Simple obesity is the most common type of obesity, accounting for 95% of the obese population. Body weight exceeds the standard weight by more than 20%. Calculated by body mass index BMI (weight (kg)/height 2/(m2)). Normal children <20< span="">, children >21 for obese, adults >24 for overweight, >26 mildly obese, >28 moderately obese, >30 severely obese. Etiology 1, genetic factors: both parents are obese, children have 70-80% of obesity. 2.Lifestyle and eating habits: too much food and too little activity. 3, neuropsychological factors: experimentally confirmed, stimulate the hypothalamus ventral medial nucleus, cause animals to refuse to eat. Completely destroy this nucleus, causing overeating. 4, hormone regulation: insulin promotes fat synthesis and inhibits decomposition of the main hormones; glucagon, ACTH, MSH, TSH, GH, ADH and glucocorticoids, is to promote fat decomposition and inhibit the synthesis of hormones. Endocrine factors are more closely related to secondary obesity. Hyperinsulinemia: insulin has a significant role in promoting fat accumulation, in a certain sense can be used as a monitoring factor of obesity, the role of insulin in promoting the increase of body fat is through the following links: ① promote glucose into the cell, and then synthesize neutral fat; ② inhibit the fat in the adipocyte fat use. 5. Other: brown adipose tissue abnormalities Brown adipose tissue is an adipose tissue that has been discovered only in recent years and is involved in the regulation of energy balance. Lack of brown fat, energy consumption is reduced. Symptomatic obesity: including cortisolism, obesity reproductive incompetence, polycystic ovary syndrome, Laumont-Bee syndrome, Prader-Willi syndrome, hypothyroidism Examination Weight measurement Blood routine, blood glucose and lipid, cortisol, liver function biochemistry, nail function, sex hormones, etc. Complications Obesity is likely to be complicated by various common complications are: ① hypertension; ② coronary heart disease; ③ diabetes and (3) diabetes mellitus and hyperlipidemia; (4) dyspnea syndrome (Pickwick syndrome); (5) fatty liver and gallstones; (6) reproductive and sexual insufficiency; (7) arthropathy caused by excessive load on the lower limbs; (8) psychological disorders. Treatment 1) Dietary control, adjustment of dietary structure, appropriate increase in high-protein foods (fish, soybeans); 2) Exercise therapy; 3) Drug therapy: 1) appetite suppression, such as fenfluramine; 2) fat absorption inhibitors, orlistat; 3) drugs to increase energy expenditure, due to the side effects of many applications rarely.