Primary prevention of chronic disease among children: the school-based "Know Your Body" intervention trials.

The "Know Your Body" project, initiated in 1975 with funding from the National Heart, Lung, and Blood and the National Cancer Institutes, was developed in response to the empirically-validated suggestion that the primary prevention of chronic disease should begin in childhood. The aim of the program is to favorably modify the population distributions of risk factors for these diseases through changes in their behavioral antecedents. The program is classroom-based and teacher-delivered, and consists of three primary intervention foci: diet, physical activity, and cigarette smoking prevention. The program was subjected to a field trial among two demographically dissimilar populations of schoolchildren in the New York City area. After five years of intervention in one of the populations, the program was associated with significant favorable changes in blood total cholesterol levels and dietary intake of total fat and carbohydrate. In both populations, the program was associated with significant favorable changes in knowledge. After six years of intervention, the program was associated with a significant net reduction in the rate of initiation of cigarette smoking. If these findings can be replicated among diverse populations of schoolchildren, they suggest that such programs may be effective in reducing the population risk for the future development of chronic disease.