The prevalence of obesity in children and adolescents is higher than 20 years ago in all racial-ethnic, age, and gender groups. In some population subgroups, more than 30% of children are overweight or at risk for being overweight.1 Unless intervention is successful, these children will contribute to the 35% of adult Americans who are obese, an increase of 30% in the past decade.2 The related health-care costs of adult obesity are estimated to be 45.8 billion dollars.1,3 The related disease risks include diabetes mellitus, hypertension, heart disease, stroke, gout, arthritis, and cancer.le The primary causes, experts agree, are poor nutrition and low activity levels, especially in individuals with a family history of obesity. Childhood obesity is the most critical challenge facing medical professionals today. .
Obesity results when susceptible (i.e., genetically pre-disposed) individuals are placed in "adverse" environments.1 Dietz4 has suggested that there are 3 critical periods for the development of obesity. These include: 1) the intrauterine environment or early infancy, 2) 5 to 7 years of age (adiposity rebound), and 3) adolescence. Both Law and associates and Dietz4 propose that weight and adiposity are entrained during early life. Furthermore, Troiano and associates6 state that often the obesity observed in adulthood originates during the early childhood years. There are several environmental factors that contribute to adult obesity. Low physical activity (PA); high-calorie, high-fat foods; and a resultant lowered exercise tolerance are some of many factors involved in the development of the disease.7" However, in young children under 6 years of age, the most important of these factors is parental obesity.1 It is well accepted that the environment of the family plays a k! ey role in the development of obesity in young children at risk for adult obesity and related diseases such as diabetes mellitus.