food allergy symptoms


A true food allergy or food hypersensitivity is an adverse reaction to a food that involves the immune system.

The common foods implicated are egg, milk, peanut, sesame and wheat, soy, fish, and tree nuts which account for about 95% of reactions.  Symptoms of food allergies typically present within 1 hour of ingestion and may include itchy rash, hives, wheezing, shortness of breath, swelling of the lips, tongue and throat, and gastrointestinal reactions including nausea, abdominal cramps, vomiting and diarrhea.  In severe cases, anaphylaxis can occur.

There are many other types of symptoms of food reactions, distinct from the allergic reaction described above.  Using milk as an example, an immunologic response would occur as a result of allergy antibodies interacting with the protein in cow’s milk, whereas the non-immunologic response would be lactose intolerance, wherein there is insufficient lactase to break down the sugar (lactose) in milk.

Other examples of non-allergic food reactions include food poisoning, food intolerance (e.g. spicy foods), chemical effects of food (e.g. caffeine), and gluten sensitivity.