Alternative Names body mass index, BMI, Quetelet's index
Definition Body mass index (BMI) is a standard used to judge body fatness. It is determined by dividing an individual's weight (in kilograms) by an individual's height (in metres) squared.
Information BMI tables are replacing the standard height-weight tables. BMI, in combination with waist measurement, can be used to determine if an individual is at increased risk for developing a number of chronic diseases. Unlike height-weight tables, BMI takes into account body composition. Body composition is the ratio of lean tissue to fat tissue that makes up an individual's overall weight.
A BMI between 20 and 25 is desirable for most adults. Individuals with a BMI between 25 and 30 are considered overweight. In addition, those more than 30 may be at increased risk for other diseases if they have 2 or more risk factors, such as high blood pressure, high cholesterol, type 2 diabetes, or sleep apnoea. A BMI of more than 30 indicates obesity. A BMI of more than 40 may increase risk of early death. It is considered morbidly obese.
Author: Reviewer: eknowhow Medical Review Panel Editor: Dr John Hearne Last Updated: 30/11/2004 Contributors Potential conflict of interest information for reviewers available on request
