Body mass index (BMI) is a value derived from the mass (weight) and height of a person. The BMI is defined as the body mass divided by the square of the body height, and is expressed in units of kg/m2, resulting from mass in kilograms and height in metres.
What is body mass index (BMI)?
Body mass index (BMI) is a medical screening tool that measures the ratio of your height to your weight to estimate the amount of body fat you have. Healthcare providers calculate BMI by using weight in kilograms (kg) divided by the square of height in meters (m2).
In most people, BMI correlates to body fat — the higher the number, the more body fat you may have — but it’s not accurate in some cases. BMI alone does not diagnose health. Healthcare providers use BMI and other tools and tests to assess someone’s health status and risks.
High body fat may lead to heart disease, stroke and Type 2 diabetes. Low body fat may be related to malnutrition. Just the right amount of body fat helps vitamins and minerals get into your body. It also provides a source of energy for your body, helps maintain body temperature and protects your organs.
You should not use the standard BMI chart to evaluate a child’s or teenager’s weight. Talk to your child’s healthcare provider about the optimum weight range for their age and height.