What Is A Food Allergy?

A food allergy is the overreaction of the body's immune system to a
particular food or food additive. What causes an allergic reaction are food
allergens, or the proteins that are found in all plant and animal-based
foods. A single food may contain a number of different allergens. When a
food-allergic person eats an otherwise harmless food, antibodies in his
immune system cells release powerful substances that cause allergic
reactions.

Many people confuse food intolerance with food allergy. Food intolerance
is an abnormal physical response to a food or food additive. Unlike food
allergy, it is not caused by food proteins and does not involve the immune
system.

How Do I Know If I Have A Food Allergy?

Determining a food allergy is complicated by the fact that reactions to
food allergens produce a wide range of symptoms, and that these symptoms can
vary greatly not only among different people, but in any individual. While
most allergies are caused by a relatively small number of foods (cow's milk,
eggs, peanuts, wheat, soy, fish, and shellfish), their symptoms are often
similar to those involving food intolerance reactions.
Skin reactions such as hives and itchy scaly rashes (eczema);
gastrointestional reactions such as abdominal cramps, vomiting, and
diarrhea; and a severe life threatening whole-body reaction known as
anaphylaxis are only some of the more common allergic reactions to foods.
However, it is important to note that a number of these symptoms are also
symptoms of food intolerance.

How Does An Allergist Diagnose And Treat A Food Allergy?

As a first step in diagnosing a food allergy, an allergist will take a
detailed medical history, including specific information about diet and the
nature of the patient's symptoms. The doctor will also conduct a physical
examination. An allergist may use skin or blood tests to determine what
foods, if any, are causing an allergic reaction.
If a food allergy is diagnosed, the doctor will recommend a course of
treatment. Food allergies are treated by teaching the patient how to
eliminate certain foods from his diet, and by instructing the patient how to
best manage allergy symptoms if they do occur.