A food allergy is an immunologic response to a food protein. It is estimated that up to 12 million Americans have food allergies of one type or another, and the prevalence is apparently rising. Six to eight percent of children under the age of three have food allergies and nearly four percent of adults have them. The most common food allergies in adults are shellfish, peanuts, tree nuts, fish, and eggs, and the most common food allergies present in children are milk, eggs, peanuts, and tree nuts.At this time, there is no cure for food allergies. Treatment consists of avoidance diets, in which the allergic person avoids all forms of the food to which they are allergic. For people who are extremely sensitive, this may involve the total avoidance of any exposure with the allergen, including touching or inhaling the problematic food as well as touching any surfaces that may have come into contact with it. Food allergy is distinct from food intolerance, which is not caused by an immune reaction.Persons diagnosed with a food allergy may carry an autoinjector of epinephrine such as an EpiPen or Twinject, wear some form of medical alert jewelry, or develop an emergency action plan, in accordance with their doctor.