A food allergy is an abnormal immune response to food. The signs and symptoms may range from mild to severe. They may include itchiness, swelling of the tongue, vomiting, diarrhea, hives, trouble breathing, or low blood pressure. This typically occurs within minutes to several hours of exposure. When the symptoms are severe, it is known as anaphylaxis. Food intolerance and food poisoning are separate conditions. Common foods involved include cow's milk, peanuts, eggs, shellfish, tree nuts, wheat, rice, and fruit.The common allergies in a region vary depending on the country.Risk factors include a family history of allergies, vitamin D deficiency, obesity, and high levels of cleanliness.Allergies occur when immunoglobulin E (IgE), part of the body's immune system, binds to food molecules.
