Obesity means having too much body fat. It is not the same as overweight, which means weighing too much. Obesity is becoming much more common in childhood. Most often, it begins between the ages of 5 and 6 and in adolescence.
Child health experts recommend that children be screened for obesity at age 2. If needed, they should be referred to weight-management programs.
Your child's mass index (BMI) is calculated using height and weight. A health care provider can use BMI to estimate how much body fat your child has.
However, measuring body fat and diagnosing obesity in children is different than measuring these things in adults. In children:
A BMI level that says a child is obese at one age may be normal for a child at a different age. To determine if a child is overweight or obese, experts compare BMI levels of children at the same age to each other. They use a special chart to decide whether a child’s weight is healthy or not.