Video - Food allergy

A food allergy is an immune system response to a food that the body mistakenly believes is harmful. When someone has a food allergy, the body's immune system produces antibodies called IgE (immunoglobulin E) in response to proteins in the food. These antibodies attach themselves to cells that line the respiratory tract, digestive tract, and skin.

When the person eats or inhales the food containing those proteins, the IgE antibodies trigger the release of histamine and other chemicals. These chemicals cause allergic symptoms such as wheezing, chest tightness, nausea, vomiting, cramps, diarrhea, itchy skin or throat, swelling of lips, tongue, and eyes, or anaphylaxis. Food allergies can be life-threatening, so it's essential to be aware of them and take steps to avoid exposure to the offending food.