Are you at a healthy weight? Learn how to calculate your BMI, a number that can tell you whether you fall within a healthy weight range.

More than one-third of all adult Americans (35.7 percent) are obese, according to statistics reported by the Centers for Disease Control and Prevention. To determine obesity, medical professionals refer to something called a person’s Body Mass Index, or BMI.

There are defined BMI ranges that can identify a person as underweight, healthy weight, overweight or obese.

As defined by medical professionals, an adult who has a BMI of 30 or higher is considered obese. An adult who has a BMI between 25 and 29.9 is considered to be overweight. Note that overweight and obese are two different classifications.

A healthy BMI falls between 18.5 and 24.9. And an underweight BMI falls below 18.5.

It’s easy to calculate your BMI, and many health-related websites and doctor’s offices have charts or calculators that can help you do so. You can also calculate your BMI by completing these simple calculations:

  1. Weigh yourself in pounds.
  2. Measure your height in inches.
  3. Use a pencil and paper or a calculator to square your height in inches (in other words, you multiple the number by that very same number).
  4. Now, divide your weight in pounds by the number you just calculated.
  5. Multiple this new number by 703.
  6. The resulting number is your BMI.

Here’s an example:

  1. A person weighs 150 pounds.
  2. He/She is 5 feet, 8 inches. This equals 68 inches.
  3. The square of 68 is 4,624. (In other words, 68 x 68.)
  4. 150 divided by 4,624 equals 0.0324.
  5. 0.0324 multiplied by 703 equals 22.8.
  6. This person’s BMI is 22.8.

In 2008, the estimated annual medical cost of obesity in the United States was $147 billion. The medical costs for people who were obese were on average $1,429 higher than those of persons of a healthy weight.

A multitude of conditions and diseases have been linked to obesity, including certain types of cancer, stroke, Type 2 diabetes, heart disease, back problems, foot problems, and others.

It’s crucial to understand that your BMI is just one indicator your physician uses in determining whether you are at a healthy weight. Discuss with your doctor what your acceptable weight range should be, as well as what potential health problems you could be at risk for if you are or become overweight or obese.

Please keep in mind that children and teens, ages 2 to 19, are held to a different BMI table. Children’s body compositions change rapidly as they grow, varying especially between boys and girls, therefore their BMIs are determined using age- and gender-specific percentiles.

Image by davidd via Flickr