Women who follow a Mediterranean diet during pregnancy may avert asthmalike symptoms and atopy in their children, results of a population study in the journal Thorax suggest.
Researchers studying a birth cohort of 412 children in Menorca, Spain, found that offspring of mothers who closely followed a Mediterranean diet in pregnancy were less likely to experience persistent wheeze (adjusted odds ratio 0.22), atopic wheeze (OR 0.30), or atopy (OR 0.55) at a 6.5-year follow-up, compared with children of mothers who were less adherent to the diet.
Micronutrients such as antioxidants or polyphenols contained in the fruits, vegetables, legumes, and oils that are key ingredients of the Mediterranean diet may have protective effects against asthma, may protect the airways against oxidative damage, or may have anti-inflammatory effects, wrote Dr. Leda Chatzi of the University of Crete, Heraklion, Greece, and associates (Thorax 2008 Jan. 15 [Epub doi:10.1136/thx.2007.081745]).
Over a 12-month period beginning in mid-1997, the researchers enrolled 507 women seeking antenatal care at general practices in Menorca.
A total of 412 children of the women who were enrolled underwent skin-prick tests for allergies at a 6.5-year follow-up.
In addition, 468 parents completed questionnaires on children's respiratory and allergic symptoms, and supplied information on the mother's diet during pregnancy and the children's diet at 6.5 years using a food frequency questionnaire.
The questionnaires were then scored according to how much of the food intake matched a traditional Mediterranean diet.
A total of 36% of mothers had a low-quality Mediterranean diet in pregnancy; the remainder had a high-quality diet.
Approximately 13% of the children at follow-up had persistent wheeze, 6% had atopic wheeze, and 17% had atopy.
Maternal intake of vegetables more than eight times a week in pregnancy was significantly associated with a reduced risk of persistent wheeze (odds ratio 0.36) and atopy (OR 0.4) in their children, compared with children of mothers who ate fewer servings.
Eating fish two to three times a week and legumes at least once a week during pregnancy each was also significantly associated with a reduced risk of persistent wheeze (OR 0.34 and OR 0.36, respectively).
Although there was a trend toward a high-quality Mediterranean diet in pregnancy having a protective effect against atopic wheeze, the association was not significant, possibly because of the small number of children affected (n = 20), the investigators wrote.
At 6.5 years, 9% of the children had a diet that scored low, 54% scored intermediate and 37% scored high on Mediterranean diet measures.
A high score was protective against persistent wheeze, but the effect was only marginally significant, the researchers said.