Body mass index (BMI), which measures weight in relation to height, is used to identify a possible weight problem for a child older than 2 years old.
A child age 2 to younger than 5 who has a BMI:
- Below the 3rd percentile is at risk for underweight.
- In the 3rd percentile to below the 85th percentile is at a healthy weight.
- In the 85th percentile to the 97th percentile is at risk for overweight.
- Above the 97th percentile to the 99.9th percentile is overweight.
- Above the 99th percentile is obese.
A child ages 5 to 19 who has a BMI:
- Below the 3rd percentile is at risk for underweight.
- In the 3rd percentile to below the 85th percentile is at a healthy weight.
- In the 85th percentile to the 97th percentile is overweight.
- Above the 97th percentile to the 99.9th percentile is obese.
- Above the 99th percentile is severely obese.
Children grow at a different rates. Your doctor can tell you if your child's weight is a concern.
In some cases, a child may be considered at risk for overweight or overweight because he or she has a large amount of body fat (adipose tissue). But not all children with BMIs in the 85th to 97th percentile have too much body fat. For instance:
- A child who has grown consistently at a higher percentile for most of his or her life may just be bigger than other children of the same age due to genetics.
- Before and during puberty, it is normal for children to have a significant gain in weight before beginning to grow in height. This can temporarily increase a child's BMI.
- Children who are very muscular (for instance, children who are very active in sports) may have a higher BMI but have normal or even low amounts of body fat.
Current as of: February 27, 2023
Author: Healthwise Staff
Medical Review:Adam Husney MD - Family Medicine & John Pope MD - Pediatrics & Thomas M. Bailey MD - Family Medicine & Kathleen Romito MD - Family Medicine & Martin J. Gabica MD - Family Medicine & Rhonda O'Brien MS, RD, CDE - Certified Diabetes Educator