Introduction
A food allergy is an abnormal response of the body to a certain food. It is important to know that this is different than a food intolerance, which does not affect the immune system, although some of the same signs may be present.
Before having a food allergy reaction, a sensitive person must be exposed to the food at least once before. It is the second time the person eats the food that the allergic symptoms happen. At that time, when IgE (immunoglobin E) antibodies react with the food, histamines are released, which can cause hives, asthma, itching in the mouth, trouble breathing, stomach pains, vomiting, or diarrhea.
Food allergy causes an immune system response, causing symptoms that range from uncomfortable to life-threatening. Food intolerance does not effect the immune system, although some symptoms may be the same as in food allergy.
Approximately 90 percent of all food allergies are caused by eight foods:
- milk
- eggs
- wheat
- soy
- tree nuts
- fish
- shellfish
- peanuts
Eggs, milk, and peanuts are the most common causes of food allergies in children, with wheat, soy, and tree nuts also included. Peanuts, nuts, fish and shellfish commonly cause the most severe reactions. Nearly 3 percent of children have food allergies. Although most children "outgrow" their allergies, allergy to peanuts and tree nuts may be life-long.