What is a food allergy?

A food allergy is caused when the body's immune system mistakes an ingredient in food—usually a protein—as harmful and creates a defense system (special compounds called antibodies) to fight it. An allergic reaction occurs when the antibodies are battling an "invading" food protein. Although a person could have an allergy to almost any food, the following 8 foods account for almost 90% of all food-related allergic reactions:

  • Milk
  • Eggs
  • Peanuts
  • Tree nuts (such as cashews and walnuts)
  • Fish
  • Shellfish
  • Soy
  • Wheat

What are the symptoms of a food allergy?

Symptoms of a food allergy can appear almost immediately or up to 2 hours after the food has been eaten. Symptoms include a tingling sensation of the mouth, swelling of the tongue and throat, hives, vomiting, abdominal cramps, difficulty breathing, diarrhea, a drop in blood pressure, and loss of consciousness. Severe allergy reactions called anaphylaxis, can result in death.

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