The Body Mass Index

The Body Mass Index, or BMI, is a simple formula based on a person's height and weight. Although it doesn't take into account the difference between muscle and fat like more sophisticated measurements, BMI gives doctors a quick, easy way to estimate concerns over a patient's weight, without having to measure body fat itself. In metric terms, BMI is derived by dividing a patient's weight in kilos by his or her height in meters, squared. For example: A person standing 1.80 meters tall and weighing 130 kg. would have a BMI of 40, qualifying them as morbidly obese. To reach the normal range, that person would have to lose a whopping 50 kg. Just to reach the upper limit of the overweight range would entail losing some 33 kg. BMI 18.5 underweight 18.5-25 normal 25-30 overweight 30-35 obese 35-40 severely obese 40-45 morbidly obese 50+ superobese