CHOC Children's
ADOLESCENT MEDICINE :: Weight Management

Determining Body Mass Index

What is body mass index?

Determining how much your adolescent should weigh is not a simple matter of looking at an insurance height-weight chart, but includes considering the amount of bone, muscle, and fat in his/her body's composition. The amount of fat is the critical measurement.

A good indicator of how much fat your adolescent carries is the Body Mass Index (BMI). Although it is not a perfect measure, it gives a fairly accurate assessment of how much of your adolescent's body is composed of fat.

To calculate your BMI using the English formula:

BMI can be calculated using pounds and inches.

BMI = Weight in Pounds x 703
(Height in Inches) x (Height in Inches)

For example, a person who weighs 165 pounds and is 5 feet 4 inches tall has a BMI of 28.

165 lbs x 703 = 28
(64 inches) x (64 inches)

To calculate your BMI using the Metric formula:

BMI can be calculated using kilograms and meters.

BMI = Weight in Kilograms
(Height in Meters) x (Height in Meters)

For example, a person who weighs 99.79 Kilograms and is 1.905 Meters tall has a BMI of 27.5.

99.79 Kg = 27.5
(1.905 Meters) x (1.905 Meters)

A BMI between 25 to 29 is considered overweight. Anything over 30 is considered obese.

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Online Resources of Adolescent Medicine


It is important to remember the health information found on this website is for reference only not intended to replace the advice and guidance of your healthcare provider. Always seek the advice of your physician with any questions you may have regarding a medical condition. If you think you may have a medical emergency, call your physician or 911 immediately.

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