Once a person has determined their BMI from the obesity chart, the next step is to interpret the results.  Interpretation of the BMI results is different for adults and children under the age of 20.

 

For adults 20 years and older, the BMI results are interpreted using standard weight status categories that are the same for all ages and for both men and women. The standard weight status categories associated with the BMI results for adults are shown in the following table.

 

 

The obesity chart provides only the BMI number and not the BMI age- and sex-specific percentile that is used to interpret BMI and determine the weight category for children and teens. It is not appropriate to use the BMI categories for adults to interpret BMI numbers for children and teens. Instead, for children and teens, after determining the BMI, the BMI number is plotted on the BMI-for-age growth charts (for either girls or boys) to obtain a percentile ranking. The percentile indicates the relative position of the child's BMI number among children of the same sex and age.

 

 

BMI-for-age weight status categories and the corresponding percentiles are shown in the following table.