1. What is BMI for Children?

BMI (Body Mass Index) for children and teens is age- and sex-specific and is often referred to as BMI-for-age. Unlike adults, children's BMI must be interpreted relative to other children of the same age and sex using CDC growth charts.

2. How Does the Calculator Work?

The calculator uses the standard BMI formula:

Where:

• \( weight \) — Body weight in kilograms
• \( height \) — Height in meters

Note: For children, the calculated BMI must be plotted on CDC growth charts to determine the BMI percentile, which indicates how the child's BMI compares to others of the same age and sex.

3. Importance of BMI Calculation

Details: BMI-for-age is the recommended measure for screening overweight and obesity in children and teens. It's a reliable indicator of body fatness for most children and teens, though it doesn't measure body fat directly.

4. Using the Calculator

Tips: Enter weight in kilograms, height in meters, age in years (2-19), and select gender. For accurate results, measurements should be taken with proper technique.

5. Frequently Asked Questions (FAQ)

Q1: What are the BMI categories for children?
A: CDC defines: Underweight (<5th percentile), Healthy weight (5th-<85th), Overweight (85th-<95th), Obese (≥95th percentile).

Q2: Why is BMI interpreted differently for children?
A: Children's body composition varies with age and differs between boys and girls, so BMI must be age- and sex-specific.

Q3: How often should children's BMI be checked?
A: The American Academy of Pediatrics recommends BMI screening annually for all children aged 2 years and older.

Q4: Are there limitations to BMI for children?
A: BMI doesn't distinguish between fat and muscle mass, so athletic children may have high BMI without excess fat. It's a screening tool, not a diagnostic.

Q5: Where can I find CDC growth charts?
A: CDC growth charts are available at https://www.cdc.gov/growthcharts/.