Kid’s allergies estimated to be more prevalent than thought

By Dr. Ananya Mandal, MDJun 21 2011

It is found that food allergies in children might be more common than some previous research has suggested. A new study estimates that about 8% of children, about 6 million in the U.S., have a food allergy. Not only is this estimate higher than some previous research has reported, the study found that reported allergic reactions are often severe and that many kids have more than one allergy.

The researchers say that the new estimate is helpful for physicians because researchers couldn’t previously pin down a number -- figures of between 2% and 8% came from studies that were too small or were limited in other ways. In the current study, led by researchers at the Northwestern University Feinberg School of Medicine, parents of more than 38,000 children were surveyed about whether their child had been diagnosed with a food allergy and had one or more of a number of symptoms, including anaphylaxis; swelling of the lips, eyes or face and skin rashes or hives.

Further, of the children with confirmed (or probable) food allergies, about 39% had had severe reactions in the past, and 30% had more than one allergy. The results were published online in Pediatrics on Monday (the research was funded by the Food Allergy Initiative, a nonprofit advocacy group.

Results showed that 25% of the food-allergic children were allergic to peanuts, 21% to milk and 17% to shell fish. Severe reactions, the authors found, were most common among children with tree nut (more than 50%) and fin fish (more than 40%) allergies. The reactions were more likely among 14- to 17-year-olds compared with 0- to 2-year-olds, and more likely in children with multiple food allergies.

However, the odds of children having allergies were actually higher in black and Asian children — and far lower in families that made less than $50,000 a year. Even though they were more likely to have allergies, minority children were less likely to have their allergies diagnosed by doctors, the study found.

The authors wrote, “The lack of data on the severity of childhood food allergy has made it difficult to articulate best practices.” They concluded, “These findings provide critical epidemiologic information to guide strategies for the prevention of food-induced reactions and for the diagnosis and management of childhood food allergies.”