The body mass index (BMI) is a value derived from the mass (weight) and height of an individual. The BMI is defined as the body mass divided by the square of the body height, and is universally expressed in units of kg/m2, resulting from mass in kilograms and height in metres.Body mass index (BMI) is the recommended method for diagnosing overweight and obesity. It evaluates the relationship between body weight and height. While BMI is not a direct measure of excess body fat, it expresses the weight-height relationship and provides a more accurate measure than body weight alone.
There are many studies that show a link between BMI and the risk of several diseases as well as premature death. As BMI increases, so does the risk for:
- Diabetes- Cardiovascular disease- Stroke- Hypertension- Gallbladder disease- Osteoarthritis- Sleep apnea- Some cancers
BMI is used for risk assessment for the general population. Generally speaking, as a person's BMI increases, so does his or her risk of certain diseases. However, BMI does not distinguish between body fat and lean body mass and does not take into account location of body fat. For this reason, it's not an accurate measure of health for certain populations, such as people with higher than average muscle mass or people whose body composition may be skewed for other reasons.
Note: BMI is not an appropriate measure for athletes, children, pregnant women, or the elderly.