Avoidance diets--how selective should we be?

Selective avoidance diets are the most common means of treatment for food allergies and other types of food sensitivities. With IgE-mediated food allergies, adverse reactions can occur in some patients to very small amounts of the offending food; therefore, strict avoidance of the offending food must be accomplished. With other, non-immunological types of food sensitivities, such as lactose intolerance and sulfite sensitivity, the patients are able to tolerate some, although variable, amounts of the offending substance. Thus, the degree of tolerance is an important concern in the construction of safe and effective avoidance diets. Another issue in the development of selective avoidance diets is the presence of the allergen in specific foods. For example, the peanut allergen is a protein which is not present in peanut oil. Consequently, peanut oil is safe to consume for peanut-allergic patients. Cross-reactivity is yet another concern in the development of selective avoidance diets. Cross reactions can occur between related species of legumes, crustacea, eggs, and milk for example. The construction of a safe and effective avoidance diet for food allergies and sensitivities requires consideration of several important issues and is a responsibility that should not be taken lightly.