The aim of this study was to investigate the degree to which parents alter the diets of their children on the basis of perceived reactions. From a population-based sample of 2979 2-year old children with reactions to egg or milk perceived by their parents, one third had strict limitations on the intakes of these foods, representing 2.5% of the children in the cohort. In approximately 1 of 6 families the strict diets were initiated without consulting a doctor, and in a substantial proportion the restrictions were unwarranted. High maternal education level and irritability attributed to food were among the risk factors for unwarranted diets. On the other hand, many children, in whom an adverse reaction was verified, lacked appropriate diet restrictions. We conclude that the handling of adverse reactions to food frequently occurs outside the medical care system at the cost of correct diagnosis and appropriate diets.