Body Mass Index (BMI) is weight (Kg) divided by the square of height (m). Body Mass Index, also known as BMI, is a standard used internationally to measure the degree of fatness and thinness of the human body and whether it is healthy or not. To calculate the BMI, you need to measure your weight (Kg), then measure your height (m), then calculate the square of your height, and then divide your weight by the square of your height for the BMI. The BMI for Asian adults is recommended to be kept between 18.5~23.9, 24~27.9 is considered overweight, and 28 or more is considered obese. If the body mass index is too high, suggesting obesity, the patient needs to pay attention to diet, and the need for appropriate exercise, if the body mass index is too low, suggesting thin, the patient needs to supplement nutrition.