Body Mass Index

Body Mass Index or BMI is a tool for indicating weight status in adults. It is a measure of weight for height. For adults over 20 years old, Body Mass Index (BMI) falls into one of these categories:

Body Mass Index correlates with body fat. The relation between fatness and Body Mass Index differs with age and gender. For example, women are more likely to have a higher percent of body fat than men for the same Body Mass Index. On average, older people may have more body fat than younger adults with the same Body Mass Index.

For more information about overweight among adults, see Clinical Guidelines on the Identification, Evaluation, and Treatment of Overweight and Obesity in Adults. Bethesda, MD: NHLBI, 1998.

How does Body Mass Index relate to health?

The Body Mass Index ranges are based on the effect body weight has on disease and death. As Body Mass Index increases, the risk for some disease increases. Some common conditions related to overweight and obesity include

• Premature death
• Cardiovascular disease
• High blood pressure
• Osteoarthritis
• Some cancers
• Diabetes

Body Mass Index is only one of many factors used to predict risk for disease. Body Mass Index cannot be used to tell a person if he/she has a disease such as diabetes or cancer. It is important to remember that weight is only one factor that is related to disease.