Body Mass Index

Today, 64.5 percent of adults in the U.S. are overweight or obese. How do you know if you are among them? Two simple measures, body mass index (BMI) and waist circumference, provide useful estimates of overweight, obesity, and body fat distribution.

BMI measures your weight in relation to your height, and is closely associated with measures of body fat. You can calculate your BMI using this formula:

For example, for someone who is 5 feet, 7 inches tall and weighs 220 pounds, the calculation would look like this:

A BMI of 18.5 to 24.9 is considered healthy. A person with a BMI of 25 to 29.9 is considered overweight, and a person with a BMI of 30 or more is considered obese.

You can also find your weight group on the chart below. The chart applies to all adults. The higher weights in the healthy range apply to people with more muscle and bone, such as men. Even within the healthy range, weight gain could increase your risk for health problems.

Find your weight on the bottom of the graph. Go straight up from that point until you come to the line that matches your height. Then look to jind your weight group. The higher your BMI is over 25, the greater chance you may have of developing health problems.

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Because BMI does not show the difference between fat and muscle, it does not always accurately predict when weight could lead to health problems. For example, someone with a lot of muscle (such as a body builder) may have a BMI in the unhealthy range, but still be healthy and have little risk of developing diabetes or having a heart attack.

BMI also may not accurately reflect body fatness in people who are very short (under 5 feet) and in older people, who tend to lose muscle mass as they age. But for most people, BMI is a reliable way to tell if your weight is putting your health at risk.

How does overweight or obesity affect my health?

Extra weight can put you at a higher risk for many health problems including type 2 diabetes, high blood pressure, and heart disease.

Extra weight can put you at higher risk for these health problems:

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