The standard weight of middle-aged people can be roughly calculated according to the formula for ideal weight, which is height (in cm) minus 105, with a fluctuation of 10% up and down as normal, more than 10% to 20% as overweight, and more than 20% as obese. For normal adults, the evaluation of standard weight has no necessary relationship with age, and weight is not the only indicator to reflect the body fat content, different people according to body type and gender and other evaluation criteria are different. In addition to the formula for calculating ideal body weight, body mass index, waist circumference, and waist-to-hip ratio are commonly used in medicine for a comprehensive assessment of the human body. 1. Body Mass Index (BMI), commonly used to express BMI, the formula is, BMI (kg/m2) = weight (kg) / [height (m)]2, the standard BMI for 18.5 ~ 23.9. 2. Waist circumference is a simple and commonly used indicator to measure the degree of abdominal fat accumulation and body fat distribution, and can be used to assess visceral fat content. Generally speaking, the waist circumference for men is 85cm, while that for women is about 80cm. 3. Waist-hip ratio, i.e. the ratio of waist circumference to hip circumference, is standardized at 0.9 for men and 0.85 for women. Note: Waist and hip circumference measurements must be in accordance with the standard in order to be accurately assessed; abnormal weight or significant fluctuations within a short period of time should be taken seriously, and timely consultation should be sought if necessary.