What's Behind the Rise in Food Allergies?

Maybe it's crappy methodology... at least if you believe Dr. Marc Riedl's new study in the Journal of American Medicine Association.

Here's a nice bit from the NYT's writeup:

For their report, Dr. Riedl and his colleagues reviewed all the papers they could find on food allergies published between January 1988 and September 2009 — more than 12,000 articles. In the end, only 72 met their criteria, which included having sufficient data for analysis and using more rigorous tests for allergic responses.

“Everyone has a different definition” of a food allergy, said Dr. Jennifer J. Schneider Chafen of the Department of Veterans Affairs’ Palo Alto Health Care System in California and Stanford’s Center for Center for Primary Care and Outcomes Research, who was the lead author of the new report. People who receive a diagnosis after one of the two tests most often used — pricking the skin and injecting a tiny amount of the suspect food and looking in blood for IgE antibodies, the type associated with allergies — have less than a 50 percent chance of actually having a food allergy, the investigators found.

Lovely.

Oh, and accepted dogma? You're next:

Authors of the new report — and experts on the guidelines panel — say even accepted dogma, like the idea that breast-fed babies have fewer allergies or that babies should not eat certain foods like eggs for the first year of life, have little evidence behind them.