1. What is BMI for Children?

Body Mass Index (BMI) is a screening tool for overweight and obesity in children and teens. For children, BMI is age- and sex-specific and is often referred to as BMI-for-age. Unlike adults, children's BMI must be compared against growth charts to determine weight status.

2. How Does the Calculator Work?

The calculator uses the standard BMI formula adjusted for children:

Where:

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

Explanation: The result is compared to CDC growth charts to determine the percentile for the child's age and sex.

3. Importance of BMI Calculation

Details: Tracking BMI-for-age helps identify potential weight problems that may lead to health issues. Early identification allows for early intervention.

4. Using the Calculator

Tips: Enter weight in kilograms, height in meters, age in years (2-20), and select gender. For accurate results, measure height and weight carefully.

5. Frequently Asked Questions (FAQ)

Q1: Why is BMI different for children than adults?
A: Children's body composition varies by age and sex as they grow. BMI-for-age accounts for these normal growth patterns.

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

Q3: How often should my child's BMI be checked?
A: The AAP recommends BMI screening at least annually starting at age 2.

Q4: Does BMI diagnose obesity in children?
A: BMI is a screening tool, not a diagnostic. Further assessment is needed to determine if excess fat is a problem.

Q5: Are there limitations to BMI for children?
A: BMI doesn't distinguish between muscle and fat, and may not reflect body fat distribution. It's one part of a complete health assessment.