The relationship between cow's milk exposure and type 1 diabetes.

Environmental factors are important for the development of Type 1 diabetes mellitus. They likely account for changes in the incidence of this disease over time, as well as the well-documented differences in incidence in ethnically and genetically similar people living in different parts of the world. There is a relationship between early cow's milk exposure and the development of Type 1 diabetes in humans, and between early cow's milk exposure and the development of autoimmune diabetes in rodent models of Type 1 diabetes. Moreover, some immunological studies have suggested a possible mechanism whereby exposure to cow's milk protein could result in beta-cell directed autoimmunity and subsequent Type 1 diabetes. Although provocative, the existence of alternative explanations for these epidemiological and biological observations, suggest that the data are insufficient to conclude that the observed associations represent causal relationships or to mandate changes in recommendations for infant feeding. The question of whether or not avoidance of cow's milk protein in infancy will prevent Type 1 diabetes can, however, be tested in an international randomized clinical trial of infant diets, which is currently under review.