1. What is BMI For Children?

BMI-for-age is a measure that adjusts BMI for a child's age and sex, as children's body composition varies as they grow. In New Zealand, this is compared against growth charts specific to the population.

2. How Does the Calculator Work?

The calculator uses the standard BMI formula adjusted for age and gender:

Where:

• \( weight \) — Body weight in kilograms
• \( height \) — Height in meters
• Age — Between 2-19 years
• Gender — Biological sex for growth chart comparison

Note: Interpretation requires NZ-specific growth charts which categorize BMI into percentiles.

3. Importance of BMI Calculation

Details: BMI-for-age helps identify children who are underweight, healthy weight, overweight or obese. Early identification allows for timely intervention.

4. Using the Calculator

Tips: Enter weight in kg, height in meters, exact age (2-19 years), and gender. For accurate results, measurements should be taken with minimal clothing and no shoes.

5. Frequently Asked Questions (FAQ)

Q1: Is BMI accurate for all children?
A: BMI is a screening tool but may not reflect body fatness in muscular children or those with different body compositions.

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

Q3: How often should children's BMI be checked?
A: Annual checks are recommended, or more frequently if there are concerns about growth patterns.

Q4: Are there ethnic considerations in NZ?
A: Yes, growth patterns may differ between Māori, Pacific, and European children. Specific charts may be used.

Q5: What if my child's BMI is outside the normal range?
A: Consult with a healthcare provider for a comprehensive assessment and guidance.