The federal government commissioned a report that found poorly done studies in food allergy research and tests with misleading results for food allergy diagnosis. The team reviewed over 12,000 articles on food allergies, but only 72 met their criteria for sufficient data and rigorous testing. Their report is part of a large project organized by the National Institute of Allergy and Infectious Diseases, aimed at bringing order to the chaos of food allergy testing. Hmm, no small feat.
Dr. Marc Riedl, an author of this report and an allergist and immunologist at UCLA, states that about half of the patients coming to his clinic with a food allergy diagnosis did not really have one. A survey showed that about 30 percent of the population believes they have food allergies, but Dr. Riedl states that only about 8 percent of children and less than 5 percent of adults do. He agrees that people can be allergic to foods with reactions ranging from a mild rash to life threatening responses, but his team believes that the true incidence is exaggerated …
Another member of the research team, Dr. Jennifer J. Schneider Chafen, of the VA Palo Alto Healthcare System and Stanford University School of Medicine, explained that food challenges, skin-prick testing and blood-serum testing for IgE antibodies to specific foods all have a role to play in diagnosing food allergies, but that no one test has sufficient ease of use or accuracy to be recommended over the other tests. In a story that sites Dr. Chafen, the “true incidence” of food allergy is said to be between 1 and 10 percent of the U.S. population.
Interesting; news stories on the same “confusion over food allergies” report even use drastically different numbers in clarifying what they believe to be the “true incidence” of food allergies. Also, if Dr. Riedl is in the ballpark, then their findings should not actually downplay food allergies. 8 percent of children and 5 percent of adults is far higher than anyone would have estimated in years past for true food allergies.
To note, Dr. Reidl says that he isn’t dismissing the idea that many people are responding to foods, but he says, “That accounts for a small percentage of what people term ‘food allergies.’ ” In other words, Dr. Reidl believes that many who are diagnosed with a food allergy may actually have a food intolerance.
Dr. Matthew J. Fenton, who oversees the guidelines project for the allergy institute, explained that while allergies involve the immune system, while intolerances generally do not. He cited an example of headaches from sulfites in wine, which is often labeled as an allergy, but should be more accurately described as an intolerance.
The team is expected to come up with evidence-based guidelines for diagnosing food allergies this summer. Hopefully they do not try to rush the results to meet a deadline, as it looks like they definitely have their work cut out for them.
- The Journal of the American Medical Association, May 2010
- “Doubt Is Cast on Many Reports of Food Allergies,” New York Times
- “Few High-Quality Studies on Food Allergies, Say Reviewers,” MSN Health