• Open Access

Dietary intakes of European, Māori, Pacific and Asian adults living in Auckland: the Diabetes, Heart and Health Study

Authors


Correspondence to:
Dr Patricia Metcalf, Division of Epidemiology and Biostatistics, School of Population Health, Tamaki Campus, University of Auckland, Private Bag 92019, Auckland, New Zealand. Fax: 64 9 3737 000; e-mail: p.metcalf@auckland.ac.nz

Abstract

Objective: To compare dietary intakes of European, Māori, Pacific, and Asian men and women living in Auckland.

Methods: Daily nutrient intakes were calculated from a self-administered food frequency questionnaire from participants in a cross-sectional health screening study carried out between 2002 and 2003. Participants were 4,007 Māori, Pacific, Asian and European people (1,915 men, 2,092 women) aged 35 to 74 years.

Results: Compared with Europeans, Māori and Pacific men had higher total energy intakes per day, while Asians had lower intakes. A similar pattern was observed for carbohydrate and fat consumption. While protein and cholesterol consumption tended to be lower in Europeans than the other three ethnic groups, alcohol consumption and calcium intakes were highest among Europeans. Many of the differences between ethnic groups were attenuated when nutrient consumption was expressed as their percentage contribution to total energy intake suggesting that total food consumption was the major determinant of ethnic differences in nutrient intakes.

Conclusions: There were substantial differences in dietary habits, food selections and cooking practices between European, Māori, Pacific and Asian participants. However, the observed differences were in the area of serving sizes and frequency of consumption of certain foods than to major differences in the range of foods and nutrients consumed or the percentage contribution of carbohydrate, fat or protein to total energy intake.

Implications: The development of strategies to reduce serving sizes and the frequency of consumption of certain foods will be required to help address the major nutrition-related health problems in New Zealand.

Nutrition-related risk factors cause heart disease, diabetes, stroke, cancer and other major health problems.1 The mortality burden caused by poor nutrition habits has been quantified for total blood cholesterol, systolic blood pressure, body mass index and vegetable and fruit intakes. It was estimated that as many as 11,000 deaths in 1997 (40% of all deaths) may have been attributable to the joint effects of sub-optimal diet and physical activity levels.1

Previous surveys that have reported the dietary intakes of adults in New Zealand include the 1977 National Diet survey (NDS),2 the 1989 Life in New Zealand survey (LINZ),3 the 1988-1990 Workforce Diabetes survey (WDS),4 and the 1997 National Nutrition survey (NNS).5 The 1977 survey showed that the typical New Zealand diet were high in total energy intakes, fat, cholesterol, protein and sucrose, but calcium intakes in Māori were lower than in Europeans.2 The 1987 LINZ reported that Māori were higher consumers of doughboy (dumpling), Māori bread (an oven baked potato bread), shellfish and seafood, mutton flaps (sheep belly flaps high in saturated fat) and brisket compared to other New Zealanders.3 The 1988-1990 WDS found higher total energy intakes in Māori women and Pacific men and women, and that Māori and Pacific men and women consumed less carbohydrate, fibre and calcium and more protein, fat, saturated fat and cholesterol than European men and women, respectively.4 The 1997 NNS reported higher total energy intakes, saturated fat and cholesterol in Māori females compared to NZ European and Others, higher saturated fat intakes in males than in females and that Māori men had the highest alcohol intakes.5 This latter survey did not recruit sufficient Pacific people to enable comparisons with Māori or other New Zealanders.

We compare dietary intakes and food group servings of Māori, Pacific, Asian and European adult men and women living in Auckland to determine whether there are major ethnic variations.

Methods

The Auckland Diabetes, Heart and Health Survey was undertaken between December 2001 and November 2003. Adults aged 35 to 74 years were recruited from two sampling frames: one, a cluster sample with random starting point addresses obtained from Statistics New Zealand with probability of selection proportional to the number of people living in that mesh block (response rate 61.3%); and the other, a random sample taken from the November 2000 Auckland electoral rolls stratified into five year age bands that included all people living in the Auckland area (response rate 60%), excluding Franklin and Rodney from both samples which are satellite regions on the outskirts of Greater Auckland. Out of the 4,049 participants interviewed, 1,408 were from the cluster sample and 2,641 were from the electoral roll. Twenty-nine people were excluded as they were outside the age range leaving 4,020. A further 13 people did not complete the food frequency questionnaire leaving 4,007. These participants comprised 47.8% males and 52.2% females; 43.5% Europeans, 25.0% Māori, 24.6% Pacific and 6.9% Asian people. The two separate sampling frames were chosen in order to examine whether either sampling frame had an advantage over the other in terms of recruiting Māori and Pacific people. Ethical Committee approval was obtained from the Auckland Ethics Committees.

Interviews were carried out in halls or clinics close to participant's homes. Personnel were trained in checking for errors and omissions in the questionnaires and in taking blood pressure and other measurements. Ethnicity was defined according to the NZ census.6

Food intake over the previous three months was estimated by a 142-item food frequency questionnaire (FFQ) that included foods favoured by Māori and Pacific Island people (e.g. mutton flaps (sheep belly flaps), povi masima (salty corned beef), shellfish (pipis, mussels, oysters), coconut cream, green bananas, puha (a nutrient rich green that grows wild), kumara (sweet potato), yam, taro tuber, and Māori bread (an oven baked potato bread)). The FFQ was filled in by participants at their home and checked for errors and omissions at their interview the following morning. Serving sizes of vegetables, meat, fish and cake were assessed using colour photographs of foods that participants used to rank themselves into three portion size groups (more, same, less). These were scaled as less 0.5, same 1.0, and more 1.6. Otherwise pre-portioned serving sizes, such as the average weight of a piece of fruit, or slice of bread were used or published serve sizes.7 The comprehensive version of the food composition tables8 was used to calculate nutrient intakes. We have previously reported that this FFQ was valid and reproducible in European, Māori and Pacific Islands participants.9

Resting metabolic rate, the total minimum activity of all tissue cells of the body under steady state conditions, is expressed as the rate of heat production or oxygen consumption related to some unit of body size.10 Resting metabolic rate (RMR) was calculated using the standard equations of Schofield:11

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Minimal requirements for the ratio of total energy intake (in MJ) to resting metabolic rate (EI/RMR) is 1.55 by WHO criteria and 1.38 according to Goldberg et al.12 and can be used as a guide for under-reporting of food intake.

Participant data were weighted according to the sampling frame that they were obtained from and means and standard errors calculated using dual frame sampling methodology13–16 and SAS survey procedures.17 Because of the positively skewed frequency distribution of nutrient intakes, these were converted to loge for calculations; the results presented are geometric means (the exponential of the log-transformed data) and associated 95% confidence interval. As food servings were approximately normally distributed after adjusting for total energy intakes, these are presented as means and standard errors. A two-tailed p-value of <0.01 was the criterion for statistical significance because of multiple nutrient comparisons.

Results

Table 1 shows geometric mean dietary nutrients and the ratio of energy intake to resting metabolic rate (EI/RMR) in men and women by ethnicity after adjusting for age. Māori and Pacific men and women consumed more protein, mono-unsaturated fat (MUFA) and cholesterol, but less alcohol than European men and women, respectively. Māori women also had higher total energy intakes and consumed more carbohydrate, starch, total fat, saturated fatty acids (SFA), and polyunsaturated fatty acids (PUFA) than European women. Pacific men and women had higher total energy intakes and consumed more carbohydrates, starch, total fat and SFA than European men and women, respectively. Pacific women consumed more PUFA and sucrose than European women and Pacific men had lower intakes of calcium than European men.

Table 1.  Geometrie mean (95% confidence interval) daily nutrient intakes and mean ratio of energy to resting metabolic rate (EI/RMR) (se) for men and women adjusted for age. Māori, Pacific and Asian men and women are compared with European men and women, respectively.
 MenWomen
 EuropeanMāoriPacificAsianEuropeanMāoriPacificAsian
  1. Notes:

  2. (a) 0.001<p<0.01.

  3. (c) 0.001<p<0.01.

  4. (b) p<0.001 versus Europeans.

  5. (d) p<0.001 versus Maori.

  6. SFA = saturated fatty acids, PUFA = polyunsaturated fatty acids, MUFA = monounsaturated fatty acids.

Number860441478136882562508140
Energy (MJ)9.810.611.1b9.28.59.6a10.3b8.6
 (9.6,10.1)(9.9,11.3)(10.4,11.9)(8.3,10.1)(8.3,8.8)(9.0,10.2)(9.7,11.0)(8.0,9.3)
EI/RMR [mean(se)]1.34 (0.02)1.45 (0.06)1.48 (0.07)1.42 (0.08)1.53 (0.02)1.69 (0.06)1.71 (0.06)a1.68 (0.08)
Carbohydrate (g)284300314a263257282b311b255
 (276.8,292.2)(280.1,321.5)(293.8,335.9)(240.0,287.9)(249.5,265.4)(263.2,302.0)(289.8,333.2)(235.2,276.3)
Starch (g)139153162b139113136b154b127a
 (135.6,143.4)(142.1,164.6)(152.4,171.2)(127.0,151.7)(109.3,116.2)(125.1,147.5)(144.5,164.1)(116.9,139.0)
Sucrose (g)6061664958586344a,c
 (57.5,63.1)(54.8,67.6)(58.8,73.4)(41.3,57.5)(54.7,60.9)(52.3,63.9)(56.1,70.6)(36.3,52.3)
Fibre (g)26242621b262628c22b,c
 (24.8,26.4)(22.7,26.1)(23.6,27.8)(19.0,23.6)(25.5,27.3)(24.3,27.9)(25.9,31.2)(19.5,24.0)
Protein (g)91101a116b,c1028190b108b,d95a
 (88.9,93.2)(94.5,108.2)(107.4,124.3)(90.5,115.4)(78.9,82.6)(84.9,95.4)(100.8,115.6)(85.3,106.2)
Total Fat (g)8999105b81c7689b93b74c
 (86.6,91.7)(91.5,106.6)(97.5,114.1)(71.9,91.8)(73.5,77.9)(83.0,94.9)(86.1,99.4)(66.3,81.9)
SFA (g)343842b32c2933b36b27c
 (33.1,35.2)(35.0,41.7)(38.2,45.4)(27.4,35.2)(27.6,29.4)(30.5,35.5)(33.5,38.9)(24.6,30.7)
PUFA (g)13.214.214.711.1a,d11.113.7b13.7b10.6d
 (12.8,13.7)(13.2,15.2)(13.6,15.9)(9.6,12.5)(10.8,11.5)(12.9,14.7)(12.8,14.8)(9.4,12.0)
MUFA (g)31.334.535.9a29.227.131.6b31.3a26.5
 (30.4,32.2)(32.1,37.2)(33.1,38.9)(25.7,33.3)(26.3,28.0)(29.5,33.8)(28.9,33.8)(23.6,29.8)
Cholesterol (mg)325405b470b,c474b267333b384b427b
 (314,335)(377,435)(433,510)(392,571)(258,275)(310,357)(345,427)(353,514)
Alcohol (g)7.34.5b1.6b,d2.3b,d3.21.8b0.4b,d0.6b,d
 (6.6,8.0)(3.6,5.6)(1.3,1.9)(1.7,3.1)(2.9,3.5)(1.5,2.2)(0.3,0.5)(0.4,0.8)
Calcium (mg)867849730b724a835796800681b
 (841,892)(780,924)(669,795)(646,811)(809,861)(743,852)(741,863)(620,748)

Asian men and women consumed more dietary cholesterol and less fibre, calcium and alcohol than European men and women, respectively. Asian women also consumed more starch and protein and less sucrose than European women and Asian men consumed less PUFA than European men.

Compared to Māori men and women, Pacific men and women consumed more protein and less alcohol. Pacific men had higher cholesterol intakes compared to Māori men. Asian men and women consumed less total fat, SFA, PUFA and alcohol compared to Māori men and women and Asian women consumed less sucrose, fibre and calcium than Māori women.

Table 1 also shows that the mean EI/RMR's were lower in men than women and lowest in Europeans compared to the other ethnic groups. The mean EI/RMR was significantly higher in Pacific women compared to European women.

Nutrients expressed in relation to total energy intakes (Table 2) showed that Māori, Pacific and Asian men and women had lower intakes of fibre and calcium and percentage contribution of alcohol to total energy intakes and higher intakes of cholesterol in relation to total energy intakes than European men and women, respectively. Asian men and women and Māori and Pacific women had higher intakes of starch compared to European men and women, respectively. Pacific and Asian men and women had higher intakes of protein than European men and women. Pacific men and Māori women had higher total fat intakes and Pacific men higher SFA, Māori women higher PUFA, Asian women lower sucrose intakes and Asian men lower intakes of PUFA, compared to European men and women, respectively.

Table 2.  Geometrie mean (95% confidence interval) nutrient intakes expressed as a percentage contribution or in relation to total energy adjusted for age. Māori, Pacific and Asian men and women are compared with European men and women, respectively.
 MenWomen
 EuropeanMāoriPacificAsianEuropeanMāoriPacificAsian
  1. Notes:

  2. (a) 0.001<p< 0.01

  3. (c) 0.001 <p<0.01

  4. (b) p<0.001 versus Europeans.

  5. (d) p<0.001 versus Maori

  6. SFA = saturated fatty acids, PUFA = polyunsaturated fatty acids, MUFA = monounsaturated fatty acids.

Number860441478136882562508140
Carbohydrate (%)49.248.148.148.751.250.151.350.4
 (48.7,49.8)(47.2,49.0)(47.0,49.3)(46.8,50.8)(50.5,51.9)(49.0,51.3)(50.0,52.5)(48.0,52.9)
Starch (%)24.124.524.825.7a22.424.2a25.4b25.2b
 (23.7,24.5)(23.7,25.3)(23.8,25.8)(24.6,26.9)(21.9,22.9)(23.1,25.2)(24.3,26.6)(23.8,26.7)
Sucrose (%)10.49.810.19.011.510.3a10.48.6b
 (10.1,10.8)(9.0,10.5)(9.3,10.9)(7.8,10.4)(11.0,11.9)(9.6,11.0)(9.5,11.3)(7.3,10.2)
Fibre (g/MJ)2.62.3b2.3a2.3a3.12.7b2.8a2.5b
 (2.5,2.7)(2.2,2.4)(2.2,2.5)(2.1,2.5)(3.0,3.2)(2.6,2.8)(2.6,3.0)(2.3,2.8)
Protein (%)14.815.2b,d16.7b,d17.815.115.116.8b,d17.7b,d
 (14.6,15.0)(14.9,15.6)(16.2,17.1)(16.8,18.9)(14.9,15.4)(14.6,15.5)(16.3,17.3)(16.5,19.0)
Total Fat (%)33.634.435.2a32.832.734.4b33.231.7
 (33.2,34.0)(33.6,35.3)(34.2,36.2)(31.4,34.3)(32.2,33.3)(33.6,35.1)(32.2,34.3)(29.8,33.8)
SFA (%)12.913.313.9b12.512.312.713.011.8
 (12.7,13.1)(12.9,13.8)(13.4,14.5)(11.9,13.2)(12.1,12.6)(12.3,13.2)(12.5,13.5)(11.0,12.7)
PUFA (%)5.04.94.94.4a,c4.85.3b5.3b,c4.6c
 (4.9,5.1)(4.7,5.2)(4.7,5.1)(4.1,4.8)(4.7,4.9)(5.1,5.5)(4.7,5.1)(4.2,5.0)
MUFA (%)11.912.012.011.811.712.211.2d11.4
 (11.6,12.0)(11.7,12.4)(11.6,12.4)(11.2,12.5)(11.5,12.0)(11.9,12.6)(10.8,11.7)(10.6,12.3)
Cholesterol (mg/MJ)33.138.2b42.4b,c51.7b,d31.234.9b37.3b49.6b,d
 (32.2,33.9)(36.6,39.9)(40.4,44.5)(44.9,59.2)(30.3,32.1)(33.0,36.9)(34.6,40.2)(42.4,58.0)
Alcohol (%)2.61.60.6b,d0.9b,c1.40.8b0.2b,d0.3b,d
 (2.4,2.8)(1.3,2.0)(0.5,0.7)(0.7,1.2)(1.2,1.5)(0.6,1.0)(0.1,0.3)(0.2,0.4)
Calcium (mg/MJ)88.280.0b65.8b,d79.0b97.883.2b77.6b79.2b
 (86.5,90.0)(76.8,83.4)(63.0,68.6)(74.7,83.5)(95.7,99.7)(80.2,86.4)(74.4,81.0)(74.5,84.3)

Compared to Māori men and women, Pacific and Asian men and women had higher protein and cholesterol intakes and lower alcohol intakes. Pacific men had lower calcium intakes than Māori men. Compared to Māori men and women, Pacific and Asian men and women had higher protein and lower alcohol intakes. Pacific men and women had lower calcium intakes than Māori men and women, respectively. Asian women had lower sucrose and PUFA intakes than Māori women, and Asian men had lower fat intakes than Māori men.

Mean energy and age-adjusted serves per month of major food groups are shown in Table 3. Compared to European men and women, Māori, Pacific and Asian men and women had fewer servings of cheese; Māori, Pacific and Asianmen and women hadmore servings of fish; Pacific and Asian men and women had more servings of chicken; Māori men and women and Asian women had fewer servings of vegetables; Māori men and women had fewer servings of fruit; Pacific and Asian men and women had fewer cups of milk and servings of breakfast cereal; Māori and Pacific men and women had more slices of bread; Māori men and women and Pacific men had more servings of eggs; Asian men and women had fewer slices of bread; Asian men and women had fewer servings of red meat, respectively. The proportions of Māori men and women, and Asian women who reported three or more servings of vegetables per day were lower than European men and women, respectively. Māori men and women and Māori, Pacific and Asian women also had lower proportions who consumed two or more servings of fruit each day compared to European men and women, respectively.

Table 3.  Mean serves (se) per month (adjusted for energy and age) of major foods eaten. Māori, Pacific and Asian men and women are compared with European men and women, respectively.
 MenWomen
 EuropeanMāoriPacificAsianEuropeanMāoriPacificAsian
  1. Notes:

  2. (a) 0.001<p< 0.01

  3. (1) Serves of vegetables per day

  4. (b) p<0.001 versus Europeans

  5. (2) Serves of fruit per day

  6. (c) 0.001<p< 0.01

  7. (3) Excludes low fat cheese

  8. (d) p<0.001 versus Māori

Number860441478136882562508140
Red meat31.9 (0.53)30.7 (1.24)37.8 (2.34)c26.3 (1.90)a28.5 (0.57)30.5 (1.16)30.1 (1.26)21.7 (1.78)b,d
Chicken4.9 (0.15)5.5 (0.35)12.4 (0.83)b,d8.5 (0.76)b,d5.7 (0.17)6.0 (0.29)11.1 (0.59)b,d9.0 (0.74)b,d
Fish8.2 (0.23)10.0 (0.59)a17.9 (0.95)b,d12.1 (1.24)a9.3 (0.31)11.6 (0.71)a19.4 (1.25)b,d13.9 (1.26)b
Vegetables121.7 (1.03)100.7 (1.06)b110.1 (1.08)118.8 (1.12)c151.9 (1.03)132.7 (1.06)b138.2 (1.13)126.1 (1.12)a
≥ 3 serves/day1 (%)75.8 (1.59)67.6 (2.95)a68.4 (3.58)68.2 (3.58)86.6 (1.28)79.9 (2.55)a79.3 (3.77)72.7 (4.54)b
Fruit59.7 (1.59)47.3 (3.54)a62.2 (7.69)73.0 (5.03)d94.1 (2.71)72.1 (4.53)b87.4 (5.87)86.2 (5.55)
≥ 2 serves/day2 (%)40.7 (1.81)27.2 (3.15)b35.1 (4.04)41.2 (5.20)56.8 (1.81)42.0 (3.08)b44.5 (3.82)b41.2 (5.20)a
Eggs (number)11.0 (0.36)16.6 (1.16)b17.8 (1.16)b15.5 (1.34)a9.2 (0.35)12.7 (0.99)b14.5 (1.36)b14.2 (1.40)b
Cheese314.0 (0.51)8.0 (0.98)b2.6 (0.59)b,d4.6 (0.74)b,c15.5 (0.50)8.7 (0.62)b3.9 (0.65)b,d5.0 (0.90)b,d
Milk (cups per month)65.3 (1.12)60.7 (1.25)24.3 (1.24)b,d25.5 (1.31)b,d57.5 (1.12)44.5 (1.24)39.7 (1.24)a28.9 (1.37)b
Bread (slices)24.5 (0.48)30.5 (1.58)b32.6 (1.69)b19.1 (1.49)b,d19.5 (0.46)26.9 (0.95)b30.6 (1.20)b16.5 (1.26)d
Breakfast Cereal15.8 (0.48)15.5 (2.81)5.0 (0.67)b,d6.4 (1.03)b,c17.4 (0.78)14.9 (1.07)10.0 (0.87)b,d9.4 (1.63)b,c

Compared to Māori men and women, Pacific and Asian men and women had fewer servings of cheese and breakfast cereal; Pacific and Asian men and women had more servings of chicken; Pacific men and women had more servings of fish; Asian men and women had fewer servings of red meat, fruit and bread and Asian men had more servings of vegetables and fewer servings of bread and cups of milk per month.

There were significant ethnic differences in the type of milk consumed (p<0.001), with 73.8% of Pacific, 63.0% of Asians, 58.6% of Māori and 38.9% of Europeans drinking whole or homogenised milk. Low-fat milks were favoured by 57.8% of Europeans, 36.9% of Māori, 30.8% of Asians and 22.2% of Pacific people. Between 3.3 and 6.2 per cent of each ethnic group did not consume milk.

Discretionary use of salt also differed significantly (p<0.001) among ethnic groups with 41.4% of Māori, 31.5% of Pacific, 23.7% of Europeans and 19.1% of Asians usually adding salt to their meals, whereas 48.7% of Asians, 47.1% of Europeans, 27.8% of Māori and 18.7% of Pacific people rarely or never added salt to their meals. Butter use as a spread was slightly higher in Pacific people (25.5%), Māori (22.5%) and Asians (24.3%) compared to Europeans (18.8%), although margarine use as a spread was higher in Māori (58.7%), Europeans (56.6%) and Pacific people (52.9%) compared to Asians (38.9%). Neither butter nor margarine were used as a spread by 27.7% of Asians, 17.8% of Europeans, 8.6% of Māori and 4.0% of Pacific people (p< 0.001).

Usual methods of cooking meats and vegetables are shown in Table 4. The most common meat cooking method was by frying or roasting for Asians, Europeans and Māori, whereas Pacific people preferred to boil meat. Grilling meat was preferred by Māori and Europeans, compared to Asians and Pacific people. Most Pacific, Māori and Europeans usually boiled or steamed vegetables, whereas approximately one half of Asians usually boiled or steamed vegetables and approximately one third usually fried or roasted them.

Table 4.  Usual cooking practices in per cent by ethnicity.
Cooking PracticeEuropeanMāoriPacificAsian
  1. Note:

  2. All overall p-values are statistically significant (p<0.001).

Fry or roast meat33.933.822.243.6
Boil meat in water3.111.643.524.9
Grill meat31.732.710.712.1
Fry or roast vegetables4.15.97.236.1
Boil or steam vegetables67.776.981.648.0
Fry meat and vegetables in vegetable oils81.375.973.697.7
Fry meat and vegetables in butter, lard or dripping4.28.712.90.0
Roast meat and vegetables in vegetable oils52.943.541.669.7
Dry roast meat and vegetables39.448.347.321.7

There were also differences between ethnic groups in fat use for frying meat and vegetables. Meat and vegetables were usually fried in vegetable oil by Asians, followed by Europeans, Māori and Pacific people. Higher proportions of Pacific and Māori used animal fats such as butter, lard or dripping for frying meat and vegetables compared to Europeans, whereas no Asians used animal fats for frying meat or vegetables. More Asians and Europeans used vegetable oils to roast meat and vegetables, whereas more Māori and Pacific people dry roasted meat and vegetables. Higher proportions of Māori (27.3%), Pacific (15.7%) and Europeans (14.6%) ate all or most of the fat on meat compared with Asians (6.8%).

Higher proportions of Māori and Pacific ate larger than the standard portions of chicken, fish and red meat than Europeans and Asians (Table 5). More Europeans and Māori ate larger portions of cheese than Pacific people and Asians. Higher proportions of Māori and Pacific people ate larger portions of potato, kumara or taro than Europeans and Asians. However, larger portions of other vegetables were eaten by more Pacific and Asians than Māori and Europeans. A higher percentage of Māori had larger portions of cake or dessert than the other ethnic groups.

Table 5.  Percentages eating larger than the standard serving size by ethnicity.
FoodEuropeanMāoriPacificAsian
Chicken16.826.335.314.2
Fish37.242.553.717.5
Red meat15.425.228.59.2
Cheese32.328.918.95.3
Potato, kumara or taro33.339.347.412.6
Other vegetables32.336.450.139.7
Cakes or desserts10.921.315.48.7

Discussion

The ethnic differences in nutrient intakes in Māori men and women compared to European men and women were consistent with their lower intakes of fruit, vegetables and cheese and higher intakes of eggs and bread. A higher percentage contribution, or in relation, to total fat and cholesterol to total energy intakes and lower fibre and calcium intakes were also reported by the NNS.5 However, they reported higher alcohol intakes from a 24-hour dietary recall in Māori men.5

The ethnic differences in nutrient intakes observed in Pacific men and women compared to European men and women were consistent with their higher consumption of chicken, fish and bread and lower consumption of cheese, milk and breakfast cereal. Similar results were observed in a working population, with the exception of starch (which was not significantly different) in Pacific women compared to European women.4

Asian people consumed red meat, cheese, milk, bread and breakfast cereal less often and servings of chicken more often compared to Europeans. The diets of Asian people living in New Zealand do not appear to have been described previously. However, the 1995 Australian National Nutrition Survey also reported lower consumption of bread, breakfast cereal and milk and lower intakes of calcium in East Asians compared to other Australians.18

Compared to the 1988-1990 WDS, nutrients expressed as their contribution to total energy intakes using the same FFQ,4 the current survey shows slightly higher carbohydrate and sucrose intakes, approximately equal protein intakes, lower total fat and SFA intakes, higher PUFA and MUFA intakes and higher calcium intakes in relation to total energy intakes. Similarly, compared to the WDS, the servings of meat, chicken, fruit, eggs, cheese and breakfast cereal per month were lower.

Fat intakes

The percentage contribution to total energy intakes from fat declined from 37.5% to 35% in New Zealand adults between 1989 and 1997.5 The NNS reported a significant difference in the percentage contribution of fat to total energy intakes of 36% for Māori females and 34% for non-Māori females. However, the NNS found no significant difference by ethnicity for males with 37% in Māori and 35% in non-Māori.5 The NNS also reported that 15% of total energy intake was from SFA, 5% as PUFA, and 12% as MUFA.5Table 2 shows similar results, however, there may be a suggestion of slightly lower total fat and SFA intakes. Recent WHO guidelines recommend 15-30% of total energy be consumed as fat.19

Māori, Pacific, and Asian men and women had significantly higher dietary cholesterol intakes (Tables 1 and 2) compared to European men and women, respectively.

The NNS reported median daily intakes of dietary cholesterol of 359mg in males and 243mg in females from a 24-hour recall.5 Dietary cholesterol intakes in this study were slightly lower for European men only, but these differences may be due to the different methods of dietary assessment. However, dietary cholesterol intakes of European, Māori and Pacific men and women were similar to those reported from the WDS.4 The major sources of dietary cholesterol are meat, eggs and dairy products. Māori men and women and Pacific men consumed more eggs per month than Europeans and Asians (Table 3) and higher proportions of Māori and Pacific ate all or most of the fat on meat than Europeans. This was consistent with the higher proportions of Māori and Pacific people who reported never or occasionally trimming excess fat from their meat in the NNS.5

Fruit and vegetable intakes

The WHO has recommended that adults consume at least five servings of vegetables and fruit per day to reduce the risk of cardiovascular disease and some cancers.20 Data from the NNS that used a single 24-hour dietary recall, estimated that only 40-46% of adults were achieving adequate fruit and vegetable intakes.21 A re-analysis of the NNS reported that Māori had slightly lower mean vegetable and fruit intakes compared with non-Māori,1,7 which is consistent with this study.

The NZ Ministry of Health has recommended that adults eat at least three servings of vegetables and at least two servings of fruit each day7 Using this definition, the 2002/03 NZHS reported that European and Māori males were significantly more likely than Pacific and Asian males to eat three ormore servings of vegetables each day, that European females were more likely than all other ethnic groups and Māori females were more likely than Pacific and Asian females to eat three or more servings of vegetables each day22 This is in contrast to this survey where Māori men and women and Asian women ate significantly less servings of vegetables each day.

On the other hand, Pacific men were more likely than European and Māori men and European females were more likely than Māori females to eat two or more servings of fruit each day22 Māori men were less likely than European men and Māori, Pacific and Asian women were all less likely to eat two or more servings of fruit each day than European women (Table 3). The finding of less servings of vegetables per month in Asian women has been reported previously23 However, the NZHS also reported that Asian people had similar fruit and vegetable intakes to Māori and Pacific, but lower intakes than Europeans,22 which was not found in this study in Pacific people (Table 3). A possible explanation for the differences in fruit and vegetable servings between the ethnic groups may be related to socio-economic status.

Salt

This study found ethnic differences in usually adding salt to meals at the table after cooking. A reduction in sodium (principally salt) intakes has been found to reduce systolic blood pressure.24 Māori and Pacific people have been shown previously to have higher systolic and diastolic blood pressure levels.25,26 Although about 75% of sodium intake comes from salt added to food during its manufacturing and processing, about 15% is provided by salt added while cooking or added at the table.27 Bread is the leading source of sodium in the New Zealand diet, followed by processed meats, sauces, breakfast cereals, cakes, muffins and biscuits, bread-based dishes, butter and margarine.1 Therefore, the higher bread intakes in Māori and Pacific people will be contributing to this sodium load, together with the higher breakfast cereal intakes in Māori men and women compared to Pacific and Asian men and women.

Calcium

Lower calcium intakes in relation to total energy intakes were observed in Māori, Pacific and Asian men and women (Table 2) which is reflected by their lower serves of cheese per month and by the lower number of cups of milk drunk per month in Pacific and Asian men and women (Table 3). The NNS reported that almost half of the NZ population's calcium intake was derived from these two sources.5 The NNS also reported that Pacific people were less frequent consumers of cheese.5 The findings of higher bread and lower breakfast cereal intakes in Māori and Pacific people was also observed in the NNS.5

Cooking practices

A higher proportion of Pacific and Māori people used animal fats such as butter, lard or dripping for frying meat and vegetables compared to Europeans. Māori were less likely to use olive/canola oil in cooking meat and chicken compared with NZ Europeans and Others in the NNS.5 Similarly, Pacific women were more likely to have used margarine and less likely to have used lard in cooking meat or chicken than NZ Europeans and Others.5

Strengths and limitations

The major strengths of this study are its size and its community-based sample. A limitation of the FFQ is that participants are required to estimate their usual daily or weekly consumption of foods rather than measuring ‘actual’ dietary intakes.28 A further limitation is that the FFQ has not been validated in Asian people.9 It is also possible that some participants may over- or underestimate the frequency of food intakes. Compared to the cut-off level of 1.38 for the EI/RMR,12 European men and women and Asian men may be systematically underestimating frequencies of intakes (Table 1). On the other hand, Pacific women were least likely to underestimate dietary intakes. However, this effect of over-and underestimation of energy intake on ethnic comparisons of nutrient intakes is minimised by expressing nutrient intakes as their percentage contribution to total energy intakes (Table 2) and making group comparisons.28 Furthermore, nutrient intakes were broadly similar to the most recent NNS.5

It is not possible to determine whether the ethnic differences reported would apply to all regions in New Zealand, as there have been insufficient Māori or Pacific people in previous national studies to report food intake by region.

Conclusions

There were differences in dietary habits, food selections and cooking practices between European, Māori, Pacific and Asian participants. Ethnic differences were in the area of larger serving sizes in Māori and Pacific people and increased frequency of eating some food groups and less of others. The development of strategies to reduce serving sizes and the frequency of consumption of certain foods will be required to help address the major nutrition-related health problems in New Zealand.

Acknowledgments

This survey was funded by the Health Research Council of New Zealand. We thank the technical and clerical staff who conducted the study so capably and efficiently. We gratefully acknowledge the Ministry of Health (Public Intelligence) and Crop and Food Research for providing a complimentary copy of FOODfiles to assist with dietary assessment.

Ancillary