolchildren’). Maximum levels were set for sodium, NMES, fat and saturated fatty acids, and minimum levels were set for carbohydrate, protein, fibre, vitamin A, vitamin C, folate, calcium, iron and zinc. The standard for energy is based on an average value, rather than a minimum or a maximum value (Table 26). The standards are different for primary and secondary schools, reflecting different nutritional needs at different stages of development (SFT 2008a). The standards are designed to be achieved across the food offered at lunch time within a school rather than meals consumed by individual children.

Table 25. Standards for contribution of macronutrients to energy from school lunches in England
  1. RNI, reference nutrient intake.

Source: SFT 2008a.
Not less than 50% from carbohydratePredominantly starch and intrinsic/milk sugars
Not more than 11% from non-milk extrinsic sugars
Not more than 35% from fatPredominantly unsaturated fatty acids
Not more than 11% from saturated fatty acids
Protein 30% of RNI 
Table 26. Minimum and maximum levels of nutrients in school lunches in England
NutrientMinimum or maximumPrimarySecondary
  1. NMES, non-milk extrinsic sugars.

  2. *Bracketed figure is the 5% tolerance.

Source: SFT 2008a.
Energy (kJ)2215 ± 5% (111)*2700 ± 5% (135)*
(kcal)530 ± 5% (26.5)*646 ± 5% (32.3)*
Carbohydrate (g)Min70.686.1
NMES (g)Max15.518.9
Fat (g)Max20.625.1
Saturated fatty acids (g)Max6.57.9
Protein (g)Min7.513.3
Fibre (g)Min4.25.2
Sodium (mg)Max499.0714.0
Vitamin A (μg)Min175245.0
Vitamin C (mg)Min10.514.0
Folate (μg)Min53.070.0
Calcium (mg)Min193.0350.0
Iron (mg)Min3.05.2
Zinc (mg)Min2.53.3

In England, the School Food Plan (www.schoolfoodplan.com; Dimbleby & Vincent 2013), has called for a review and simplification of the school foods standards, proposing that the nutrient standards should be abandoned and the food-based standards strengthened. A review is currently underway and a consultation is expected in early 2014.There were also recommendations about free school meal provision that are mentioned later.

Scotland

Scotland led the way in the UK in terms of transforming school food. Hungry for Success (2002), the report of Scotland's Executive Panel on School Meals, set out a whole school approach to school meals, based around the introduction of nutrient-based standards for school meals, with which all state funded schools were recommended to comply. Adoption of these standards was recommended in all special and primary schools in Scotland by 2004 and in all secondary schools by 2006 (EPSM 2002). The Schools (Health Promotion and Nutrition) (Scotland) Act 2007 (SG 2007) builds on the success of Hungry for Success and, together with provision of the Nutritional Requirements for Food and Drink in Schools (Scotland) Regulations 2008 (SG 2008b), forms part of a wider health promoting schools approach. The Regulations comprise (1) nutrient standards for school lunches; (2) food and drink standards for school lunches; and (3) food and drink standards for school food and drinks other than school lunch, such as via breakfast clubs, tuck-shops, vending machines, mid-morning services, community cafes and after-school clubs. The Regulations apply to local authority schools, grant-aided schools and hostels for pupils maintained by a local authority. The Regulations came into effect in August 2008 for primary schools and in August 2009 for secondary schools. The nutrient-based standards comprise minimum and maximum levels for the same nutrients included in the English standards: minimum levels were set for protein, carbohydrate, fibre, iron, calcium, vitamin A, vitamin C, folate and zinc; maximum levels were set for total fat, saturated fatty acids, NMES and sodium (SG 2008a).

A summary of the food standards for school lunches in Scotland is presented in Table 27; these differ slightly from the English standards. Separate drink standards for schools are included in the Regulations. These, together with food and nutrient standards, can be found in the Healthy Eating in Schools guide from the Scottish Government, which aimed to support schools in implementing the Regulations (SG 2008a). A supplementary guide for children and young people was published in 2010 (SG 2010).

Table 27. Summary of food standards for school lunches in Scotland
Source: SG 2008a.
Fruit and vegetablesA choice of at least two types of vegetable and two types of fruit (not including fruit juice) must be provided every day as part of the school lunch.
Oily fishOily fish must be provided at least once every three weeks.
Variety of extra breadAdditional bread must be provided every day as a meal accompaniment, with a variety of bread, which must include brown or wholemeal, being provided over the week.
Oils and spreadsOnly oils and spreads high in polyunsaturated and/or monounsaturated fatty acids can be used in food preparation.
Deep-fried foodsMenus must not contain more than three deep-fried items in a single week.
Chips, if served, must be served as part of a meal.
Table salt and other condimentsAdditional salt cannot be provided.
Condiments must be dispensed in no more than 10 ml portions.
ConfectioneryNo confectionery can be provided.
Savoury snacksNo savoury snacks can be provided except savoury crackers, oatcakes or breadsticks.
Other snacksNuts and seeds with no added salt, sugar or fat, can be served. Plain popcorn and fruit and vegetable snacks can be served provided they have no added salt or sugar.

Evaluations of implementation of the standards are carried out as part of Education Scotland's inspection activities. In a proportion of inspections, a Health and Nutrition Inspector evaluates the school's progress in implementing the standards (Adamson et al. 2013).

Wales

Within Wales, the Education (Nutritional Standards for School Lunches) (Wales) Regulations 2001 have provided a set of minimum standards with which school lunches must comply (WAG 2003). In a bid to further improve food and drink served throughout the school day, Appetite for Life, produced in 2006 by the Food in Schools Working Group set up by the Welsh Government, set out strategic directions and actions required to improve the quality of school lunches in Wales (WAG 2008b). This included the setting of more stringent food- and nutrient-based standards for school lunches.

In August 2013, the Minister for Education and Skills announced the introduction in September 2013 of new draft regulations [Healthy Eating in Schools (Nutritional Standards and Requirements) (Wales) Regulations], which set out the types of food and drink that can and cannot be provided during the school day and define the nutritional standards for school lunches. They apply to all local authorities and governing bodies that maintain nurseries, primary and secondary schools, special schools and pupil referral units. The standards in the draft regulations are based on existing Welsh government-recommended standards. The new regulations replace the Education (Nutritional Standards for School Lunches) (Wales) Regulations 2001. Unique to Wales, the new regulations outline separate standards for breakfast provided at school. Breakfast may only contain foods from the following categories: milk-based drinks or yoghurts; cereals, not coated or flavoured either alone or in combination with sugar or chocolate or cocoa powder; fruit; breads. Milk-based drinks provided must comply with separate drink standards outlined in the draft regulations. The draft standards for school lunches are presented in Table 28. The draft regulations also contain nutrient-based standards and food-based standards for food provided outside lunch and breakfast. For more details, see Welsh Government (WG 2013).

Table 28. Summary of food standards for school lunches in WalesThumbnail image of
Northern Ireland

Following a pilot in 2004/2005, nutritional standards for school lunches were introduced and made compulsory from September 2007 (School Food Top Marks 2009a). In April 2008, the nutritional standards were extended to include all other food and drinks provided in school, such as via breakfast clubs, tuck-shops and vending machines (School Food Top Marks 2009b). The nutritional standards are food-based and are similar to those in other UK countries and aim to ensure that more fruit and vegetables are available in schools, and that fresh free drinking water is available. Furthermore, many high fat, high sugar or salted snacks have been replaced with healthier options such as fruit, bread-based snacks, milk and water. Nutrient-based standards for school lunches were not set in Northern Ireland. For more details see School Food Top Marks (2009a,b).

Impact of school food standards

In England, net take-up of school lunches increased between 2008–2009 and 2011–2012 in primary schools (from 39.3% to 46.3%) and secondary schools (from 35.0% to 39.8%) (Adamson et al. 2013). The School Food Trust (now Children's Food Trust) carried out national surveys of primary and secondary schools in England to assess the impact of the standards on catering provision and pupil food selection and consumption (SFT 2012a, 2012b). Compared with 2005, caterers in primary schools provided a more healthy lunch, including more vegetables and salad, starchy foods not cooked in fat (e.g. pasta and rice), fruit, fruit juice, and fruit-based desserts. Fewer desserts without fruit, chips and other starchy foods cooked in fat, and no crisps or confectionery were provided. By limiting the range of foods to healthier options, in 2009 primary school pupils were having healthier lunches. The average meal taken contained over two portions of fruit and vegetables, and was lower in fat, sugar and salt (SFT 2012a).

Fat provided about 29% of lunchtime energy (well below the 35% maximum allowed), and saturated fatty acids provided around 11%, meeting the target. Overall, several positive changes in nutrient intake from school lunch were observed between 2005 and 2009 (see Fig. 14). The average sodium content of a meal had dropped by almost one-third (SFT 2012a) and this was reflected in overall sodium content of the diet (Adamson et al. 2011; see more details further down).

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Figure 14. Percentage mean difference in the nutrient content of an average meal as eaten in primary schools in England, 2009 compared with 2005.

NMES, non-milk extrinsic sugars; SFA, saturated fatty acids.

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In secondary schools, catering provision at lunchtime in 2011 was also healthier than it was in 2004, but to a lesser extent than in primary schools. Foods and drinks promoted by the new standards were offered more regularly in 2011 than in 2004, such as water, fruit juices, other compliant drinks, vegetables and salad, and starchy foods not cooked in oil. Foods with less healthy nutrient profiles, such as starchy foods cooked in oil, non-permitted drinks, condiments, confectionery and non-permitted snacks, were offered far less regularly.

The impact of these changes was reflected in pupils' food and drink choices at lunchtime. The proportion of pupils selecting starchy foods not cooked in oil increased from 15% to 27%, and twice as many children selected vegetables and salad although the proportion was still low (12% compared with only 6% in 2004). The number of pupils selecting starchy foods cooked in oil fell from 50% to 17%. As a direct consequence of certain foods that are high in fat and/or sugar not being provided at lunch time, the percentage of pupils accessing non-permitted items fell for drinks from 45% in 2004 to 5% in 2011, for confectionery from 5% to less than 1%, and for non-permitted snacks (e.g. crisps) from 11% to less than 1% (SFT 2012b).

Overall, compared with 2004, meals eaten in 2011 had a better nutrient profile (see Fig. 15). The contribution of carbohydrate, fat and saturated fatty acids to total energy intake was within the recommended range. However, although most changes were in the desired direction, vitamin C and calcium fell slightly and iron intake by almost 10% in primary school children and zinc, iron, vitamin C and folate all fell in secondary school lunches. These changes need to be considered in the context of the micronutrient shortfalls already identified in the overall diets of school children (see section ‘Findings of the National Diet and Nutrition Survey’).

figure

Figure 15. Percentage mean difference in the nutrient content of an average meal as eaten in secondary schools in England, 2011 compared with 2004.

NMES, non-milk extrinsic sugars; SFA, saturated fatty acids.

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A study commissioned by the Public Health Research Consortium (England) found that healthier school lunches not only improved nutrient intake at lunch time, but that these were also associated with improvements in the overall diet of schoolchildren aged 4–7 years. Between 2003/2004 and 2008/2009 there was a significant decrease in mean daily energy intake and percentage energy derived from fat, saturated fatty acids and NMES in children aged 4–7 years. There were significant increases in intake of protein and NSP fibre, as well as vitamin C and vitamin A, whereas total intakes of calcium, iron and zinc did not change. Sodium intakes decreased significantly between 2003/2004 and 2008/2009, from 2.0 g sodium/day to 1.85 g/day. In 11–12 year-olds, intakes of energy and percentage energy from fat also decreased, but there were no significant changes in the contribution of saturated fatty acids or non-milk extrinsic sugar to total energy. However, there were significant decreases in absolute intake of saturated fatty acids and NMES, reflecting the lower energy intakes in 2009/2010 compared with 1999/2000. There was a significant decrease in intake of sodium from 2.59 to 2.15 g/day. Intakes of calcium, zinc, vitamin C and vitamin A significantly increased, whereas mean intakes of iron and folate fell between 1999 and 2010 (Adamson et al. 2011), which is not desirable.

The study also found that there were significant improvements in nutrient content of the packed lunches of 4–7 year-old children, but that the extent of change was less than with school lunches. In 11–12 year-old children there were improvements in average content of dietary fibre, calcium, vitamin C and vitamin A in packed lunches (which were not observed in school lunches) but, unlike school lunches, improvements did not include the percentage of energy from fat and saturates or the sodium content. The researchers found limited evidence of an effect of school lunch type on the total diet of 11–12 year-olds (Adamson et al. 2011).

Of note, earlier standards introduced in England in 2001, which promoted healthy options but did not restrict less healthy items and were only applicable at lunch time, were not effective in significantly improving the diet of schoolchildren (Adamson et al. 2013).

Overall, school food programmes seem to positively influence the nutrient composition of and nutrient intake from school lunches, and also seem to have a positive influence on overall nutrient intake, mainly in younger children.

Free school meals

Providing free school meals to children from low-income families is an important public health measure. Children from all areas of the UK are eligible for free school lunches if their parents receive various forms of assistance, including Income Support, Income-related Jobseekers Allowance and support under Part VI of the Immigration and Asylum Act 1999 (for full information see www.Direct.gov.uk). It has been estimated that about 1.8 million children and young people are entitled to free school meals, but that approximately one in five children fail to take up this provision in primary schools and about a quarter in secondary schools (LACA 2004). One commonly cited reason for this is the perceived stigma associated with receiving free school meals, which prevents parents signing up for free meals, as well as eligible children taking up their entitlement (Harper & Wood 2009).

The School Food Plan (England) called for government to embark upon a phased roll out of free school meals for all children in primary schools, beginning with local authorities with the highest percentage of pupils eligible for free school meals. In September 2013, the government announced that from September 2014, all children in the first 3 years of primary school will be eligible to have a hot, free school meal, adding 1.5 million children to the current 400 000 children aged 5–7 years who are eligible for free school meals and not restricting the provision to families on low income (thus removing any stigma associated with the provision).

Packed lunches

Uptake of school meals in England during 2011/2012 was around 46% in primary schools and 40% in secondary schools (Adamson et al. 2013), with the vast majority of the remainder bringing a packed lunch (SFT 2012a). In contrast to lunch and other food provided by schools, for which clear guidelines exist, there are no official guidelines for packed lunches brought to school from home. While some primary schools have introduced packed lunch policies to support healthier eating and offer clear guidance and an opportunity to improve food consumed by all pupils, according to the School Food Trust there is little evidence of their effectiveness (SFT 2012a). The Children's Food Trust and the British Nutrition Foundation both provide tips for healthy school lunch boxes on their websites (www.childrensfoodtrust.org.uk/parents/schoolfood/packed-lunches and www.nutrition.org.uk/healthyliving/healthyeating/healthy-packed-lunches).

The Primary School Food Survey in 2009 found that healthier food and drink items were chosen and eaten more frequently by pupils taking a school lunch compared with those bringing a packed lunch, and packed lunches often included items now restricted in school lunches (SFT 2012a). Two-thirds of pupils taking school lunches took servings of vegetables and salad compared with only 8% of pupils bringing packed lunches. Similar trends were seen for water. Far fewer pupils eating school lunches ate confectionery or non-permitted drinks and snacks. Average nutrient intakes from school lunches (as eaten) were more often in line with healthy eating recommendations than intakes from packed lunches. On average, packed lunches contained more carbohydrate, NMES, fat, saturated fatty acids, vitamin C, sodium and calcium, and less protein, fibre and zinc compared with the average school lunch (Pearce et al. 2011; SFT 2012a). Similar differences between school meals and packed lunches were also found in the Secondary School Food Survey in 2011. School meals generally had a smaller percentage of energy coming from fat and saturates, contained less sodium, and provided significantly more fibre, vitamin A, vitamin C, folate, calcium, iron and zinc (SFT 2012b). These findings differ in some respects from the survey commissioned by the Public Health Research Consortium referred to earlier. In the latter survey, although there were significant improvements in the nutrient content of both school lunches and packed lunches in 4–7 year-olds and the extent of change was greater in school lunches, in 11–12 year-old children there were increases in average content of dietary fibre, calcium, vitamin C and vitamin A in packed lunches which were not observed in school lunches (Adamson et al. 2011). On average, packed lunches provided higher levels of these nutrients, as well as iron and folate (there was a fall in iron and folate in school lunches).

The Secondary School Food Survey 2011 found that a significantly greater proportion of pupils who had a school lunch had fruit (including juice) or vegetables or both as part of their meal (72%) compared with pupils eating a packed lunch (56%). This is mainly due to higher intakes of vegetables, baked beans and other pulses, and fruit juice in those eating school lunch. The proportion of children eating fruit or fruit-based desserts (excluding juice) was higher in those eating a packed lunch (SFT 2012b).

Using the findings of a meta-analysis (Evans et al. 2010a), a randomised intervention trial (‘SMART’) was conducted in children aged 8–9 years, designed to improve the food and nutrient content of packed lunches. Intervention group members received a SMART lunch box (two plastic food boxes and a lunch box cooler bag) and supporting materials, including wall charts with ideas for packed lunches, weekly menus, reward stickers and information leaflets on how to encourage children to eat more healthily. The control group received only a simple one-page leaflet on how to improve children's packed lunches. The results showed that, in the intervention group, moderately higher weights of fruit, vegetables, dairy and starchy foods and lower weights of savoury snacks were provided in packed lunches, which also provided slightly higher levels of vitamin A and folate. Levels of fats, sugars and sodium did not improve, and despite an emphasis on starchy foods and drinking water, the weight of sandwiches and sweetened drinks did not change (Evans et al. 2010b).

Schemes encouraging fruit and vegetable consumption

Although there are clear public health messages throughout the UK encouraging the consumption of fruits and vegetables, research consistently shows that children do not eat enough of these foods, with the latest NDNS reporting that 11–18 year-olds eat on average only three of the five recommended portions (comparable information is not available for younger children because there is no set definition of what constitutes a portion of fruit or vegetables for young children) (Bates et al. 2012). Providing free fruit to schoolchildren is seen as a way to tackle health inequalities and to help ensure all children get a healthy start in life. However, the provision of free fruit in schools is highly variable across the UK and mainly restricted to younger age groups.

Within England, 4–6 year-old children who attend a Local Education Authority maintained infant, primary or special school are eligible to receive a free piece of fruit or free vegetables each school day (DH 2010). While participation in the School Fruit and Vegetable Scheme (SFVS) is voluntary, schools are encouraged to participate. The most recent evaluation of the scheme found that children receiving the SFVS ate more fruit and vegetables in 2008 compared with 2004 when the scheme was initiated, although changes may partly be explained by the introduction of school food standards. It was suggested that effects of the intervention do not carry over into the home environment (Teeman et al. 2010).

While Wales does not have a national fruit and vegetable scheme in schools, programmes such as the Fruit Tuck Shop initiative encourage pupils, parents and staff to set up fruit tuck-shops in schools to provide fresh fruit, dried fruit or fruit juice to schoolchildren throughout the school day (PANNW 2009). A study evaluating the impact of the Fruit Tuck Shop initiative in schools in deprived areas found that, in isolation, fruit tuck-shops were not effective in changing children's snacking behaviour in school, but that fruit tuck-shops had a greater impact when reinforced by school policies restricting the types of foods students were allowed to bring to school (Moore & Tapper 2008).

Schools in Northern Ireland have been able to select from a variety of initiatives that focus on healthy snacking during break time ([HPA(NI) 2008]. Recent examples include the Boost Better Breaks award and the Smart Snack award, both of which state that for schools to gain membership they must only offer milk (and/or water) and fresh fruit and vegetables at break times. Information about these and other schemes in Northern Ireland can be found in the Learning to Eat Well report.

Within Scotland, a free fruit scheme was in existence across all publicly funded schools between 2003 and 2006, and formed part of the Scottish Executive's Health Improvement Programme. As part of this scheme, all aged 4–7 years received free fruit 3 times per week. This scheme has now ended, but The Schools (Health Promotion and Nutrition) (Scotland) Act 2007 gives local authorities the power to decide whether they choose to provide free fruit during the school day (SG 2007). An evaluation of the original scheme, published in 2005, found that authority professionals and school staff members perceived that the initiative had been very successful. For example, 90% of school respondents thought that the initiative had brought about an improvement in general eating habits and almost 60% perceived that pupils were consuming more fruit and vegetables as part of their school meals (MacGregor & Sheehy 2005).

Breakfast provision in schools

There has been a trend over recent years for schools to introduce breakfast clubs, particularly in primary schools. This has been driven by concerns that a substantial proportion of pupils are not eating breakfast and arrive at school hungry, which may impact negatively on school performance (see section ‘Cognitive performance’). In addition to the provision of food, breakfast clubs can also help develop social skills and provide an opportunity for additional learning through ‘play’ activities, or provide time to complete homework.

In 2008, the Welsh Government made a commitment to provide a free, healthy breakfast each day for all children of primary school age registered in maintained primary schools in Wales, if required (WAG 2008b). The initiative is intended to help improve the health and concentration of children, to assist in raising standards of learning and attainment. The provision of free breakfasts is optional, i.e. schools can choose whether or not they commit to the free breakfast programme. Breakfast provided in Welsh schools now has to comply with the new standards outlined earlier.

Breakfasts (sometimes free to all, sometimes free to those entitled to free school meals) are also provided in many schools throughout England, through breakfast clubs, but provision is not mandatory and formal standards do not exist. The Department for Education has committed to providing £3.15 million over the next two years (as matched funding) to increase healthy breakfast provision for children who are arriving at school hungry, as outlined in the School Food Plan published in July 2013 (Dimbleby & Vincent 2013). The funding will be directed to the ‘poorest’ schools (those with at least 40% entitlement to free school meals). Breakfast clubs are also in existence in schools throughout Scotland and Northern Ireland, but again are not mandatory.

Eating breakfast has been associated with positive effects on cognitive performance, on-task behaviour and academic performance (see section on ‘Cognitive function’ for more details). The School Food Trust carried out a study looking at the potential benefits of breakfast clubs, comparing 13 primary schools with breakfast clubs to nine schools without, all located in deprived areas of London. One year after introduction, average Key Stage 2 results were statistically significantly higher by 0.72 points in the schools with breakfast clubs compared with a non-significant 0.27 point increase in the schools without breakfast clubs. This difference was sustained over the next few years with no further increases. Schools believed that they had reaped significant benefit through the introduction of breakfast clubs, especially in the case of the most socially deprived. The benefits included improvement in social skills, in punctuality of children who were frequently late and in children's health and concentration levels (SFT 2008b). A recent review on breakfast clubs concluded that there are benefits to mental performance and social development, although it is unclear whether such benefits are derived from the consumption of breakfast per se, the environment or a combination of the two. The authors also suggest that benefits of breakfast clubs are more pronounced in deprived areas (Defeyter et al. 2010).

Food in the curriculum

  1. Top of page
  2. Summary
  3. Introduction
  4. Nutritional requirements of schoolchildren
  5. Findings of the National Diet and Nutrition Surveys (NDNS)
  6. Nutrition and health in childhood
  7. Food provision in school
  8. Food in the curriculum
  9. Selected initiatives and organisations of relevance to child nutrition
  10. Acknowledgement
  11. Conflict of interest
  12. References

The School Food Plan emphasises that a whole school approach is required to effectively and sustainably change eating habits of schoolchildren. In addition to school food standards, which ensure that healthy food is provided at schools, schoolchildren also need to be equipped with the skills they need to feed themselves as they move into adulthood. Therefore, it is important that children learn about the importance of healthy eating, develop an understanding of where food comes from and know how to prepare healthy meals (see Dimbleby & Vincent 2013), making nutrition an important part of the school curriculum. The UK comprises four countries, each of which has its own curriculum.

England

New primary and secondary curricula, ready for teaching from September 2014, are now finalised (www.gov.uk/government/organisations/department-for-education/series/national-curriculum). (Until September 2014, schools should follow the existing curriculum in place (www.gov.uk/national-curriculum).

Currently, food is taught as a compulsory part of the curriculum in primary schools (5–11 years) – mainly through the subjects of Design and Technology (D&T); Science; and Personal, Social and Health Education (PSHE). Each of these three subject areas specifically highlights aspects of food education for children. Combined, they provide opportunities for children to learn how to cook, understand and apply healthy eating messages and learn about the underpinning scientific principles of food science and food safety.

In secondary schools, food is taught mainly through D&T: food. Within this subject, pupils learn about healthy eating, ingredients, equipment and cooking. Nutrition and digestion are also taught in Science, and theoretical aspects of healthy eating and general health are built into PSHE. Food education aspects are emphasised in D&T, with specific references being made to cooking, healthy eating, food safety and nutritional needs.

From September 2014, cooking and nutrition will be a compulsory addition to the D&T curriculum. As part of their work with food, students will be taught how to cook and apply the principles of nutrition and healthy eating. In addition, students will be taught about where their food comes from, seasonality and the characteristics of a range of ingredients (www.gov.uk/government/organisations/department-for-education/series/national-curriculum).

Northern Ireland

The primary curriculum in Northern Ireland is set out in six areas of learning, with aspects of food being taught through different areas in a multi-disciplinary fashion. Food education is supported in primary schools (ages 5–11 years) through the subjects of The World Around Us (Science and Technology, Geography) and Personal Development and Mutual Understanding. In Northern Ireland references to specific understanding or practical cooking activities are not generally highlighted. However, guidance documents are available to help teachers plan appropriate activities for the children they teach.

At secondary school, food is taught through three main areas of learning: Learning for Life at Work (Home Economics); Science and Technology (Science); and Learning for Life and Work (Personal Development). Home economics is compulsory for all secondary school-aged pupils (ages 11–14 years), and is taught through three themes: Healthy Eating, Home and Family Life, and Independent Living. The concept is to help all young people learn practical skills in food safety and preparation, as well as the opportunity to explore real issues that they may face as family members, citizens and consumers. It is hoped that this approach will help support them for future independent living. The primary and secondary curricula are available at www.nicurriculum.org.uk.

Scotland

The curriculum in Scotland has been through a comprehensive review, with Curriculum for Excellence being published in 2009 (www.educationscotland.gov.uk/thecurriculum). The curriculum, for children aged from 3–18 years, shows the progression for different aspects of food education, known as lines of development. Food aspects are most explicitly highlighted for teaching through three of the curriculum areas: Health and wellbeing; Sciences; and Technologies. However, with a strong emphasis on interdisciplinary (cross-curricular) learning, links can be made (and are actively encouraged) with other curriculum areas. The curriculum clearly highlights food education learning, for both primary and secondary schools – all of which is statutory. For example, health and wellbeing includes the study of energy and energy balance (physical activity and health), as well as nutrition, safe and hygienic practices, and food and the consumer (food and health). In Sciences there are links to Body systems and cells (biological systems), and to the properties and uses of substances (materials). Lastly, Technologies provides the food contexts for developing technological skills and understanding.

Wales

The curriculum in Wales (http://learning.wales.gov.uk/improvementareas/curriculum/?lang=en), which was updated in 2008, ensures that children in primary and secondary schools experience learning about food. The three areas of the curriculum where food is mainly featured are: D&T: food; Science; and Personal and Social Education. The area where most children learn about food, particularly undertaking and linking practical cooking work to elements of nutrition, is D&T: food. This is a compulsory component of the curriculum, for children aged 7–14 years, covering aspects of cooking skills, food safety and hygiene, and application of healthy eating, as well as considering issues surrounding sustainability and the science behind food.

Supporting the curriculum

The British Nutrition Foundation runs an education programme for UK schools, entitled Food – a fact of life (FFL), which provides a range of free resources. Its aim is to provide educators with up-to-date, curriculum-compliant resources and training to support the rapidly changing needs of the 21st century learner. In 2013, the FFL website (www.foodafactoflife.org.uk) received over one million visits. FFL provides teachers with a comprehensive collection of resources to support the education of children and young people aged 3–18 years. Broadly, it provides information in the following topic areas: healthy eating; diet and health; cooking; food safety; and farming. FFL supports the curricula throughout the UK and has been developed to provide a progressive framework to support and inspire all those involved in food and nutrition education. In addition, continuing professional development for teachers is also offered.

Except for a small range of printed posters about nutrients and cooking, the resources are available in a range of digital formats. These include lesson ideas, worksheets, videos, podcasts, excel templates, differentiated online tutorials, recipes, interactive whiteboard activities, PowerPoint presentations and information pages. A series of eSeminars is also provided for students and teachers.

Selected initiatives and organisations of relevance to child nutrition

  1. Top of page
  2. Summary
  3. Introduction
  4. Nutritional requirements of schoolchildren
  5. Findings of the National Diet and Nutrition Surveys (NDNS)
  6. Nutrition and health in childhood
  7. Food provision in school
  8. Food in the curriculum
  9. Selected initiatives and organisations of relevance to child nutrition
  10. Acknowledgement
  11. Conflict of interest
  12. References

A large variety of initiatives and organisations exist that aim to improve the diets of schoolchildren. This section is by no means an exhaustive list.

Organisations and networks

British Nutrition Foundation and Food – a fact of life (FFL)

The British Nutrition Foundation is a charity that interprets and communicates nutrition science, making nutrition science accessible to all. The FFL programme is the Foundation's education programme, www.foodafactoflife.org.uk, see section ‘Supporting the curriculum’ for details.

Children's Food Trust and Let's Get Cooking

Formerly known as the School Food Trust, the Trust was established in 2005 and became a registered charity in 2006. It provides specialist advice, training and support to anyone who provides food for children and runs Let's Get Cooking – initially a programme to develop, establish and sustain after-school cooking clubs.

Food for Life Partnership

The Food for Life Partnership is a network of schools and communities across England committed to transforming food culture. The aim was to reach out through schools to give communities access to seasonal, local and organic food, and to the skills they need to cook and grow fresh food. Schools work towards achieving awards, based on their whole school approach. The programme is lottery funded.

Chefs Adopt a School

Chefs Adopt a School is a national charity, which sends chefs into schools to deliver food education to children about where food comes from and how it is grown, through to how to cook it. The programme covers taste, healthy eating, nutrition and hygiene as well as the recently added Front of House session.

Jamie Oliver Foundation

This is an educational charity that aimed to share a love of food and keep cooking skills alive. It interacts with primary and secondary schools across the UK to bring food to life, working to reconnect children with what food is, where it comes from and how it affects their bodies. With primary schools the theme is ‘grow it, cook it, love it’ and in secondary schools the focus is home cooking skills (www.jamieoliver.com/kitchen-garden-project/; www.jamieshomecookingskills.com).

Magic Breakfast

Magic Breakfast is a UK-registered charity dedicated to ensuring every child starts the school day with the right breakfast as fuel for learning. It delivers free, healthy breakfast foods to UK primary schools with more than 40% of pupils eligible for free school meals.

Other initiatives, resources and projects

Change4Life

Change4Life is a government-funded society-wide movement that encourages people to ‘eat better, move more, and live longer’ (www.nhs.uk/Change4life). The campaign began in 2009, with the aim of making weight and physical activity ‘hot-topics’. Launched in a number of phases, it began by addressing the issue of obesity, before going on to personalising it to individuals and families, and then inspiring and supporting people to change their behaviour. A review of achievements is expected in January 2014.

European Food Framework (EFF)

The EFF outlines core skills, knowledge and understanding for diet (food and drink), active lifestyles (physical activity) and energy balance for young people throughout Europe aged 5–16 years. The Framework provides a consistent, up-to-date and evidence-based consensus, supporting all involved in food, nutrition and lifestyle education, whether part of a formal school curriculum or not. The Framework can be used as: an audit tool in schools to help plan lessons; support for curriculum development; a guide for those developing resources for young people.

Active Kids Get Cooking

Active Kids is a Sainsbury's initiative that encourages children of all ages and abilities to lead healthier and more active lifestyles – eating well is a key element. Through Active Kids, school teachers and Scout or Guide leaders can use dedicated resources to inspire, teach and encourage children to learn about food, healthy eating and cooking. The initiative was developed in collaboration with the British Nutrition Foundation and supported by the Department for Education (https://activekids.sainsburys-live-well-for-less.co.uk).

Eat Like a Champ

This project funded by Danone encourages healthy eating and physical activity by offering primary schools a free toolkit of resources including lesson plans, card games and dance videos recorded by Diversity (winners of Britain's Got Talent in 2009). In 2012, evaluation of the resources was carried out by the Children's Food Trust. The research showed that children who took part in Eat Like A Champ shifted behaviours towards healthier eating habits (www.eatlikeachamp.co.uk).

Food Dudes Health

The award-winning programmes include Food Dudes Full Force for primary schools and special schools, Next Generation and Food Dudes Forever to maintain the effects in schools, the Early Years Food Dudes Programme, and Choice Architecture for School Catering. Other on-going developments include a home-based service and a physical activity programme (www.fooddudes.co.uk).

Focus on Food

A campaign (linked to the Food for Life Partnership) to raise the profile and importance of food education nationally – using food as a key experience in learning about the social importance of food. Cooking buses and school visits can be arranged (for a fee). Food education resources are available (www.focusonfood.org).

FutureChef

Springboard's FutureChef inspires young people aged 12–16 years to learn to cook by developing their culinary talent and informing them about entry routes into the hospitality industry. FutureChef directly introduces young people to cooking, helps to develop their skills, develops direct work experience in the hospitality industry and provides expert advice on the career options and entry routes available. It supports the partnership between teachers and young people and chefs (futurechef.uk.net/).

Phunky Foods

A comprehensive healthy lifestyles programme developed by registered nutritionists and consultant teachers. A curriculum and topic-linked solution to Healthy Eating and Physical Activity throughout schools, it covers Early Years, Primary and Special Needs settings, where children are taught key messages through art, drama, music, play and hands-on experience with food. Services provided for a fee (www.phunkyfoods.com).

Tesco Farm to Fork

Farm to Fork, part of the Tesco ‘Eat Happy Project’, is a national food education programme launched in January 2014 to help reconnect children with where food comes from. The programme is offered to all primary schools across the UK to learn more about food with selected Tesco suppliers as well as using Tesco stores as classrooms. Dedicated curriculum-linked resources are available to support teaching of cookery in classrooms. The initiative was developed with teachers and in collaboration with TTS. The cooking skills and recipe support has been developed in collaboration with the British Nutrition Foundation (www.eathappyproject.com).

Warburtons School Visitor Programme

Twenty Warburtons School Visitors are based across the UK and deliver free healthy eating and practical food workshops to primary schools (www.warburtons.co.uk/corporate/responsibility/best-for-the-community/school-visitors).

References

  1. Top of page
  2. Summary
  3. Introduction
  4. Nutritional requirements of schoolchildren
  5. Findings of the National Diet and Nutrition Surveys (NDNS)
  6. Nutrition and health in childhood
  7. Food provision in school
  8. Food in the curriculum
  9. Selected initiatives and organisations of relevance to child nutrition
  10. Acknowledgement
  11. Conflict of interest
  12. References
  • Absoud M, Cummins C, Lim MJ et al. (2011) Prevalence and predictors of vitamin D insufficiency in children: a Great Britain population based study. PLoS ONE 6: e22179.
  • Ackerman KE & Misra M (2011) Bone health in adolescent athletes with a focus on female athlete triad. Physician and Sports Medicine 39: 131141.
  • Adams J, O'Keeffe M & Adamson A (2005) Change in snacking habits and obesity over 20 years in children aged 11 to 12 years. Project NO9 019 (Jan–Sept 2005). Final report to the Food Standards Agency.
  • Adamson A, White M, Stead M et al. (2011) The process and impact of change in the school food policy on food and nutrient intake of children aged 4–7 and 11–12 years both in and out of school; a mixed methods approach. Public Health Research Consortium, London.
  • Adamson A, Spence S, Reed L et al. (2013) School food standards in the UK: implementation and evaluation. Public Health Nutrition 16: 968981.
  • Adolphus K, Lawton CL & Dye L (2013) The effects of breakfast on behaviour and academic performance in children and adolescents. Frontiers in Human Neuroscience 7 (Article 425): 128.
  • Althuis MD & Weed DL (2013) Evidence mapping: methodologic foundations and application to intervention and observational research on sugar-sweetened beverages and health outcomes. American Journal of Clinical Nutrition 98: 755768.
  • Asero R, Ballmer-Weber BK, Byer K et al. (2006) IgE-mediated food allergy diagnosis: current status and new perspectives. Molecular Nutrition and Food Research 51: 135147.
  • Aylin P, Williams S & Bottle A (2005) Obesity and type 2 diabetes in children 1996–7 to 2003–4. British Medical Journal 331: 1167.
  • Barton M (2012) Childhood obesity: a life-long health risk. Acta Pharmacologica Sinica 33: 189193.
  • Bates B, Lennox A & Swan G (2010) National Diet and Nutrition Survey. Headline results from Year 1 of the Rolling Programme 2008/2009. Food Standards Agency, Department of Health, London.
  • Bates B, Lennox A, Bates C et al. (2011) National Diet and Nutrition Survey. Headline results from Years 1 and 2 (combined) of the Rolling Programme (2008/09–2009/10). Department of Health, Food Standards Agency, London.
  • Bates B, Lennox A, Prentice A et al. (2012) National Diet and Nutrition Survey. Headline results from Years 1, 2 and 3 (combined) of the Rolling Programme (2008/09–2010/11). Department of Health, Food Standards Agency, London.
  • Becker E, Boreham R, Chaudhury M et al. (2006) Health Survey for England 2004. The health of minority ethnic groups. Volume 1. Vol. 1 (Sproston, K and Mindell, J. eds.) The Information Centre, Leeds.
  • Bellisle F, Drewnowski A, Anderson GH et al. (2012) Sweetness, satiation, and satiety. Journal of Nutrition 142: 1149S1154.
  • Benelam B (2009) Satiation, satiety and their effects on eating behaviour. Nutrition Bulletin 34: 126173.
  • Benelam B & Wyness L (2010) Hydration and health: a review. Nutrition Bulletin 35: 325.
  • Benton D, Maconie A & Williams C (2007) The influence of the glycaemic load of breakfast on the behaviour of children in school. Physiology & Behavior 92: 717724.
  • BHF (British Heart Foundation) (2009) Couch Kids: The Nations Future. British Heart Foundation: London.
  • Biro FM & Wien M (2010) Childhood obesity and adult morbidities. American Journal of Clinical Nutrition 91: 1499S1505.
  • Black MM (2003) Micronutrient deficiencies and cognitive functioning. The Journal of Nutrition 133: 3927S3931.
  • Bleich SN, Segal J, Wu Y et al. (2013) Systematic review of community-based childhood prevention studies. Pediatrics 132: e201210.
  • BNF (British Nutrition Foundation) (1999) Oral Health. Diet and Other Factors. Wiley-Blackwell: Oxford.
  • BNF (British Nutrition Foundation) (2013) Nutrition and Development: Short and Long Term Consequences for Health. Wiley-Blackwell: Oxford.
  • Borys JM, Le Bodo Y, Jebb SA et al. (2012) EPODE approach for childhood obesity prevention: methods, progress and international development. Obesity Reviews 13: 299315.
  • Bradshaw P, Bromley C, Corbett J et al. (2012) The Scottish Health Survey 2011, Vol. 2: Children. The Scottish Government: Edinburgh.
  • Brindal E, Baird D, Danthiir V et al. (2012) Ingesting breakfast meals of different glycaemic load does not alter cognition and satiety in children. European Journal of Clinical Nutrition 66: 11661171.
  • Brockman R, Jargo R, Fox KR et al. (2009) ‘Get off the sofa and go and play’: family and socioeconomic influences on the physical activity of 10–11 year old children. BMC Public Health 9: 253.
  • Brodersen HN, Steptoe A, Boniface DR et al. (2007) Trends in physical activity and sedentary behavior in adolescence: ethnic anc socioeconomic differences. British Journal of Sports Medicine 41: 140144.
  • Bromley C, Sproston K & Shelton N (2005) The Scottish Health Survey 2003. Children. The Scottish Executive: Edinburgh.
  • Bromley C, Given L & Ormston R (2010) The Scottish Health Survey 2009, Vol. 1: Main report. Scottish Centre for Social Research: Edinburgh.
  • Brooke HL, Corder K, Griffin SJ et al. (2013) More of the same or a change of scenery: an observational study of variety and frequency of physical activity in British children. BMC Public Health 13: 761.
  • Brug J, van Stralen MM, te Velde SJ et al. (2012) Differences in weight status and energy-balance related behaviors among schoolchildren across Europe: the ENERGY-project. PLoS ONE 7: e34742.
  • Brunton G, Harden A, Rees R et al. (2003) Children and physical activity: a systematic review of barriers and facilitators. EPPI-Centre, Social Science Research Unit, Institute of Education, University of London, London.
  • BSACI (British Society for Allergy and Clinical Immunology) (2013) Food allergy and food intolerance. Available at: http://www.bsaci.org/resources/food-allergy-and-food-intolerance (accessed 21 October 2013).
  • Burks AW, Tang M, Sicherer S et al. (2012) ICON: food allergy. Journal of Allergy and Clinical Immunology 129: 906920.
  • Butland B, Jebb S, Kopelman P et al. (2007) Tackling Obesities: Future Choices – Project Report, 2nd edn. Government Office for Science: London.
  • Butte NF (2000) Fat intake of children in relation to energy requirements. American Journal of Clinical Nutrition 72: 1246S1252.
  • Buttriss J (2002a) Nutrition, Health and Schoolchildren. Nutrition Bulletin 27: 275316.
  • Buttriss J (2002b) Adverse Reactions to Food. Blackwell Science for the British Nutrition Foundation: London.
  • Celermajer DS & Ayer JG (2006) Childhood risk factors for adult cardiovascular disease and primary prevention in childhood. Heart 92: 17011706.
  • Chiarelli F & Marcovecchio ML (2008) Insulin resistance and obesity in childhood. European Journal of Endocrinology 159: S6774.
  • Chief Medical Officer (2013) Chief Medical Officer's annual report 2012: Our children deserve better: Prevention pays. Department of Health. Available at: https://www.gov.uk/government/publications/chief-medical-officers-annual-report-2012-our-children-deserve-better-prevention-pays (accessed November 2013).
  • Chief Medical Officers (2011) Physical activity guidelines for children and young people (5–18 years). Factsheet 3. Available at: https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/213739/dh_128144.pdf (accessed 19 August 2013).
  • Cole TJ & Lobstein T (2012) Extended international (IOTF) body mass index cut-offs for thinness, overweight and obesity. Pediatric Obesity 7: 284294.
  • Cole TJ, Freeman JV & Preece MA (1995) Body mass index reference curves for the UK, 1990. Archives of Diseases in Childhood 73: 2529.
  • Cooper SB, Bandelow S, Nute ML et al. (2012) Breakfast glycaemic index and cognitive function in adolescent school children. British Journal of Nutrition 107: 18231832.
  • CSU (Central Survey Unit) (2011) Young Persons' Behaviour and Attitudes Survey Bulletin. Northern Ireland Research and Statistics agency: Belfast.
  • Craig R & Mindell J (2012) Health Survey for England 2011. The NHS Information Centre: London.
  • Craig R, Mindell J & Hirani V (2009a) Health Survey for England 2008, Vol. 2, Methods and Documentation. The NHS Information Centre: London.
  • Craig R, Mindell J & Hirani V (2009b) Health Survey for England 2008. Physical activity and fitness. Vol. 1. The NHS Information Centre: London.
  • CWT (The Caroline Walker Trust) (1992) Nutritional Guidelines for School Meals. Report of an Expert Working Group. The Caroline Walker Trust, London.
  • Darling AL, Millward DJ, Torgerson DJ et al. (2009) Dietary protein and bone health: a systematic review and meta-analysis. American Journal of Clinical Nutrition 90: 16741692.
  • Davies G, Neville J, Rooney E et al. (2013) National Dental Epidemiology Programme for England: oral health survey of five-year-old children 2012. A report on the prevalence and severity of dental decay. Public Health England, London.
  • de la Hunty A, Gibson S & Ashwell M (2013) Does regular breakfast cereal consumption help children and adolescents stay slimmer? A systematic review and meta-analysis. Obesity Facts 6: 7085.
  • Defeyter MA, Graham PL, Walton J et al. (2010) Breakfast clubs: availability for British schoolchildren and the nutritional, social and academic benefits. Nutrition Bulletin 35: 245253.
  • DeMattia L, Lemont L & Meurer L (2007) Do interventions to limit sedentary behaviours change behaviour and reduce childhood obesity? A critical review of the literature. Obesity Reviews 8: 6981.
  • DCSF (Department for Children Schools and Families) (2008) The Education (Nutritional Standards and Requirements for School Food) (England) Regulations 2007 (SI 2007/2359) as amended by the Education (Nutritional Standards and Requirements for School Food) (England) (Amendment) Regulations 2008 (SI 2008/1800). Department for Children Schools and Families, London.
  • DH (Department of Health) (1991) Dietary Reference Values for Food, Energy and Nutrients for the United Kingdom. In Report on Health Social Subjects 41Her Majesty's Stationery Office, London.
  • DH (Department of Health) (2008) National Child Measurement Programme: 2006/07 School Year, Headline Results. The Information Centre: London.
  • DH (Department of Health) (2010) School Fruit and Vegetable Scheme. Department of Health, London.
  • DH, SSPS (Department of Health, Social Services and Public Safety) (2012) Health Survey Northern Ireland: First results from the 2011/12 survey. Bulletin 1. Department of Health, Social Services and Public Safety, Belfast. Available at: http://www.dhsspsni.gov.uk/health_survey_northern_ireland_-_first_results_from_the_2011-12_survey.pdf (accessed 26 August 2013).
  • Dhuper S, Buddhe S & Patel S (2013) Managing cardiovascular risk in overweight children and adolescents. Paediatric Drugs 15: 181190.
  • Dimbleby H & Vincent J (2013) The school food plan. Available at: http://www.schoolfoodplan.com/ (accessed 07 September 2013).
  • DoE (Department of Education) (2011) Statutory instrument 2011 No. 1190. The education (nutritional standards and requirements for school food) (England) (amendment) regulations. Available at: http://www.legislation.gov.uk/uksi/2011/1190/made (accessed 28 September 2013).
  • Donin AS, Nightingale CM, Owen CG et al. (2010) Nutritional composition of the diets of South Asian, black African-Caribbean and white European children in the United Kingdom: the Child Heart and Health Study in England (CHASE). British Journal of Nutrition 104: 276285.
  • Drewnowski A & Bellisle F (2007) Liquid calories, sugar, and body weight. American Journal of Clinical Nutrition 85: 651661.
  • Du Toit G, Katz Y, Sasieni P et al. (2008) Early consumption of peanuts in infancy is associated with a low prevalence of peanut allergy. The Journal of Allergy and Clinical Immunology 122: 984991.
  • Dunton GF, Kaplan J, Wolch J et al. (2009) Physical environmental correlates of childhood obesity: a systematic review. Obesity Reviews 10: 393402.
  • EC (European Commission) (2008) Commission Directive 2008/100/EC of 28 October 2008 amending Council Directive 90/496/EEC on nutrition labeling for foodstuffs as regards recommended daily allowances, energy conversion factors and definitions. Official Journal of the European Union 51: 912. 29.10.2008.
  • EFSA (European Food Safety Authority) (2007) Statement of the Scientific Panel on Dietetic Products, Nutrition and Allergies on a request from the Commission related to dietary fibre (Request No EFSA-Q-2007-121) expressed on 6 July 2007.
  • EFSA (European Food Safety Authority) (2008a) Xylitol chewing gum/pastilles and reduction of the risk of tooth decay. EFSA Journal 852: 115.
  • EFSA (European Food Safety Authority) (2008b) Scientific substantiation of a health claim related to calcium and bone growth pursuant to Article 14 of Regulation (EC) No 1924/2006. EFSA Journal 826: 111.
  • EFSA (European Food Safety Authority) (2008c) Scientific substantiation of a health claim related to calcium and vitamin D and bone strength pursuant to Article 14 of Regulation (EC) No 1924/2006. EFSA Journal 828: 113.
  • EFSA (European Food Safety Authority) (2009) Scientific Opinion on the substantiation of health claims related to iron and formation of red blood cells and haemoglobin (ID 249, ID 1589), oxygen transport (ID 250, ID 254, ID 256), energy-yielding metabolism (ID 251, ID 1589), function of the immune system (ID 252, ID 259), cognitive function (ID 253) and cell division (ID 368) pursuant to Article 13(1) of Regulation (EC) No 1924/2006. EFSA Journal 7: 1215.
  • EFSA (European Food Safety Authority) (2010a) Scientific Opinion on Dietary Reference Values for carbohydrates and dietary fibre. EFSA Panel on Dietetic Products, Nutrition, and Allergies. EFSA Journal 8: 1462.
  • EFSA (European Food Safety Authority) (2010b) Scientific Opinion on Dietary Reference Values for water. EFSA Panel on Dietetic Products, Nutrition, and Allergies (NDA). EFSA Journal 8: 1459.
  • Eilander A, Gera T, Sachdev HS et al. (2010) Multiple micronutrient supplementation for improving cognitive performance in children: systematic review of randomized controlled trials. American Journal of Clinical Nutrition 91: 115130.
  • Ells LJ, Hillier FC, Shucksmith J et al. (2008) A systematic review of the effect of dietary exposure that could be achieved through normal dietary intake on learning and performance of school-aged children of relevance to UK schools. British Journal of Nutrition 100: 927936.
  • EPSM (Expert Panel on School Meals) (2002) Hungry for Success. A Whole School Approach to School Meals in Scotland. Scottish Government: Edinburgh.
  • Evans CE, Cleghorn CL, Greenwood DC et al. (2010a) A comparison of British school meals and packed lunches from 1990 to 2007: meta-analysis by lunch type. British Journal of Nutrition 104: 474487.
  • Evans CE, Greenwood DC, Thomas JD et al. (2010b) SMART lunch box intervention to improve the food and nutrient content of children's packed lunches: UK wide cluster randomised controlled trial. Journal of Epidemiology and Community Health 64: 970976.
  • Eyre EL, Duncan MJ, Smith EC et al. (2013) Objectively measured patterns of physical activity in primary school children in Coventry: the influence of ethnicity. Diabetic Medicine 30: 939945.
  • Fairclough SJ, Beighle A, Erwin H et al. (2012) School day segmented physical activity patterns of high and low active children. BMC Public Health 12: 406.
  • Falkingham M, Abdelhamit A, Curtis P et al. (2010) The effects of oral iron supplementation on cognition in older children and adults: a systematic review and meta-analysis. Nutrition Journal 9: 4.
  • Finnerty T, Reeves S, Dabinett J et al. (2010) Effects of peer influence on dietary intake and physical activity in schoolchildren. Public Health Nutrition 13: 376383.
  • Fisher JO & Kral TVE (2007) Super-size me: portion size effects on young children's eating. Physiology & Behavior 94: 3947.
  • Fisher JO, Liu Y, Birch LL et al. (2007) Effects of portion size and energy density on young children's intake at a meal. American Journal of Clinical Nutrition 86: 174179.
  • Flynn JT & Falkner BE (2011) Obesity hypertension in adolescents: epidemiology, evaluation, and management. Journal of Clinical Hypertension 13: 323331.
  • Fogelholm M, Nuutinen O, Pasanen M et al. (1999) Parent-child relationship of physical activity patterns and obesity. International Journal of Obesity 23: 12621268.
  • Forshee RA, Anderson PA & Storey ML (2008) Sugar-sweetened beverages and body mass index in children and adolescents: a meta-analysis. American Journal of Clinical Nutrition 87: 16621671.
  • FSA (Food Standards Agency) (2008) Report of 2008 T07 Food Allergy and Intolerance Research Programme Review. Food Standards Agency: London.
  • FSA (Food Standards Agency) (2009) Peanuts during Pregnancy, Breastfeeding and Early Childhood, Vol. 2011. Food Standards Agency: London.
  • Freedman DS, Kettel Khan L, Serdula MK et al. (2005) The relation of childhood BMI to adult adiposity: the Bogalusa Heart Study. Pediatrics 115: 2227.
  • Gibson SA (2003) Micronutrient intakes, micronutrient status and lipid profiles among young people consuming different amounts of breakfast cereals: further analysis of data from the National Diet and Nutrition Survey of Young People aged 4 to 18 years. Public Health Nutrition 6: 815820.
  • Gibson SA & Gunn P (2011) What's for breakfast? Nutritional implications of breakfast habits: insights from the NDNS dietary records. Nutrition Bulletin 36: 7886.
  • Gibson-Moore H (2013) Improving hydration in children: a sensible guide. Nutrition Bulletin 38: 236242.
  • Gilsenan MB, de Bruin EA & Dye L (2009) The influence of carbohydrate on cognitive performance: a critical evaluation from the perspective of glycaemic load. British Journal of Nutrition 101: 941949.
  • Gorley T, Marshall SJ, Biddle SJH et al. (2007) The prevalence of leisure time sedentary behaviour and physical activity in adolescent girls: an ecological momentary assessment approach. International Journal of Pediatric Obesity 2: 227234.
  • Gregory J, Lowe S, Bates CJ et al. (2000) National Diet and Nutrition Survey: young people aged 4 to 18 years. Report of the Diet and Nutrition Survey, Vol. 1. The Stationary Office: London.
  • Griffiths LJ, Cortina-Borja M, Sera F et al. (2013) How active are our children? Findings from the Millennium Cohort Study. BMJ Open 3: e002893.
  • Gupta R, Sheikh A, Strachan DP et al. (2007) Time trends in allergic disorders in the UK. Thorax 62: 9196.
  • Haines L & Kramer Z (2009) Growing up with Diabetes: children and young people with diabetes in England. Royal College of Paediatrics and Child Health Science and Research Department, London.
  • Harper C & Wood L (2009) Please Sir? Can We Have Some More? – Lessons from Free School Meal Initiatives. School Food Trust: Sheffield.
  • Harro M & Riddoch CJ (2000) Physical activity. In: Pediatric Exercise Science and Medicine, Vol. 1, ( N Armstrong , W Van Mechelen eds), pp. 7784. Oxford University Press: Oxford.
  • Hauner H, Bechthold A, Boeing H et al. (2012) Evidence-based guideline of the German Nutrition Society: carbohydrate intake and prevention of nutrition-related diseases. Annals of Nutrition and Metabolism 60 (Suppl. 1): 158.
  • He FJ & MacGregor GA (2006) Importance of salt in determining blood pressure in children: meta-analysis of controlled trials. Hypertension 48: 861869.
  • Hind K & Burrows M (2007) Weight-bearing exercise and bone mineral accrual in children and adolescents: a review of controlled trials. Bone 40: 1427.
  • Holick MF (2007) Vitamin D deficiency. New England Journal of Medicine 357: 266281.
  • Holmes BA, Kaffa N, Campbell K et al. (2012) The contribution of breakfast cereals to the nutritional intake of materially deprived UK population. European Journal of Clinical Nutrition 66: 1017.
  • Hoyland A, Dye L & Lawton CL (2009) A systematic review of the effect of breakfast on the cognitive performance of children and adolescents. Nutrition Research Reviews 22: 220243.
  • HPA(NI) (Health Promotion Agency for Northern Ireland) (2008) Nutritional Standards for School Lunches: A Guide for Implementation. Health Promotion Agency for Northern Ireland: Belfast.
  • HSCIC (The Health and Social Care Information Centre) (2012) National Child Measurement Programme: England, 2011/12 school year. The Health and Social Care Information Centre, Leeds.
  • Hsia Y, Neubert AC, Rani F et al. (2009) An increase in the prevalence of type 1 and 2 diabetes in children and adolescents: results from prescription data from a UK general practice database. British Journal of Clinical Pharmacology 67: 242249.
  • Huncharek M, Muscat J & Kupelnick B (2008) Impact of dairy products and dietary calcium on bone–mineral content in children: results of a meta-analysis. Bone 43: 312321.
  • Inchley JC, Currie DB, Todd JM et al. (2005) Persistent socio-demographic differences in physical activity among Scottish schoolchildren 1990–2002. European Journal of Public Health 15: 386388.
  • Ingwersen J, Defeyter MA, Kennedy DO et al. (2007) A low glycaemic index breakfast cereal preferentially prevents children's cognitive performance from declining throughout the morning. Appetite 49: 240244.
  • Jago R, Brockman R, Fox KR et al. (2009) Friendship groups and physical activity: qualitative findings on how physical activity is initiated and maintained among 10–11 year old children. International Journal of Behavioral Nutrition and Physical Activity 6: 4.
  • Jesudason D & Clifton P (2011) The interaction between dietary protein and bone health. Journal of Bone and Mineral Metabolism 29: 114.
  • Kaisari P, Yannakoulia M & Panagiotakos DB (2013) Eating frequency and overweight and obesity in children and adolescents: a meta-analysis. Pediatrics 131: 958967.
  • Katz DL, O'Connell M, Njike VY et al. (2008) Strategies for the prevention and control of obesity in the school setting: systematic review and meta-analysis. International Journal of Obesity 32: 17801789.
  • Kennedy D, Jackson P, Elliott J et al. (2009) Cognitive and mood effects of 8 weeks' supplementation with 400 mg or 1000 mg of the omega-3 essential fatty acid docosahexaenoic acid (DHA) in healthy children aged 10–12 years. Nutritional Neuroscience 12: 4856.
  • Kirby A, Woodward A, Jackson S et al. (2010) A double-blind, placebo-controlled study investigating the effects of omega-3 supplementation in children aged 8–10 years from a mainstram school popluation. Research in Developmental Disabilities 31: 718730.
  • Krahnstoever Davison K, Cutting TM & Birch LL (2003) Parents' Activity-related parenting practices predict girls' physical activity. Medicine and Science in Sport and Exercise 35: 15891595.
  • LACA (Local Authority Caterers' Association) (2004) School Meals Survey 2004. LACA: Woking.
  • Lack G (2012) Update on risk factors for food allergy. Journal of Allergy and Clinical Immunology 129: 11871197.
  • Lader D, Chadwick B, Chestnutt I et al. (2005) Children's Dental Health in the United Kingdom, 2003. Summary Report. Office for National Statistics: London.
  • Lanham-New SA, Thompson RL, More J et al. (2007) Importance of vitamin D, calcium and exercise to bone health with specific reference to children and adolescents. Nutrition Bulletin 32: 364377.
  • Lanham-New SA, Buttriss J, Miles L et al. (2011) Proceedings of the rank forum on vitamin D. British Journal of Nutrition 105: 144156.
  • Larson Ode K, Frohner BI & Nathan BM (2009) Identification and treatment of metabolic complications in pediatric obesity. Reviews in Endocrine & Metabolic Disorders 10: 167188.
  • Laska MN, Murray DM, Lytle LA et al. (2012) Longitudinal associations between key dietary behaviors and weight gain over time: transitions through the adolescent years. Obesity 20: 118125.
  • Lloyd LJ, Langley-Evans SC & McMullen S (2010) Childhood obesity and adult cardiovascular disease risk: a systematic review. International Journal of Obesity 34: 1828.
  • Lloyd LJ, Langley-Evans SC & McMullen S (2012) Childhood obesity and risk of the adult metabolic syndrome: a systematic review. International Journal of Obesity 36: 111.
  • Lunn J & Buttriss J (2007) Carbohydrates and dietary fibre. Nutrition Bulletin 32: 2164.
  • MacGregor A & Sheehy C (2005) Evaluation of Free Fruit in Schools Initiative. Scottish Centre for Social Research: Edinburgh.
  • Macpherson LMD, Ball G, Conway DI et al. (2012) National Dental Inspection Programme 2012. Report of the 2012 Detailed National Dental Inspection Programme of Primary 1 Children and the Basic Inspection of Primary 1 and Primary 7 Children. The Scottish Dental Epidemiology Coordinating Committee by ISD Scotland, Edinburgh.
  • Madsen C (2005) Prevalence of food allergy: an overview. Proceedings of the Nutrition Society 64: 413417.
  • Malik VS, Schulze MB & Hu FB (2006) Intake of sugar-sweetened beverages and weight gain: a systematic review. American Journal of Clinical Nutrition 84: 274288.
  • Malik VS, Willet WC & Hu FB (2009) Sugar-sweetened beverages and BMI in children and adolescents: re-analysis of a meta-analysis. American Journal of Clinical Nutrition 89: 438439.
  • Malik VS, Pan A, Willet WC et al. (2013) Sugar-sweetened beverages and weight gain in children and adults: a systematic review and meta-analysis. American Journal of Clinical Nutrition 98: 10841102.
  • Malina RM (1996) Tracking of physical activity and physical fitness across the lifespan. Research Quarterly for Exercise and Sport 67: S4857.
  • Mattes RD, Shikany JM, Kaiser KA et al. (2011) Nutritively sweetened beverage consumption and body weight: a systematic review and meta-analysis of randomized experiments. Obesity 12: 345365.
  • McBridge D, Keil T, Graunenhenrich I et al. (2012) The EuroPrevall birth cohort study on food allergy: baseline characteristics of 12 000 neworns and their families from nine European countries. Pediatric Allergy and Immunology 23: 230239.
  • McCrindle BW (2010) Assessment and management of hypertension in children and adolescents. Nature Reviews Cardiology 7: 155163.
  • Mensink GBM, Fletcher R, Gurinovic M et al. (2013) Mapping low intake of micronutrients across Europe. British Journal of Nutrition 110: 755773.
  • Merrett MCW, Conway DI, Goold S et al. (2009) Report of the 2009 Survey of P7 Children. Scottish Dental Epidemiological Co-ordinating Committee, Edinburgh.
  • Micha R, Rogers PJ & Nelson M (2010) The glycaemic potency of breakfast and cognitive function in school children. European Journal of Clinical Nutrition 64: 948957.
  • Micha R, Rogers PJ & Nelson M (2011) Glycaemic index and glycaemic load of breakfast predict cognitive function and mood in school children: a randomised controlled trial. British Journal of Nutrition 106: 15521561.
  • Miles L (2007) Physical activity and health. Nutrition Bulletin 32: 314363.
  • Miller R, Benelam B, Stanner SA et al. (2013) Is snacking good or bad for health: an overview. Nutrition Bulletin 38: 302322.
  • Mills ENC, Mackie AR, Burney P et al. (2007) The prevalence, cost and basis of food allergy across Europe. Allergy 62: 717722.
  • Moore L & Tapper K (2008) The impact of school fruit tuck shops and school food policies on children's fruit consumption: a cluster randomised trial of schools in deprived areas. Journal of Epidemiology and Community Health 62: 926931.
  • Morgan M, Monaghan N, Pickles T et al. (2010) An Atlas of Oral Health in Wales. Volume 1. Survey of rising 12 year olds 2008/09. Welsh Oral Health Information Unit/Public Health Wales, Cardiff.
  • Morgan M, Monaghan N & Johnson I (2013) Picture of Oral Health 2012. Dental Epidemiological Survey of 5 Year Olds 2001-12.Cardiff University/Public Health Wales, Cardiff.
  • Nathan BM & Moran A (2008) Metabolic complications of obesity in childhood and adolescence: more than just diabetes. Current Opinion in Endocrinology, Diabetes and Obesity 15: 2129.
  • Nelson M, Bradbury J, Poulter J et al. (2004) School Meals in Secondary Schools in England. Research Report No 557. Department for Education and Skills, Food Standards Agency, London.
  • Nelson M, Nicholas J, Suleiman S et al. (2006) School Meals in Primary Schools in England. Research Report No 753. Department for Education and Skills, Food Standards Agency, London.
  • Nelson M, Erens B, Bates B et al. (2007) Low Income Diet and Nutrition Survey. Food Consumption, Nutrient Intake. Vol. 2. Food Standards Agency: London.
  • NICE (National Institute of Clinical Excellence) (2006a) Obesity: Guidance on the Prevention, Identification, Assessment and Management of Overweight and Obesity in Adults and Children. NICE: London.
  • NICE (National Institute of Clinical Excellence) (2006b) Obesity: the Prevention, Identification, Assessment and Management of Overweight and Obesity in Adults and Children. NICE: London.
  • NICE (National Institute of Clinical Excellence) (2013) Managing Overweight and Obesity among Children and Young People Lifestyle Weight Management Services. NICE Public Health Guidance 47. NICE: London.
  • Nixon CA, Moore HJ, Douthwaite W et al. (2012) Identifying effective behavioural models and behaviour change strategies underpinning preschool- and school-based obesity prevention interventions aimed at 4–6-year-olds: a systematic review. Obesity Reviews 13 (Suppl. 1): 106117.
  • Pan A & Hu FB (2011) Effects of carbohydrates on satiety: differences between liquid and solid food. Current Opinion in Clinical Nutrition and Metabolic Care 14: 385390.
  • PANNW (Physical Activity and Nutrition Network Wales) (2009) Fruit Tuck Shops. Cardiff.
  • Park MH, Falconer C, Viner RM et al. (2012) The impact of childhood obesity on morbidity and mortality in adulthood: a systematic review. Obesity Reviews 13: 9851000.
  • Passmore S & Harris G (2004) Education, health and school meals: a review of policy changes in England and Wales over the past century. Nutrition Bulletin 29: 221227.
  • Pate RR, O'Neill JR & Lobelo F (2008) The evolving definition of sedentary. Exercise and Sports Sciences Reviews 34: 173178.
  • Pearce J, Harper H, Haroun D et al. (2011) Key differences between school lunches and packed lunches in primary schools in England in 2009. Public Health Nutrition 14: 15071510.
  • Pendry L, Lashkari G & Bewley H (2004) 2003 Children's Dental Health Survey. Technical Report. Office for National Statistics, London.
  • Pettifor JM & Prentice A (2011) The role of vitamin D in paediatric bone health. Best Practice & Research Clinical Endocrinology & Metabolism 25: 573584.
  • Phillips F (2004) Diet and bone health. Nutrition Bulletin 29: 99110.
  • Prentice A (2013) Standing on the shoulders of giants: understanding calcium and vitamin D requirements. Nutrition Bulletin 38: 323331.
  • Prentice A, Schoenmakers I, Laskey MA et al. (2006) Nutrition and bone growth and development. Proceedings of the Nutrition Society 65: 348360.
  • Prentice-Dunn H & Prentice-Dunn S (2012) Physical activity, sedentary behavior, and childhood obesity: a review of cross-sectional studies. Psychology, Health & Medicine 17: 255273.
  • Reilly JJ (2008) Physical activity, sedentary behaviour and energy balance in the preschool child: opportunities for early obesity prevention. Proceedings of the Nutrition Society 67: 317325.
  • Riddoch CJ, Mattocks C, Deere K et al. (2007) Objective measurement of levels and patterns of physical activity. Archives of Diseases in Childhood 92: 963969.
  • Ridler C, Dinsdale H & Rutter H (2013) National Child Measurement Programme: Changes in Children's Body Mass Index between 2006/07 and 2011/12. National Obesity Observatory: Oxford.
  • Rodriguez-Rodriguez E, Palmeros-Exsome C, Lopez-Sobaler AM et al. (2011) Preliminary data on the association between waist circumference and insulin resistance in children without a previous diagnosis. European Journal of Pediatrics 170: 3543.
  • Rooney E, Davies G, Neville J et al. (2010) NHS Dental Epidemiology Programme for England. Oral Health Survey of 12 year old Children 2008/2009. National Health Service, London.
  • SACN (Scientific Advisory Committee on Nutrition) (2003) Salt and Health. SACN: London.
  • SACN (Scientific Advisory Committee on Nutrition) (2007) Update on Vitamin D. In Position statement of the Scientific Advisory Committee on Nutrition. SACN: London.
  • SACN (Scientific Advisory Committee on Nutrition) (2008) The Nutritional Wellbeing of the British Population. SACN: London.
  • SACN (Scientific Advisory Committee on Nutrition) (2010) Iron and Health. SACN: London.
  • SACN (Scientific Advisory Committee on Nutrition) (2011) Dietary Reference Values for Energy. SACN: London.
  • Sandercock G, Angus C & Barton J (2010) Physical activity levels of children living in different built environments. Preventive Medicine 50: 193198.
  • Sandhu J, Ben-Shlomo Y, Cole TJ et al. (2006) The impact of childhood body mass index on timing of puberty, adult stature and obesity: a follow-up study based on adolescent anthropometry recorded at Christ's Hospital (1936–1964). International Journal of Obesity 30: 1422.
  • School Food Top Marks (2009a) Nutritional standards for school lunches. Health Promotion Agency; Department of Education; Department of Health, Social Services and Public Safety, Belfast.
  • School Food Top Marks (2009b) Nutritional standards for other food and drinks in schools. Health Promotion Agency; Department of Education; Department of Health, Social Services and Public Safety, Belfast.
  • SFT (School Food Trust) (2008a) A Guide to Introducing the Government's Food-Based and Nutrient-Based Standards for School Lunches. School Food Trust: Sheffield.
  • SFT (School Food Trust) (2008b) The Impact of Primary School Breakfast Clubs in Deprived Areas of London. School Food Trust: Sheffield.
  • SFT (School Food Trust) (2012a) Primary School Food Survey 2009. 1. School lunch: provision, selection and consumption. Revised report. School Food Trust: Sheffield.
  • SFT (School Food Trust) (2012b) Secondary School Food Survey 2011. 1. School lunch: provision, selection and consumption. School Food Trust: Sheffield.
  • SG (The Scottish Government) (2007) Schools (Health Promotion and Nutrition) (Scotland) Act 2007. The Scottish Government: Edinburgh.
  • SG (The Scottish Government) (2008a) Healthy Eating in Schools. A guide to implementing the nutritional requirements for food and drink in schools (Scotland) regulations 2008. The Scottish Government: Edinburgh.
  • SG (The Scottish Government) (2008b) The Nutritional Requirements for Food and Drink in Schools (Scotland) Regulations 2008. The Scottish Government: Edinburgh.
  • SG (The Scottish Government) (2010) Healthy Eating in Schools: Supplementary Guidance on Diet and Nutrition for Children and Young People with Additional Support Needs. The Scottish Government: Edinburgh.
  • Short KR, Blackett PR, Gardner AW et al. (2009) Vascular health in children and adolescents: effects of obesity and diabetes. Vascular Health and Risk Management 5: 973990.
  • Showell NN, Fawole O, Segal J et al. (2013) A systematic review of home-based childhood obesity prevention studies. Pediatrics 132: e193200.
  • SIGN (2010) Management of Obesity. A national clinical guidance. Scottish Intergollegiate Guidelines Network, Edinburgh.
  • Sinn N (2008) Nutritional and dietary influences on attention deficit hyperactivity disorder. Nutrition Reviews 66: 558568.
  • SMRP (School Meals Review Panel) (2005) Turning the Tables. Transforming School Food. Department for Education and Skills, London.
  • Sproston K & Mindell J (2006) Health Survey for England 2004. The Health of Minority Ethnic Groups. The Information Centre: London.
  • Sproston K & Primatesta P (2003) Health Survey for England 2002. The Health of Children and Young People. Vol. 1. HMSO: London.
  • Steinberger J, Daniels SR, Eckel RH et al. (2009) Progress and challenges in metabolic syndrome in children and adolescents. A scientific statement from the American Heart Association Atherosclerosis, Hypertension, and Obesity in the Young Committee of the Council on Cardiovascular Disease in the Young; Council on Cardiovascular Nursing; and Council on Nutrition, Physical Activity, and Metabolism. Circulation 119: 628647.
  • Stevens GA, Finucane MM, De-Regil LM et al. (2013) Global, regional, and national trends in haemoglobin concentration and prevalence of total and severe anaemia in children and pregnant and non-pregnant women for 1995–2011: a systematic analysis of population-representative data. Lancet Global Health 1: e1625.
  • Summerbell CD, Waters E, Edmunds L et al. (2005) Interventions for preventing obesity in children. Cochrane Database of Systematic Reviews (20): CD001871.
  • Summerbell CD, Douthwaite W, Whittaker V et al. (2009) The association between diet and physical activity and subsequent excess weight gain and obesity assessed at 5 years of age or older: a systematic review of the epidemiological evidence. International Journal of Obesity 33: S188.
  • Szajewska H & Ruszczynski M (2010) Systematic review demonstrating that breakfast consumption influences body weight outcomes in children and adolescents in Europe. Critical Reviews in Food Science and Nutrition 50: 113119.
  • Te Morenga L, Mallard S & Mann J (2012) Dietary sugars and body weight: systematic review and meta-analyses of randomised controlled trials and cohort studies. British Medical Journal 345: e7492.
  • Teeman D, Lynch S, White K et al. (2010) The Third Evaluation of the School Fruit and Vegetable Scheme. National Foundation for Educational Research: Slough.
  • Theobald HE (2005) Dietary calcium and health. Nutrition Bulletin 30: 237277.
  • Vanderpump MP, Lazarus JH, Smyth PP et al. (2011) Iodine status of UK schoolgirls: a cross-sectional survey. Lancet 377 (9782): 20072012.
  • Vartanian LR, Schwartz MB & Brownell KD (2007) Effects of soft drink consumption on nutrition and health: a systematic review and meta-analysis. American Journal of Public Health 97: 667675.
  • Venter C, Pereira B, Grundy J et al. (2006) Incidence of parentally reported and clinically diagnosed food hypersensitivity in the first year of life. Journal of Allergy and Clinical Immunology 117: 11181124.
  • Vereecken CA, Todd J, Roberts C et al. (2006) Television viewing behavior and associations with food habits in different countries. Public Health Nutrition 9: 244250.
  • Voss C & Sandercock G (2010) Aerobic fitness and mode of travel to school in English schoolchildren. Medicine and Science in Sport and Exercise 42: 281287.
  • WAG (Welsh Assembly Government) (2003) Nutrition Standards for School Lunches. Welsh Assembly Government: Cardiff.
  • WAG (Welsh Assembly Government) (2008a) Welsh Health Report 2007. Welsh Assembly Government: Cardiff.
  • WAG (Welsh Assembly Government) (2008b) Appetite for Life Action Plan. In Information Document No: 026/2007. Department for Children, Education, Lifelong Learning and Skills, Welsh Assembly Government, Cardiff.
  • WAG (Welsh Assembly Government) (2009) Welsh Health Survey 2008. Welsh Assembly Government: Cardiff.
  • WAG (Welsh Assembly Government) (2010) Welsh Health Survey 2009. Welsh Assembly Government: Cardiff.
  • Weed DL, Althuis MD & Mink PJ (2011) Quality of reviews on sugar-sweetened beverages and health outcomes: a systematic review. American Journal of Clinical Nutrition 95: 13401347.
  • Weichselbaum E & Buttriss J (2011) Nutrition, health and schoolchildren. Nutrition Bulletin 36: 295355.
  • WG (Welsh Government) (2011) Welsh Health Survey 2010. Welsh Assembly Government: Cardiff.
  • WG (Welsh Government) (2012) The Welsh Health Survey 2011. The Welsh Government: Cardiff.
  • WG (Welsh Government) (2013) The healthy eating in schools (nutritional standards and requirements) (wales) regulations 2013. Available at: http://wales.gov.uk/docs/dcells/consultation/130131draftregulationsen.pdf (accessed 28 September 2013).
  • Whincup PH, Nightingale CM, Owen CG et al. (2010) Early emergence of ethnic differences in type 2 diabetes precursors in the UK: the Child Heart and Health Study in England (CHASE Study). Public Library of Science Medicine 7: e1000263.
  • Williams AJ, Henley WE, Williams CA et al. (2013) Systematic review and meta-analysis of the association between childhood overweight and obesity and primary school diet and physical activity policies. International Journal of Behavioral Nutrition and Physical Activity 10: 101.
  • Williams P (2007) Breakfast and the diets of Australian children and adolescents: an analysis of data from the 1995 National Nutrition Survey. International Journal of Food Science and Nutrition 58: 201216.
  • Williamson C (2010) Breakfast cereals – why all the bad press? Nutrition Bulletin 35: 3033.
  • Winzenberg TM, Shaw KA, Fryer J et al. (2006) Calcium supplementation for improving bone mineral density in children. Cochrane Database of Systematic Reviews (2006): CD005119.
  • Winzenberg TM, Powell S, Shaw KA et al. (2010) Vitamin D supplementation for improving bone mineral density in children. Cochrane Database of Systematic Reviews (2010): CD006944.
  • WHO (World Health Organization) (2000) Obesity: Preventing and Managing the Global Epidemic. WHO Technical Report Series 894. WHO: Geneva.
  • WHO (World Health Organization) (2008) Worldwide Prevalence of Anaemia 1993–2005: WHO Global Database on Anaemia. WHO: Geneva, Switzerland.
  • WHO (World Health Organization) (2010) Global Recommendations on Physical Activity for Health. WHO: Geneva.
  • Wright CM, Parker L, Lamont D et al. (2001) Implications of childhood obesity for adult health: findings from thousand families cohort study. British Medical Journal 323: 12801284.