Since body fat is hard to measure directly, it is often measured by body mass index or BMI. According to obesityaction.org, BMI measures weight related to height. It is one tool healthcare providers use when talking about weight. BMI is not a percentage of body fat, it is only part of a diagnosis of obesity. For children age 2 and older and for teens, BMI uses weight and height, but adds sex and age into the calculation. Instead of using a specific number like the BMI charts for adults, the BMI for children and teens is listed as a percent. This percentage indicates a child’s BMI in relation to the BMIs of other children of the same sex and age.
Children age 2 and older are considered:
- At a healthy weight if their BMI falls between the 5th and the 85th percentiles
- Overweight if their BMI is between the 85th and 95th percentiles
- Obese if their BMI is at or higher than the 95th percentile BMI