Avoiding some foods because of allergies? You may not need to.

RODALE NEWS, EMMAUS, PA—Last weekend at the annual meeting of the American College of Allergy, Asthma and Immunology (ACAAI), a panel of experts previewed new recommendations on food allergies that will be announced in early December by the National Institute of Allergy and Infectious Diseases (NIAID), an arm of the National Institutes of Health. Intended for physicians, the new guidelines are expected to clear up a great deal of confusion among allergists as to how food allergies are defined, diagnosed, and managed.

"The public tends to assume that any problems they have following the consumption of food must be a food allergy, but the data show that 50 to 90 percent of self-reported cases of food allergy turn out not to be a food allergy at all," Matthew Fenton, PhD, with the NIAID's Division of Allergy, Immunology and Transplantation, said at a press conference announcing the new guidelines. "There are several diseases that mimic food allergies," he added, which can make it difficult for allergists and other physicians to adequately treat the problem.

And, according to a new study in the Journal of Pediatrics, assuming that any adverse reaction to food is caused by a food allergy could lead to problems like nutrient deficiencies and malnutrition. After noticing a number of children who came into their clinic with nutrient deficiencies and presumed food allergies, a team of researchers from National Jewish Health in Denver researched the medical histories those who had undergone a type of food allergy testing called an oral food challenge, the most reliable testing method for food allergies. They found that in many cases the children were not truly allergic to more than 90 percent of the foods they were avoiding.

THE DETAILS: The authors analyzed the medical charts of 125 children who had undergone food challenges at the National Jewish Health Pediatric Food Allergy and Eczema Program between 2007 and 2008; a food challenge is a test during which children are exposed repeatedly to allergenic foods and monitored for allergic reactions. The results of the food challenges were compared to foods that the children were avoiding because of results from another form of food allergy testing: either a skin-prick test or an immunoglobulin E (IgE) antibody test, both of which are more common but less-accurate testing methods (previous research has found that they have a less than 50 percent accuracy rate).

Of the foods avoided because a previous IgE or skin-prick test suggested that a child might be allergic, 93 percent produced no allergic reaction. And when the authors looked at foods that children were avoiding because they'd had a previous allergic reaction (like an upset stomach or an eczema flare-up), 84 percent produced no allergic reactions. The most commonly avoided foods in both situations that produced no negative reactions were fruits (with the exception of bananas), vegetables, meat, milk, shellfish, and oats, while eggs, peanut, soy, and wheat were the most common allergenic foods.