Oral tolerance and allergy.

Food allergy prevalence is increasing in the developed world. It's estimated that each year in the US, anaphylaxis to food results in 30,000 emergency room visits and 150 deaths. Over the past few decades, there has been a tremendous effort to better understand the pathogenesis of food allergy and mechanisms of food tolerance. In this article we review the structural of the gastrointestinal immune system and mechanisms of natural tolerance to food. We then review the factors that may result in the IgE mediated hypersensitivity reaction to food allergens resulting in clinical food allergy. Lastly, we provide a brief review of the efforts to induce immune tolerance to patients with food allergy.