Body mass index (BMI) is a measure of body fat based on height and weight that applies to adult men and women. It is calculated by dividing the weight in kilograms by the square of the height in meters. For example, a person who weighs 70 kg and is 1.75 meters tall would have a BMI of 22.6.
BMI is a simple and widely used measure of body fat that has been shown to be associated with a number of health risks, including heart disease, stroke, type 2 diabetes, and some types of cancer. It is also used to track changes in body fat over time.