ABSTRACT
Introduction ............................................................................................................................................................................. 870 Etiology ................................................................................................................................................................................... 870 Genetic Causes ........................................................................................................................................................................ 870 Environmental Causes ............................................................................................................................................................. 871
Nutritional .......................................................................................................................................................................... 871 Inactivity............................................................................................................................................................................. 871 Psychosocial Factors .......................................................................................................................................................... 871 Physiologic States .............................................................................................................................................................. 872
Secondary Obesity .................................................................................................................................................................. 872 Energy Balance ....................................................................................................................................................................... 872
Appetite Regulation ........................................................................................................................................................... 873 Energy Partitioning ............................................................................................................................................................ 873 Energy Expenditure ............................................................................................................................................................ 874
Prevalence of Obesity ............................................................................................................................................................. 874 Assessment .............................................................................................................................................................................. 875
Body Mass Index ................................................................................................................................................................ 875 Fat Distribution .................................................................................................................................................................. 875 Insulin Resistance............................................................................................................................................................... 876
Medical Risks of Obesity (Comorbidities) ............................................................................................................................. 876 Treatment ................................................................................................................................................................................ 877
Goals .................................................................................................................................................................................. 877 Criteria for Choosing a Weight-Loss Program ................................................................................................................... 877 Diet ..................................................................................................................................................................................... 877 Low-Calorie Diets (LCDs) ................................................................................................................................................. 878
Implementation of Diet ................................................................................................................................................. 878 Low-Calorie, High-Fiber Diets .......................................................................................................................................... 878
Implementation of Diet ................................................................................................................................................. 879 Very-Low-Calorie Diets ..................................................................................................................................................... 880
Implementation of Diet ................................................................................................................................................. 881 High-Protein, Low-Carbohydrate Diets ............................................................................................................................. 882 Meal Replacement Diets .................................................................................................................................................... 882 Consequences of Dieting.................................................................................................................................................... 882 Exercise .............................................................................................................................................................................. 882 Behavior Modifi cation ....................................................................................................................................................... 882 Surgery ............................................................................................................................................................................... 882 Drugs .................................................................................................................................................................................. 882 Outcomes............................................................................................................................................................................ 884
References ............................................................................................................................................................................... 885 Additional Sources of Information on the Web ...................................................................................................................... 886
Obesity is a multifactorial disease that is growing in epidemic proportions. It is associated with signifi cant medical risks that may be ameliorated by modest weight loss. Exercise and behavioral modifi cation of diet are the cornerstones of treatment; pharmacotherapy and surgery may be useful adjuncts.
