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Body Mass Index (BMI)

By , About.com Guide

Updated January 04, 2009

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Definition: BMI is a method of calculating how much you should weigh, based upon your height. A BMI of 18.5 to 25 is considered healthy. Below 18.5 is considered underweight, above 25 is considered overweight and a BMI higher than 30 is obese.

BMI is not accurate in very muscular individuals who may be very heavy for their height, but do not have high levels of fat.

Calculate your BMI in 5 steps

1. Convert your weight in pounds to kilograms by dividing by 2.2

2. Convert your height in feet to inches (1 foot = 12 inches).

3. Convert your height to meters: multiply your height in inches by 2.54. Then divide by 100.

4. Multiply your height (in meters) by itself.

5. Divide your weight in kilograms (step 1) by your height squared (step 4).

The result of step 5 is your BMI.

Related Information: All About Weight Loss Surgery

Also Known As: Body Mass Index
Examples:
After calculating her BMI she realized that she did not need to lose weight.

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