How Do You Calculate BMI For Children

BMI Formula:

\[ BMI = \frac{weight\ (kg)}{[height\ (m)]^2} \]

Weight:

Height:

meters

Age:

years

Gender:

BMI:

Percentile (Estimate):

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1. What Is BMI For Children?

BMI (Body Mass Index) for children is a measure that adjusts weight for height, compared to age- and gender-specific percentiles from growth charts. Unlike adults, children's BMI must be interpreted relative to other children of the same age and sex.

2. How To Calculate BMI For Children?

The calculator uses the standard BMI formula:

\[ BMI = \frac{weight\ (kg)}{[height\ (m)]^2} \]

Where:

\( weight \) — Body weight in kilograms
\( height \) — Height in meters

Explanation: The result is then plotted on CDC growth charts to determine the percentile for the child's age and gender.

3. Importance Of BMI Calculation

Details: BMI percentile is the most common indicator of weight status in children aged 2-20 years. It helps identify underweight, healthy weight, overweight, and obesity.

4. Using The Calculator

Tips: Enter weight in kilograms, height in meters, age in years (2-20), and select gender. For accurate results, measurements should be taken with minimal clothing.

5. Frequently Asked Questions (FAQ)

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

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

Q3: At what age can you start calculating BMI?
A: BMI is meaningful starting at age 2. For younger children, weight-for-length charts are used.

Q4: How often should children's BMI be checked?
A: Annually is recommended, or more frequently if there are concerns about growth patterns.

Q5: Are there limitations to BMI for children?
A: BMI doesn't distinguish between fat and muscle mass, so athletic children may have high BMI without excess fat.