An allergy is an adverse immune response to a foreign substance that doesn’t cause a reaction in most people. The immune system produces a special antibody, called immunoglobulin E (IgE) when it encounters this foreign substance. Immunologists still debate about the exact cause of allergies, although many theorize that allergies are caused by an imbalance between an inflammatory immune reaction and the anti-inflammatory, IgE-producing immune reaction.1
Children usually experience the allergy symptoms the very first time that they eat a food. Food-related allergies are the leading cause of emergency room visits in which the young child cannot breathe. The prevalence of allergies keeps increasing. From 1997 to 2008, the prevalence of children with peanut allergies jumped from 0.2% to 1.1%.2 In 2017, 2.2% of children had a peanut allergy.3