Why BMI?

Why measure your BMI? According to the National Institutes of Health (NIH), BMI "...is a reliable indicator of total body fat, which is related to the risk of disease and death."

Body Mass Index, or BMI, measures your weight and height, and is a better way to measure your weight than a scale. A high BMI is an indicator of increased risks of obesity related disease.

The down side of BMI is that it doesn't indicate where your fat is distributed.

Some people actually should not assess themselves with BMI: athletes and others who have a muscular build and the elderly as loss muscle mass may cause the calculations to underestimate body fat.

The NIH sets the following standards: a BMI of 25 to 29 means you're overweight; a BMI of 30 or more indicates obesity.

To assess your BMI, multiply your height in inches by itself. Now divide your weight by this number. Lastly, multiply this number by 703. The NIH also provides an easy online BMI calculator.

But remember, BMI does not distinguish between fat and muscle. So there is some gray area if you are just within a few digits of your ideal BMI.

You may also want to track your waist circumference in addition to your BMI as it is also a reliable indicator of disease risk.

Those who have a waist size of more than 40 inches for men, or 35 inches for women, have a higher risk for obesity-related health problems such as diabetes, high blood pressure, and heart disease.

Source:
National Institutes of Health. Aim for a Healthy Weight: Assess Your Risk. 17 April 2007.