Scientists found that children who followed a Mediterranean diet had a 30% lower risk of developing hay fever. ... About 30% of children have allergies, of which half should have symptoms. However, in Crete 30% did have allergies but virtually none of them exhibited symptoms, such as asthma, runny nose and itchy eyes. This anomaly is virtually unheard of, said Paul Cullinan, U.K. National Heart and Lung Institute, one of the authors of the study.

Nearly all the children in the study ate fresh tomatoes and several types of fruit at least weekly, while over half of them consumed them daily. Most of the children ate nuts regularly.

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It always comes back to fruits and nuts, doesn't it?