Food Allergy

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Food allergy facts

  • Food allergy is not common but can be serious.
  • Food allergy differs from food intolerance, which is far more common.
  • The more frequent types of food allergies in adults differ from those in children.
  • Children can outgrow their food allergies, but adults usually do not.
  • The diagnosis of food allergy is made with a detailed history, the patient's diet diary, or an elimination diet.
  • Food allergy is treated primarily by dietary avoidance.

What is a food allergy?

Either food allergy or food intolerance affects nearly everyone at some point. When people have an unpleasant reaction to something they ate, they often think that they have an allergy to the food. Actually, however, only about 3% of adults and 6%-8% of children have clinically proven true allergic reactions to food.

This difference between the prevalence of clinically proven food allergy and the public's perception of the problem is due primarily to misinterpreting food intolerance or other adverse reactions to food as food allergy. A true food allergy is an abnormal response to food that is triggered by a specific reaction in the immune system and expressed by certain, often characteristic, symptoms. Other kinds of reactions to foods that are not food allergies include food intolerances (such as lactose or milk intolerance), food poisoning, and toxic reactions. Food intolerance also is an abnormal response to food, and its symptoms can resemble those of food allergy. Food intolerance, however, is far more prevalent, occurs in a variety of diseases, and is triggered by several different mechanisms that are distinct from the immunological reaction responsible for food allergy.

People who have food allergies must identify and prevent them because, although usually mild and not severe, these reactions can cause devastating illness and, in rare instances, can be fatal.

Medically Reviewed by a Doctor on 3/25/2015

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Food Allergy - Describe Your Experience Question: Please describe your experience with a food allergy.
Food Allergy - Symptoms and Signs Question: What are the symptoms and signs of your food allergy?
Food Allergy - Allergy Shots Question: Please discuss your experience with allergy shots in preventing or decreasing food allergies.
Food Allergy - Common Foods Question: What foods are you allergic to? Please share what happens when you eat the food and how you avoid it.
Food Allergy - Testing and Diagnosis Question: What types of tests and exams led to a food allergy diagnosis?
Food Allergy - Treatment Question: Do you receive medical treatment for your food allergy, or do you avoid the food? Please discuss your experience.
Learn how food allergies differ from food intolerance.

Symptoms and Signs of Food Allergies Vs. Food Intolerance

With a food allergy, symptoms may occur almost immediately or up to hours after consuming the particular food. These symptoms may affect the respiratory system, gastrointestinal tract, cardiovascular system, or the skin.

Food allergy symptoms can include:

  • skin rash or hives,
  • swelling of the tongue and throat,
  • breathing problems including asthma,
  • vomiting or diarrhea, and
  • abdominal pain and cramping.