Child BMI (BMI-for-age) accounts for age and gender differences in body fat, making it more appropriate than adult BMI for growing children. However, BMI is a screening tool — it does not directly measure body fat. A healthcare provider should perform a full assessment.
According to the CDC, a healthy weight for children is between the 5th and 85th percentile for their age and gender. Below the 5th percentile is considered underweight, while at or above the 95th percentile is considered obese.
Consult your pediatrician before making any dietary changes. For growing children, the focus should be on healthy habits — balanced nutrition, regular physical activity, and adequate sleep — rather than weight loss, which can interfere with normal development.