Prevention of food allergies.

Any rational approach to the prevention of food allergies must be based on the diversity of mechanisms which are involved in their pathogenesis. In addition to the IgE-mediated disorders which appear to be responsible for the largest number of cases, other immunologic (e.g., immune complex) and non-immunologic (e.g., enzymatic deficiencies) mechanisms appear to be involved. A preventive program should begin with a recognition that a potential problem exists and the identification of the individual at risk. This is accomplished by a careful documentation of IgE or other allergic reactivity in the individual or in family members. The prevention of intrauterine or postnatal sensitization is achieved by reduction in antigen transfer to the infant by maternal avoidance of potentially allergic foods in the last trimester and during lactation and by a restrictive infant diet. During the first years of infancy the encouragement of breast-feeding provides the dual benefit of eliminating one of the most common sensitizing food antigens, i.e., cow's milk protein, and providing passive s-IgA. The use of appropriate pharmacologic agents, e.g., cromolyn, may be yet another valuable adjunct in the prevention of food allergy.