What is obesity?
Obesity is defined as an excessively high amount of body fat or adipose tissue in relation to lean body mass. The amount of body fat (or adiposity) includes concern for both the distribution of fat throughout the body and the size of the adipose tissue deposits. Body fat distribution can be estimated by skin fold measures, waist-to-hip circumference ratios, or techniques such as ultrasound, computed tomography, or magnetic resonance imaging.
Prevalence
Results from the 1999-2002 National Health and Nutrition Examination Survey (NHANES), using measured heights and weights, indicate that an estimated 65 percent of U.S. adults are either overweight or obese. This represents a prevalence that is 16 percent higher than the age-adjusted overweight estimates obtained from NHANES III (1988-94).
Increases in obesity have occurred across virtually in all ethnic, racial, and socioeconomic populations and all age groups. Certain minority populations, particularly minority women, have been found to be at the greatest risk for obesity and hence, its co-morbidities. In NHANES III, nearly 50% of all African-American and Mexican women surveyed were obese. Within the 45- to 55-year-old age group, the prevalence of obesity was between 60% and 70%. The Healthy People 2000 objective for obesity established in 1990 set the goal for the incidence of obesity at no more than 20% of the adult US population by the year 2000. Clearly this goal is not being met. (Rippe, JM, Obesity as a Chronic Disease: Modern Medical and Lifestyle Management, J. Am Diet Assoc. 1998;98(suppl 2):S9-S15)
An estimated 97 million adults in the United States are overweight or obese, a condition that substantially raises the risk of morbidity from approximately 32 conditions including, in part, hypertension, dyslipidemia, type 2 diabetes, coronary heart disease, stroke, gallbladder disease, osteoarthritis, sleep apnea, respiratory problems, and endometrial, breast and colon cancer. Higher...