1. What is BMI for Children?

BMI-for-age is the measure used for children and teens aged 2-19 years. Unlike adults, children's BMI is age- and sex-specific because their body composition varies as they grow. The CDC provides growth charts to interpret BMI results.

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 raw BMI number must be plotted on CDC growth charts to determine the BMI percentile which indicates weight status.

3. Importance of BMI Calculation

Details: BMI screening for children can identify potential weight problems, but is not a diagnostic tool. Healthcare providers use additional assessments to evaluate health status.

4. Using the Calculator

Tips: Enter weight in kilograms, height in meters, age in years (2-19), 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 fat changes with age and differs between boys and girls, so BMI must be interpreted relative to other children of the same age and sex.

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

Q3: How often should children's BMI be checked?
A: The AAP recommends BMI screening annually from age 2, with more frequent monitoring if concerns arise.

Q4: Are there limitations to BMI for children?
A: BMI doesn't distinguish between fat and muscle mass, and may be less accurate for very muscular children or those with certain medical conditions.

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