The association between fruit and vegetable intake and the odds of asthma among children and adolescents

BACKGROUND: Previous epidemiological studies on the correlation between fruit and vegetable consumption and asthma, the majority of them were conducted in developed countries, have led to conflicting results. This study aimed to examine the relationship between fruit and vegetable intake and the risk of asthma among a large sample of children and adolescents. METHODS: This cross-sectional study was conducted as part of the Global Asthma Network (GAN) on 7667 Iranian children and adolescents. Asthma and its related outcomes were measured using validated questionnaires. A food frequency method was used to assess the dietary intake. The association between fruit and vegetable intake and asthma and its related symptoms was examined using logistic regression. RESULTS: After adjustment for all possible confounding variables, no significant association was found between fruit and vegetable intake and the odds of medication use for asthma and asthma confirmed by a doctor. However, an inverse significant trend was found between fruits intake and current asthma. After adjusting for age, sex, BMI, and the use of television and computers, participants who regularly consumed fruit had a 37% lower likelihood of experiencing wheezing in the past 12 months (OR = 0.63; 95% CI: 0.42-0.94, P trend = 0.001) compared to those who never or only occasionally consumed fruit. Additionally, individuals who reported consuming vegetables most or all days had a 38% reduced chance of wheezing in the past 12 months (OR = 0.62; 95% CI: 0.48-0.80, P trend < 0.001) compared to participants with infrequent vegetable intake. Participants with regular fruit and vegetable intake combined (OR = 0.50; 95% CI: 0.31-0.82, P trend < 0.001) had a 50% lower likelihood of wheezing in the past 12 months in comparison with those who never or only occasionally fruits and vegetables combined consumers. CONCLUSION: Our findings suggest that regular consumption of fruits and vegetables on most or all days has a protective effect against wheezing in the past 12 months. Future longitudinal studies should be conducted to confirm our findings.