Protective effect of fruits, vegetables and the mediterranean diet on asthma and allergies among children in crete.

INTRODUCTION: Atopy is not uncommon among children living in rural Crete; but wheeze and rhinitis are rare. We examined whether this discrepancy could be attributed to a high consumption of fresh fruit and vegetables or adherence to a traditional Mediterranean diet.

METHODS: A cross-sectional survey was performed in 690 children aged 7-18 years in rural Crete. Parents completed a questionnaire on the child’s respiratory and allergic symptoms, and a 58-item food frequency questionnaire. Adherence to a Mediterranean diet was measured through a scale on 12 dietary items. Children underwent skin prick tests with 10 common aeroallergens.

RESULTS: 80% of children ate fresh fruit (and 68% vegetables) at least twice a day. The intake of grapes, oranges, apples, and fresh tomatoes – the main local products in Crete – had no association with atopy but was protective for wheezing and rhinitis. High consumption of nuts was found to be inversely associated with wheezing (OR, 0.46; 95% CI, 0.20-0.98), whereas margarine increased the risk of both wheeze (OR, 2.19; 95% CI, 1.01-4.82) and allergic rhinitis (OR, 2.10; 95% CI, 1.31-3.37). A high level of adherence to the Mediterranean diet was protective for allergic rhinitis (OR, 0.34; 95% CI, 0.18-0.64) while a more modest protection was observed for wheezing and atopy.

CONCLUSION: Our data suggest a beneficial effect of commonly consumed fruits, vegetables and nuts, and of a high adherence to a traditional Mediterranean diet during childhood on symptoms of asthma and rhinitis. Diet may explain the relative lack of allergic symptoms in this population.