What Is a Food Allergy?

Food allergies are physical symptoms triggered by an immune reaction directed toward the foods we eat.  Food allergies can affect multiple organs and cause a range of symptoms, some of which may become life-threatening.  Food reactions typically are not due to food allergies, however, but rather, food intolerances.  Unlike food allergies, the symptoms of food intolerances are generally restricted to the gastrointestinal tract. Food intolerances may be caused by sensitivity to an ingredient in the offending food (e.g., lactose found in dairy products) or by a pre-existing gastrointestinal condition, such as inflammatory bowel disease.

How Are Food Allergies Tested?

Food allergy testing requires that a blood sample is collected and submitted to a clinical laboratory that performs the test. A food allergies or food sensitivity is usually associated with an elevated level of serum IgE antibodies against the food allergen. Food allergy testing measures the quantity of the food allergen present in the patient’s blood. In some cases, IgG and IgA antibodies associated with food sensitivities may be measured.