Fruit and vegetable consumption in relation to allergy: disease-related modification of consumption?

Previous largely cross-sectional studies suggest that fruit and vegetable consumption reduces the risk of allergic disease in children, but results are conflicting.

To investigate the association between current fruit or vegetable intake and allergic disease in 8-year-old Swedish children, and to evaluate the potential effect of disease-related modification of consumption.

Cross-sectional data were obtained from a Swedish birth cohort study. Information on fruit and vegetable consumption as well as symptoms and diagnoses of allergic diseases was obtained by parental questionnaires at the 8-year follow-up. Allergen-specific IgE levels against food and inhalant allergens were obtained from blood samples collected at age 8 years. In total, 2447 children were included. Data were analyzed with logistic regression.

An inverse relation was observed between total fruit consumption and rhinitis (odds ratio, highest vs lowest quartile, 0.62; 95% CI, 0.45-0.86; P for trend, .002), whereas no association was observed for total vegetable intake. In analyses of individual foods, intake of apples/pears and carrots was inversely associated with rhinitis, asthma, and atopic sensitization. Fifty percent of the children with rhinitis were sensitized against birch pollen, which may cross-react with apples and carrots. After exclusion of children who reported food-related allergic symptoms, most of the observed inverse associations moved toward the null and became nonsignificant.

We confirm the inverse associations between fruit intake and allergic disease in children observed in earlier studies. However, our data also indicate that disease-related modification of consumption contributed to this association.