The study, published in the journal Thorax, also found that mothers who ate fish more than once a week had children who were 43 percent less likely to have eczema than women who never ate fish.
"This was a good study, but we need a lot more evidence still," said Doshi, who pointed out that the children in the study generally had well-balanced, nutritious diets, and that may have played a role as well.
So, what's a pregnant woman to do? "The general consensus is that women should consume a good, well-balanced diet with lots of fruits and vegetables, and not to overindulge in any one food," he said.
Appleyard recommends avoiding nuts, peanuts and shellfish while you're pregnant to reduce the risk of your child developing a food allergy.
While this advice applies to everyone, it may be even more important for those with a family history of allergies. And Appleyard added that women who are vegetarians have to weigh the risks and benefits of following such dietary restrictions.
She agreed that prenatal nutrition is an area that needs a lot more research but suggested that pregnant women might want to "pick your foods wisely, because what you're eating today may not only nourish your body, but may have an impact on your baby's future health."
Appleyard added that for preventing asthma, avoiding cigarette smoke both before and after birth is crucial.
To learn more about allergies and their causes, visit the U.S. National Heart, Lung, and Blood Institute.
SOURCES: Jennifer Appleyard, M.D., chief, allergy and immunology, St. John Hospital and Medical Ce
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