VOLUME ONE. History, Definitions, and Prevalence. Obesity Has Always Been with Us: An Historical Introduction. Measurement of Total Adiposity, Regional Fat Depots, and Ectopic Fat. Anthropometric Indicators in Relation to the Gold Standards. Worldwide Prevalence of Obesity in Adults. Prevalence and Consequences of Pediatric Obesity. Obesity in Older Adults in the United States. Gender, Ethnic, and Geographic Variation in Adiposity. Biological Determinants of Obesity. Genetic Component to Obesity: Evidence from Genetic Epidemiology. Genes and the Predisposition to Obesity. Epigenetic Mechanisms in Obesity. Fetal and Early Postnatal Life Determinants of Adiposity. Animal Models of Obesity: Perspectives on Evolution of Strategies for Their Development and Analysis of Their Phenotypes. Animal Models of Obesity: Nonhuman Primates. CNS Regulation of Energy Balance. Gastrointestinal Regulation of Energy Balance. Gut Microbiome and Obesity. Sympathetic Nervous System and Endocrine Determinants of Energy Balance. Insulin Resistance and Obesity. White and Brown Adipose Tissue Development. Adipose Tissue Metabolism, Adipokines, and Obesity. Visceral Adipose Tissue and Ectopic Fat Deposition. Skeletal Muscle Metabolism and Obesity. Mitochondrial Bioenergetic Aspects of Obesity and Weight Loss. Resting Metabolic Rate, Thermic Effect of Food, and Obesity. Energy Cost of Exercise, Postexercise Metabolic Rates, and Obesity. Energy Partitioning, Substrate Oxidation Rates, and Obesity. Viral Infections and Adiposity. Behavioral Determinants of Obesity. Obesity: Influence of the Food Environment on Ingestive Behaviors. Obesity and Related Eating Disorders. Tobacco Use, Smoking Cessation, and Obesity. Breastfeeding and Later Obesity. Beverages and Obesity: Biology, History, Trends. Sedentary Time and Obesity. Occupational Work and Obesity. Leisure-Time Physical Activity and Obesity. Sustained Short Sleep and Risk of Obesity: Evidence in Children and Ad