Obesity refers to the long-term energy intake exceeds consumption, resulting in excessive energy stored in the body in the form of fat, and the accumulation of fat to the extent of damage to health. In layman’s terms, it means eating too much and consuming too little, turning into fat deposits in the body and affecting health. Obese people are often overweight Generally speaking, obese children or adults weigh more than 20% of normal weight, or reach the average weight of more than two standard deviations. Weight is related to height, so the medical use of body mass index (BMI) to determine whether overweight. The formula is BMI = weight (kg) / height (m) squared. 20 years of age or older adults normal BMI is 20-24, ≥ 24 is overweight; children under 14 years of age normal BMI is 15.5-21.2, ≥ 21 is overweight; 15-19 years of age young men and women normal BMI is 18-22, ≥ 22 is overweight. However, overweight people are not necessarily obese, and people with centripetal obesity (abdominal obesity) are not necessarily overweight. Some people who exercise a lot of muscles, strong bones, weight may be overweight, but there is not much body fat, it does not belong to obesity. And some patients with centripetal obesity have a lot of abdominal fat, but their whole body weight is not necessarily overweight. Therefore, WHO proposes to use the abdominal circumference/height (WHtR) to determine whether there is centripetal obesity: adults ≥0.5, boys ≥0.48, girls ≥0.46, is centripetal obesity. The incidence of various complications is higher in patients with centripetal obesity, and the risk of complications such as atherosclerosis, stroke, hypertension, coronary heart disease, diabetes and hyperlipidemia is 2-3 times higher than that of those with generalized obesity, and the thicker the waistline, the higher the risk. Therefore, the key to weight loss is to reduce the thickness!