Body mass index

The Body mass index (BMI) of a person is his or her weight in kilogrammes divided by the square of the height in metres.

Someone (male or female) with a BMI exceeding 27 is likely to have a significant excess of illness compared with other people; see obesity. A very low BMI may also be unhealthy.

Body mass index is not a useful measure for athletes, as their muscle mass is much greater than tht of an average person.