1. What is BMI for Children and Teens?

BMI (Body Mass Index) is a screening tool for weight categories in children and teens aged 2-19 years. For this age group, BMI is age- and sex-specific and is 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

Explanation: The result is compared to CDC growth charts for girls to determine the weight status percentile.

3. Importance of BMI Calculation

Details: BMI-for-age is the recommended measure for screening overweight and obesity in children and teens because it accounts for normal differences in body fat between boys and girls and differences at various ages.

4. Using the Calculator

Tips: Enter weight in kilograms, height in meters, and age between 2-19 years. For accurate results, measurements should be taken with minimal clothing and no shoes.

5. Frequently Asked Questions (FAQ)

Q1: Why use BMI-for-age instead of regular BMI?
A: Children's body composition varies as they grow, so BMI must be interpreted relative to other children of the same sex and age.

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

Q3: How often should BMI be calculated for children?
A: The American Academy of Pediatrics recommends BMI calculation at least annually.

Q4: Are there limitations to BMI?
A: BMI doesn't directly measure body fat and may misclassify muscular children. It should be used as a screening tool, not a diagnostic.

Q5: Where can I find the official growth charts?
A: CDC growth charts are available at: https://www.cdc.gov/growthcharts/