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Determining Body Mass Index
Programs related to this topic
Endocrinology Program   Optimal Weight for Life (OWL) Program  
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:
  • Take your adolescent's weight in pounds and divide by 2.2 to determine his/her weight in kilograms. This is the "weight number."
  • Next, convert your adolescent's height in inches into height in centimeters by multiplying the number of inches by 2.54.

    • Divide your adolescent's height in centimeters by 100 (there are 100 centimeters per meter).
    • Next, square your adolescent's height in meters by multiplying the sum by itself. This number is the "height number."
  • Now, divide your adolescent's weight number by your adolescent's height number.
A BMI between 25-29 is considered overweight. Anything over 30 is considered obese.
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