1. What is BMI for Children and Teens?

BMI (Body Mass Index) is a measure that uses height and weight to estimate body fat. For children and teens, BMI is age- and sex-specific and is referred to as BMI-for-age. The NSW tool compares the calculated BMI with growth charts to determine the percentile.

2. How Does the Calculator Work?

The calculator uses the standard BMI formula:

Where:

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

Explanation: The result is then compared to NSW growth charts to determine the child's BMI percentile based on age and gender.

3. Importance of BMI Calculation

Details: BMI-for-age is the recommended measure for screening overweight and obesity in children and teens. It helps identify potential weight problems that may lead to health issues.

4. Using the Calculator

Tips: Enter weight in kilograms, height in meters, age in years (2-18), and select gender. For accurate results, measurements should be taken with minimal clothing and no shoes.

5. Frequently Asked Questions (FAQ)

Q1: Why is BMI different for children than adults?
A: Children's body composition varies with age and sex, so BMI must be interpreted relative to growth charts.

Q2: What do the percentile ranges mean?
A: Generally, <5th percentile is underweight, 5th-85th is healthy weight, 85th-95th is overweight, and ≥95th is obese.

Q3: When should I be concerned about my child's BMI?
A: Consult a healthcare provider if your child is below 5th percentile or above 85th percentile consistently.

Q4: Are there limitations to BMI for children?
A: BMI doesn't distinguish between muscle and fat, so athletic children may have high BMI without excess fat.

Q5: How often should my child's BMI be checked?
A: Annual checks are typically sufficient unless recommended otherwise by a healthcare provider.