Physical and Behavioral Traits of Overweight and Obese Adults

Study Summary

This study will describe the phenotype (physical and behavioral traits) of overweight and obese people. It will characterize the hormones, metabolism, food preferences, fitness and physical activity levels, sleep patterns and thought processes in people with and without weight problems. Genetic material will be collected for studies of the internal codes that influence body weight. People over 18 years of age from all weight categories (lean, overweight, obese) who are reasonably healthy may be eligible for this study. Participants undergo the following tests and procedures: * Physical exam, electrocardiogram, blood and urine tests, instructions for recording food intake for 7 days * Metabolic studies for menstruating women. * Resting metabolic rate to study how many calories the body burns at rest. * Mixed meal test to measure hormones such as insulin that regulate blood sugar. * Glucose tolerance test to determine how sensitive the body is to insulin. * 24-hour energy expenditure to measure the amount of oxygen breathed in and the amount of carbon dioxide breathed out. * Repeat 24-hour energy expenditure. * Diurnal blood sampling and temperature assessment to study the body s internal clock. * Air-displacement plethysmography (Bod Pod) to measure body composition. * Dual energy x-ray absortiometry (DEXA) to measure body fat and bone density. * Repeat Bod Pod and DEXA. * Anthropometric measurements and bioelectrical impedance to measure height, weight, and circumferences, skinfold thickness, fluid status and percentage body fat. * Bromide dilution to measure the amount of water not in cells in the body. * Doubly labeled water to measure the amount of calories burned in a 7-day period. * 24-hour diet reports. * Endothelial reactivity to measure how the blood vessels stretch or dilate for assessing cardiovascular health. * Treadmill or bicycle exercise capacity test. * Physical activity monitor. * Unicorder to detect any breathing difficulties that may interfere wi

Primary Outcome

The aim of this study is to extensively phenotype subjects with varying degrees of obesity, as well as those with rare adipose disorders such as multiple symmetric lipomatosis (Madelung s disease), Dercums disease (adiposis dolorosa) and lipedema; to assess their hormonal, metabolic, cognitive and behavioral traits.

Conditions Studied

Study Locations (1)