By Robert Preidt
For the study, researchers examined data from a 2005 to 2007 survey of 4,900 pregnant women who were part of a U.S. Food and Drug Administration and Centers for Disease Control and Prevention study.
Nearly 3 percent of the women said they restricted certain foods during pregnancy in the belief that it would prevent future food allergies in their children. That included 1.7 percent who ate fewer nuts, 0.3 percent who ate fewer eggs, and 0.04 percent who ate less dairy.
"At the time the survey was conducted, few pregnant women in this large data set said they gave up certain foods with the express aim of avoiding a food allergy in their babies," said study leader Dr. Karen Robbins. She is an allergist at Children's National Health System in Washington, D.C.
"However, mothers who had an older child with a food allergy or who had food allergies themselves had significantly higher odds of trying this food avoidance strategy," Robbins said in a hospital news release.
Compared to other infants, those born to mothers who made such diet changes during pregnancy were twice as likely to have problems with food at age 4 months, but not at ages 9 months or 12 months, the findings showed.
There were no differences in food allergy diagnosis rates between the two groups of infants, according to a report presented recently at the American College of Asthma, Allergy and Immunology meeting in Seattle.
Research presented at meetings is typically considered preliminary until it is published in a peer-reviewed journal.
Robbins said researchers want to know more about how often pregnant women with a family history of allergies avoid foods in hopes of preventing allergies in their offspring.
"We hope to learn what factors into these women's decision-making as well as why many of them settled on food avoidance as a potential strategy to try to prevent food allergy in their infants," she said.
Millions of Americans suffer a food allergy each year, according to the FDA. Reactions can range from mild to life-threatening.
Some of the most common allergenic foods are milk, eggs, fish, shellfish, tree nuts, peanuts, wheat and soybeans.