The prevalence of overweight and obesity has reached epidemic proportions in the United States. Nearly two-thirds of adult Americans are overweight or obese, and the prevalence of overweight among American children between the ages of 6 and 19 has tripled during the past 20 years, from 5 percent in 1980 to 15 percent in 2000. United States Surgeon General Richard Carmona calls obesity America's single biggest health problem. The evidence for the relationship between obesity and several chronic illnesses is becoming increasingly clear. Although changing behavior is difficult, growing recognition of the health impact and costs associated with overweight and obesity, combined with increased knowledge regarding effective prevention and treatment interventions, provide momentum for addressing this epidemic. However, reversing current trends will require a multifaceted public health approach.
Myriad genetic, social, and environmental factors contribute to overweight and obesity. The rapid increase in their rates in the United States, however, suggest that social and environmental influences have played the major role in contributing to the nation’s overweight and obesity problem. In particular, recent social and environmental trends that have likely affected weight levels include: decreased physical activity in daily lives, increased use of commercial food products, larger commercial food portions, and increasing prevalence of community design that does not support physical activity. Furthermore, a relationship between obesity and low socioeconomic status has long been documented.