Over the past few decades, the prevalence of food allergy has risen. If you were a student in the 1970s, you might have been the only food allergic student in your class – or even your school. This no longer seems to be the case.

The CDC reports that from 1997 to 2007, the prevalence of food allergy increased 18 percent. By 2007, about 4 percent of people had been diagnosed with food allergy. A current estimate by another research group in 2011 puts the rate for children even higher, at about 8 percent. Researchers now estimate that between 3 million and 6 million children in the United States have food allergies.

Allergies, asthma and eczema

This increase in food allergy also coincides with a rise in asthma, allergic rhinitis and eczema. This is because the risk of having any one of these conditions increases if you have one or more of the others.

For example, 29 percent of children with food allergy also report having asthma, compared with only 12 percent of children without food allergy. The numbers for allergic rhinitis and eczema are similar: 30 percent vs. 9 percent for allergic rhinitis, and 27 percent vs. 8 percent for eczema.

Reasons for rise still sketchy

Theories as to why food allergies are on the rise are numerous but lack convincing scientific proof. Some scientists believe the diet of people in developed countries has changed our intestinal bacteria, leading to more allergies.

Others assume that because our population experiences fewer infections in general, the immune system has less work to do and refocuses on allergens. This has been coined the hygiene hypothesis.

Still others speculate it may be the way we prepare our foods (for example, roasting peanuts vs. boiling them) or the age we introduce them. (We’re now asking: Is it better to first feed commonly allergenic foods at 3 months or at 3 years of age?)

Research is ongoing, and so far there are no scientifically proven ways to avoid the development of food allergies.

A silver lining to the increased prevalence of food allergy is that schools, daycares and restaurants are now more aware of their existence and many already have policies in place for dealing with the food allergic people they encounter. This makes food allergic families feel more comfortable when their kids cannot be under their direct supervision.

New food allergy therapies

Because of the dramatic increase in food allergies, there’s also been increased research. While avoidance and treatment of reactions remain our mainstays, new methods for treating food allergies are coming. Desensitizing children by giving them very small portions of the food they are allergic to may be available in the next one to two years. Talk to your allergist to keep up on the latest treatments.

Check back often, and look for Dr. Sarah Kehl’s upcoming post on emerging therapies in food allergies.