Simple calculation of weight is: standard weight (kg) for men = height (cm) – 105; standard weight (kg) for women = height (cm) – 100. 10%-20% below the normal range means too thin; >20% below the normal range is wasting; 10%-20% above the normal range is overweight; >20% above the normal range is obese. Therefore, the standard weight of a male with a height of 183 is 78kg, and the standard weight of a female is 83kg. according to the above standard weight, within the range of ±10% below is normal weight; below 10%-20% of this weight (i.e. 62.4-70.2kg for male, 66.4-74.7kg for female) is thin weight; below 20% of this weight (i.e. 62.4kg for male, 66.4kg for female) is thin weight. If the weight is less than 20% (i.e. 62.4kg for men and 66.4kg for women), it is considered thin; if the weight is higher than 10%-20% (i.e. 85.8-93.6kg for men and 91.3-99.6kg for women), it is considered overweight; if the weight is higher than 20% (i.e. 93.6kg for men and 99.6kg or more for women), it is considered obese. If there is a significant change in weight, it is recommended to go to the hospital for examination to rule out disease causes. Those who are below normal weight need to increase their diet appropriately, avoid picky eating and partial eating, and pay attention to moderate exercise to enhance immunity; those who are overweight can enhance physical exercise, moderate and gradually reduce the amount of diet, and avoid high oil, high sugar and high calorie food.