Prevalence of severe obesity in adults in the United States

Abstract

This report presents estimates of the prevalence of severe obesity in the civilian noninstitutionalized population 20 to 74 years of age in the United States by sex and age, based on body measurements obtained from the Health and Nutrition Examination Survey 1971-1974 conducted by the National Center for Health Statistics. The Health and Nutrition Examination Survey (HANES) was designed to measure the nutritional status of the U.S. population as well as certain aspects of the general health status and medical care needs. A nationwide probability sample of 28,043 persons was selected to be examined in 65 primary sampling units visited between April 1971 and June 1974. Findings in this report are based on examinations of 12,900 persons aged 20 to 74 years, from a total group of 20,749 examined persons aged 1 to 74 years. These fmdings are shown as national estimates based on weighted observations, i.e., the data obtained for each examined person are extrapolated to the level of the total population of which the sample was representative. The appropriate weights were used to account for both sampling fractions and survey response results. The HANES nutrition examination included a general medical examination by a physician for indicators of nutritional deficiencies, skin examination by a dermatologist, and dental examination by a dentist. Body measurements were taken by a trained technician; a dietary interview was administered consisting of a 24-hr recall of food consumption and a food-frequency questionnaire. Routine laboratory tests were performed on whole blood, serum, plasma, and urine. A description of the sampling process, HANES operation, has been published previously (1).