Background The occurrence of asthma may be associated with dietary factors.
Objective To examine the association between nutrient intake and physician-diagnosed asthma and allergic rhinitis.
Methods A stratified, multiple-staged sampling design was used to select study areas, in which household interviews were carried out to gather information on health status and 24-h food recall. Data from 1166 adolescents, 13–17 years of age, were analysed.
Results In univariate analysis, total calorie and energy-adjusted fat intake were associated with the prevalence of asthma, whereas vitamin A and vitamin C intake showed negative association with asthma. Multivariate logistic regression was used to adjust for sex and levels of urbanization; intake of saturated fats was associated with increased risk (OR = 2.02 for an increase of one SD, 95%CI 1.40–2.90), while monounsaturated fats were inversely related to asthma (OR = 0.65 for an increase of one SD, 95%CI 0.43–0.99). Vitamin C intake in the lowest quartile was associated with elevated risk for asthma with marginal significance (OR = 1.81, 95%CI 0.88–3.71, P = 0.10). None of the nutritional factors was associated with allergic rhinitis.
Conclusion Results from this cross-sectional survey suggest that saturated and monounsaturated fats may have different effects on airway inflammation.