''Fat around your waist is more biologically active and can do more damage to your body than weight around your hips,' says Roizen, co-author of You: On a Diet. People with apple shapes are at higher risk for health problems associated with being overweight. Some people gain weight in their abdominal regions (the so-called ''apple'' body shape.) Others are ''pear-shaped,'' with excess weight around the hips and buttocks. That's one reason some experts think waist circumference can be a better overall health measurement than BMI.Īnother is that your health is not only affected by excess body fat, but also by where the fat is located. Take for example, basketball player Michael Jordan: ''When he was in his prime, his BMI was 27-29, classifying him as overweight, yet his waist size was less than 30,'' says Michael Roizen, MD. In others, such as elderly people, BMI may appear normal even though muscle has been lost with aging. As a result, some people, such as heavily muscled athletes, may have a high BMI even though they don't have a high percentage of body fat. Nor does it distinguish between lean body mass and fat mass. These assessments would include measurements of body fat percentage, diet history, exercise patterns, and family history.įurther, BMI does not take into account age, gender, or muscle mass. Health professionals need to do further assessments to fully evaluate health risks. ''I think BMI is a very good and easy screening tool,'' says obesity expert, Cathy Nonas, MS, RD, a spokeswoman for the American Dietetic Association.īut while it is a simple, inexpensive method of screening for weight categories, it is not a diagnostic tool. The Measurement of ChoiceīMI is the measurement of choice for most health professionals. (This BMI calculator is for use in the evaluation of adults, not for children.)Īccording to the NIH definitions, a healthy weight is a BMI of 18.5-24.9 overweight is 25-29.9 and obese is 30 or higher. An easier way is to use WebMD's BMI calculator. For someone who is 5 feet 5 inches tall (65 inches) and weighs 150 pounds, the calculation would look like this: x 703 = 24.96. To calculate your BMI, divide your weight in pounds by your height in inches squared, then multiply the results by a conversion factor of 703. They replaced the old life insurance tables as a method to gauge healthy weight. In June 1998, in an effort to make sure doctors, researchers, dietitians, and government agencies were all on the same page, the National Institutes of Health announced its BMI guidelines. Or is there a place for both methods? What Is BMI? Some believe a better way might be to take out the tape measure and check your waist circumference.

Many health care experts think BMI is a useful tool to measure weight and health risks, but others question its accuracy. On the other hand, being too thin and having a BMI that's below the healthy range (18.5 to 24.9) can also be a health concern. According to a report in the August 2006 New England Journal of Medicine, excess body weight during midlife is associated with an increased risk of death. You should be aware of your BMI because of the health risks of being overweight (that is, having a BMI of 25 or over). What's your number - under 25 or over 35? Body mass index (BMI) may not be a term that's on everyone's lips, but it's important for your health to understand what it is and to know your number.Įssentially, BMI is a simple mathematical formula, based on height and weight, that is used to measure fatness.

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