1. What is BMI for Children?

BMI (Body Mass Index) for children and teens is calculated the same way as for adults, but the interpretation is different. For children, BMI is age- and sex-specific and is often referred to as BMI-for-age.

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 BMI number must be plotted on CDC growth charts to determine the BMI-for-age percentile.

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.

4. Using the Calculator

Tips: Enter weight in kilograms, height in meters, age in years (between 2-19), and select gender. All values must be valid (weight > 0, height > 0, age 2-19).

5. Frequently Asked Questions (FAQ)

Q1: Why is BMI interpreted differently for children?
A: Children's body composition varies as they grow, and between boys and girls. BMI-for-age accounts for these differences.

Q2: What are the BMI categories for children?
A: Underweight (<5th percentile), Healthy weight (5th-85th), Overweight (85th-95th), Obese (≥95th percentile).

Q3: When should BMI be measured in children?
A: The American Academy of Pediatrics recommends BMI screening annually from age 2.

Q4: Are there limitations to BMI for children?
A: BMI doesn't distinguish between muscle and fat, and may not be accurate for very muscular children or those with certain medical conditions.

Q5: Where can I find CDC growth charts?
A: CDC growth charts are available on the CDC website for clinical use in interpreting BMI-for-age.