Body mass index (or BMI) is defined as the person’s body weight divided by the square of his or her height. Body mass index may be calculated using the formula below (BMI Calculator)

BMI is a crude method to estimate obesity

Body Mass Index (BMI) is one of the ways to determine when extra fat accumulation translates into health risks. Body mass index is a measure which takes into account a person’s weight and height to gauge total body fat in adults. The higher the body mass index, the greater the risk of developing additional health problems. The following chart describes the various categories of obesity based on body mass index:

BMI = 19 - 24 Desirable
BMI = 25 - 30 Overweight
BMI = 31 - 35 Obese, category 1
BMI = 36 - 40 Obese, category 2
BMI > 40 Severe obesity

Heart disease, diabetes and high blood pressure are all linked to being overweight and obese.