Body Mass Index - For - Age

The body mass index is different for children than for adults therefore, the following formulas and tables must be used.

Step 1 Take your child’s height

Step 2 Take your child’s weight.

Step 3 Use the following formulas to obtain the BMI number

English Formula

Weight in pounds ÷ Height in Inches ÷ Height in Inches x 703 = BMI

Metric Formula

Weight in kilograms ÷ Height in meters ÷ Height in meters = BMI

Use appropriate BMI chart for boys and girls.

Step 5 Use chart to mark a point of child’s age versus his/her BMI. From the point interpolate (i.e. estimate between the curved lines) your child’s BMI percentile.

Boys Body Mass Index for age

Girls Body Mass Index for age

What does this mean for your Child?

BMI of less than the 5^th percentile. Child is underweight

BMI of greater than or equal to the 85^th percentile. Child is at risk of overweight

BMI of greater than or equal to the 95^th percentile. Child is overweight/obese

Reference

CDC Body Mass Index-for-Age (children).  www.cdc.gov/nccdphp/dnpa/bmi/bmi-for-age.htm

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