what is a food allergen
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.he most common food allergens include peanuts, milk, eggs, tree nuts, fish, shellfish, soy, and wheat â these foods account for about 90% of all allergic reactions. The most common food allergies in adults are shellfish, peanuts, tree nuts, fish, and egg.