Fruit and vegetable intakes and asthma in the E3N study.

BACKGROUND: A study was undertaken to investigate whether dietary intake predicted the prevalence of adult asthma among French women participating in the E3N study. METHODS: Of 68 535 women who completed a food frequency questionnaire in 1993 which included 238 food items, 2145 (3.1%) reported having asthma. The distribution of food intake was divided into quartiles (Q(1)-Q(4)) and the prevalence of asthma was compared between the different quartiles (lowest as reference) using logistic regression models on cross sectional data. RESULTS: After adjusting for age, body mass index, menopausal status, smoking status, total caloric intake, physical activity, and use of dietary supplements, women who had a greater intake of tomatoes (OR(Q1-Q4) 0.85 95% CI 0.75 to 0.96, test for trend p = 0.02), carrots (OR(Q1-Q4) 0.81 95% CI 0.72 to 0.92, test for trend p = 0.0003), and leafy vegetables (OR(Q1-Q4) 0.82 95% CI 0.73 to 0.93, test for trend p = 0.0009) had a lower prevalence of asthma. Apples were marginally related to the prevalence of asthma. No other fruits or vegetables were significantly associated with asthma prevalence. CONCLUSIONS: These results suggest that the intake of some vegetables may decrease the prevalence of adult asthma.

Body mass index, change in body silhouette, and risk of asthma in the E3N cohort study.

To evaluate the impact of body mass index (BMI) (weight (kg)/height (m)(2)) and change in body silhouette on asthma risk, the authors investigated a cohort of women participating in the E3N Cohort Study in France from 1990 to 1993. The authors identified 372 incident cases of asthma among 67229 women aged 40-65 years at baseline. Data were analyzed using proportional hazard models to determine the risk of asthma incidence in relation to BMI and body silhouette. Reported BMI at baseline was related to the incidence of asthma, with a significantly increased risk corresponding to increasing BMI quintiles (test for trend: p < 0.001). Compared with a BMI of 20-21.4 (second quintile), women with a BMI >or=27 had double the risk of incident asthma after adjustment for potentially confounding factors (multivariate relative risk = 2.02, 95% confidence interval: 1.38, 2.98). Increase in body mass between menarche and the start of the follow-up study was significantly related to asthma risk (for an increase of two silhouettes, relative risk = 1.66, 95% confidence interval: 1.18, 2.32). The authors conclude that a high BMI is significantly related to the risk of asthma incidence and that an increase in body silhouette between menarche and adulthood is related to the incidence of asthma later in life.