Prenatal consumption of apples, fish shown to prevent asthma in children

The children of pregnant women who consumed more apples and fish had significantly lower rates of asthma and eczema at age five than the children of mothers who had consumed less, according to a new study conducted at the University of Aberdeen in Scotland and presented at the American Thoracic Society's 2007 International Conference.

Researchers studied 1,212 children whose mothers had filled out questionnaires about their food consumption during pregnancy. Once the children were five years old, the researchers also had the mothers fill out a questionnaire about their children's diet, allergies and respiratory symptoms.

The researchers found that children whose mothers had eaten the most apples while pregnant had lower rates of asthma and were less likely to have ever wheezed than children whose mothers had eaten the least amount of apples. Children whose mothers had eaten fish once or more a week while pregnant were less likely to have eczema than children whose mothers had not eaten fish at all.

While previous studies have found similar protective effects from fruit juice, citrus fruit, kiwi fruit, vegetables or foods made with whole grains, the current study found no such correlation. According to researcher Saskia Willers, of Utrecht University in the Netherlands, this may arise from the different approach of the Aberdeen study.

"Other studies have looked at individual nutrients' effect on asthma in pregnancy, but our study looked at specific foods during pregnancy and the subsequent development of childhood asthma and allergies, which is quite new," Willers said. "Foods contain mixtures of nutrients that may contribute more than the sum of their parts."

However, the researchers speculated that some of the protective effects may come from flavonoids in apples and omega-3 fatty acids in fish. Further studies are required, they said, to see if this effect extends later into childhood or adulthood.