The National Institutes of Health and the American Heart Association joint research group jointly showed that: the limbs are thin but the face and waist more bloated “central obesity” people, even if the BMI (referred to as body mass index, is the weight of kilograms divided by the height of the square of the number derived from the number to measure the degree of fat and thin a standard) the same The mortality rate is also higher than that of other obese people. The central obesity, is specially refers to except the limbs in the body in the central part of the waist and abdomen, especially the viscera fat accumulation and caused by the obesity. It is more common among hypertensive and diabetic patients, and lifestyle problems are a major cause, mostly accompanied by symptoms of adrenal hormone secretion disorder. The study was conducted with 15,200 men and women aged 18-90 years who participated in the Third American Nutrition and Health Survey (NHANES III) between 1988 and 1994. The research team conducted a follow-up survey between 2010 and 2012 to analyze the relationship between obesity type, BMI and mortality. The results of the study were: “central obesity” people with normal BMI (U.S. benchmark 22-24) had 1.87 times higher mortality in men and 1.48 times higher mortality in women compared to other people with normal BMI. Moreover, the mortality rate of “centrally obese” people with a normal BMI was twice as high as that of people diagnosed with overweight and obesity by BMI. Researchers have shown that “measuring obesity by BMI alone makes it difficult to accurately grasp health risks,” and reminded people to pay attention to their waist circumference and body shape changes. BMI is a relatively broad measure, so there will be although the BMI index is the same, but a uniform body body, while the other has a general belly. In the same situation, the “central obesity” people with thin limbs and big bellies have a higher mortality rate, so in the weight loss surgery standards also have a male waist circumference of more than 90cm; female waist circumference of more than 85cm consider surgery as appropriate.