People with BMIs between 19 and 22 live longest. Death rates are higher for people with indexes above 25. A BMI of 25 to 29.9 is considered overweight and over 30 is considered obese.The BMI is not infallible. It is possible for a healthy, muscular athlete with low body fat to be classified obese so trained athletes should base thier weight on the percent body fat. (Source BBC)
BMI or Body Mass index