The exact cause of obesity is not clear, at present, consider the cause of obesity are genetic and environmental factors, material metabolism and endocrine function change, the number of fat cells increase, neuropsychiatric factors, life and diet habits and other related. Obesity according to the cause and pathogenesis can be divided into primary obesity and secondary obesity, as follows: 1, primary obesity, also known as simple obesity, is the most common of all kinds of obesity, mainly due to poor eating habits and stationary lifestyle, and is not secondary to other diseases, simple obesity and overeating obesity two, physical obesity that is two parents obesity and family genetic related. Overeating obesity is also called active obesity, is due to the person adult conscious or unconscious over-eating, the calorie intake greatly exceeds the body growth and activity needs, excess heat into fat, promote the fat cell hypertrophy and cell number increase, fat mass accumulation and lead to special obesity; 2, secondary obesity is due to hypothalamus pituitary and other diseases, cortisolism, insulinoma, etc. The obesity caused by organic disease.