Why Are Food Allergies on the Rise in Children?

(Nov. 16) -- The number of children with allergies to certain foods is rising at an alarming rate.

That's the conclusion of a new report from the National Center for Health Statistics that will be published in the December issue of the journal Pediatrics. Between 1997 and 2007, the NCHS analysis found, child food allergies -- such as those to peanuts, eggs, milk and wheat -- jumped by 18 percent.

"We honestly don't know why there has been this increase," said Amy Branum, health statistician at the National Center for Health Statistics and the study's lead author.

Analyzing doctors' records as well as surveys taken by parents, Branum determined that 4 percent of all U.S. children now have food-related allergies. Furthermore, the number of doctor and hospital visits made by children seeking treatment for food allergy issues has tripled since 1992.




Interestingly, when the NCHS expanded its scope to include nonfood allergies, it found that respiratory ailments such as asthma have not increased all that much over the same period, and cases of hay fever actually went down. Eczema, however, had risen 13 percent. Eczema is often triggered by food allergies.

Carl and Sophie Chuang of Albany, Calif., have never had any allergies to foods, but when their 12-year-old daughter showed signs of eczema when she was just months old, a doctor diagnosed an allergy to breast milk. Two years later, more outbreaks of eczema led to positive allergy tests to raw eggs, cheese and nuts.

"She developed rashes and was always scratching," said Carl Chuang. "She can tolerate small amounts of some of these foods, but still, when she puts something in her mouth that she's allergic to, she can tell and sometimes will throw up."

Branum said there is no definitive explanation as to what might be causing the rise in reported child food allergies.

"Certainly parents have become more aware of the issue of food allergies, as have doctors, so some of this increase can probably be explained because of heightened awareness," she said.

"On the other hand, we found the biggest rise in food allergy reporting is in the Hispanic population, who are often missing out on health care when compared to other groups."

A forthcoming federally funded study by the National Institutes of Heath will attempt to identify causal reasons for the increase in food allergies in children by looking at several factors, including breast-feeding, diet and exposure to pets, Branum said.

"I don't want to scare anybody, but I do think we're seeing increases in something we should start taking seriously."