1. What is BMI for Children?

BMI (Body Mass Index) is a screening tool for weight categories in children and teens. For girls aged 2-20, BMI is age- and sex-specific and is plotted on CDC growth charts to determine weight-for-height percentiles.

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 compared against CDC growth charts for girls aged 2-20 to determine the weight-for-height percentile.

3. Importance of BMI Calculation

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

4. Using the Calculator

Tips: Enter weight in kg, height in meters, and exact age (2-20 years). For accurate results, measure height without shoes and weight with minimal clothing.

5. Frequently Asked Questions (FAQ)

Q1: Why use BMI-for-age instead of regular BMI?
A: Children's body composition varies with age and differs between boys and girls. BMI-for-age accounts for these normal growth patterns.

Q2: What are healthy BMI percentiles for girls?
A: 5th to 85th percentile is considered healthy weight. Below 5th is underweight, 85th-95th is overweight, and ≥95th is obese.

Q3: How often should BMI be checked in children?
A: The American Academy of Pediatrics recommends BMI screening annually starting at age 2.

Q4: Are there limitations to BMI for children?
A: BMI doesn't distinguish between fat and muscle mass. Athletic children may have high BMI due to muscle rather than fat.

Q5: What if my child's BMI is high?
A: Consult a pediatrician. They may assess other factors like growth pattern, family history, and diet/physical activity habits.