Body Mass Index (BMI)

Body mass index, or BMI, is a new term to most people. However, it is the measurement of choice for many physicians and researchers studying obesity. BMI uses a mathematical formula that takes into account both a person's height and weight. BMI equals a person's weight in kilograms divided by height in meters squared. (BMI=kg/m2).

Risk of Associated Disease According to BMI and Waist Size

BMI   Waist less than or equal to
40 in. (men) or
35 in. (women)
Waist greater than
40 in. (men) or
35 in. (women)
18.5 or less Underweight -- N/A
18.5 - 24.9 Normal -- N/A
25.0 - 29.9 Overweight Increased High
30.0 - 34.9 Obese High Very High
35.0 - 39.9 Obese Very High Very High
40 or greater Extremely Obese Extremely High Extremely High