The BMI, or Body Mass Index, is a measure of relative weight in adult humans to assess health and nutritional status. The BMI is an attempt to quantify the amount of tissue mass that includes muscles, fat, and bones in an individual and then categorize that person as underweight, average weight, overweight, or obese. That allows a person to decide whether they need bariatric surgery or not.
BMI is used to estimate an individual's body fat. Although it is easy to use, BMI may not be the best or most accurate way to measure how much excess weight you carry or if you are at risk for health problems related to being overweight or obese. For example, two people may have the same BMI and total body fat, but their muscle and bone mass percentage could vary greatly.
People who have a high body fat percentage, regardless of their BMI, may be at risk for various health problems even if they do not look overweight. Many people with a BMI considered within the normal range have a high percentage of body fat.
Body Mass Index (BMI) is a measure of body fat based on height and weight that applies to both adult men and women.