1. What is BMI?

Body Mass Index (BMI) is a measure of body fat based on height and weight that applies to both adult men and women as well as children and adolescents. For pediatric patients, BMI is compared to age- and sex-specific 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 formula calculates body mass per unit of height squared, providing a standardized measure for comparing individuals of different heights.

3. Importance of BMI Calculation for Children

Details: For children and teens, BMI is age- and sex-specific and is referred to as BMI-for-age. It's an important screening tool to identify possible weight problems but is not a diagnostic tool.

4. Using the Calculator

Tips: Enter weight in kilograms and height in meters. All values must be valid (weight > 0, height > 0). For pediatric patients, the result should be plotted on a growth chart or compared to percentiles.

5. Frequently Asked Questions (FAQ)

Q1: How is pediatric BMI different from adult BMI?
A: For children, BMI is compared to age- and sex-specific percentiles rather than using fixed categories as with adults.

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

Q3: Why use BMI for children?
A: BMI is a reliable indicator of body fatness for most children and teens, though it may overestimate body fat in muscular children.

Q4: Are there limitations to BMI for children?
A: BMI doesn't directly measure body fat and can be influenced by factors like muscle mass, bone density, and puberty stage.

Q5: How often should children's BMI be measured?
A: The American Academy of Pediatrics recommends BMI calculation at least annually as part of routine health supervision.