The human immune system normally fights off bad bacteria or viruses that make people sick. A food allergy occurs when the immune system targets harmless food molecules as a harmful invading allergen and mobilizes to attack and get rid of the offending substance. True food allergies cause the body to produce abnormally large amounts of an antibody called immunoglobulin E — IgE for short. IgE antibodies fight the “enemy” food allergens by releasing histamine and other chemicals, which trigger the symptoms of an allergic reaction, including anaphylaxis, a potentially life-threatening reaction. Anaphylaxis can affect several areas of the body and threaten breathing and blood circulation. There is no cure for food allergies. Strict avoidance of food allergens — and early recognition and management of allergic reactions to food — are important measures to prevent serious health consequences.