1. What is BMI for Children?

BMI (Body Mass Index) for children is calculated the same way as for adults, but the interpretation is different. Children's BMI is compared to growth charts to determine percentiles based on age and sex, as their body composition changes with growth.

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 is then compared to growth charts to determine the percentile for their age and sex.

3. Importance of BMI Calculation for Kids

Details: Tracking BMI in children helps identify potential weight problems early. Unlike adults, children's BMI must be interpreted relative to other children of the same age and sex.

4. Using the Calculator

Tips:

• Measure height without shoes
• Use current weight without heavy clothing
• Enter exact age in years
• For most accurate results, use measurements taken by a healthcare professional

5. Frequently Asked Questions (FAQ)

Q1: Why is BMI different for children than adults?
A: Children's body composition changes as they grow, so their BMI must be compared to others of the same age and sex.

Q2: What BMI percentile is considered healthy?
A: Generally, 5th to 85th percentile is considered healthy weight, 85th-95th is overweight, and above 95th is obese.

Q3: How often should my child's BMI be checked?
A: The NHS recommends annual BMI checks for school-age children as part of the National Child Measurement Programme.

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

Q5: Where can I get official NHS growth charts?
A: NHS growth charts are available at RCPCH website or through your GP.