1. What is BMI?

Body Mass Index (BMI) is a simple index of weight-for-height that is commonly used to classify underweight, normal weight, overweight and obesity in adults. It is calculated by dividing a person's weight in kilograms by the square of their height in meters.

2. How Does the Calculator Work?

The calculator uses the standard BMI formula:

Where:

• \( weight \) — Body weight in kilograms (kg)
• \( height \) — Height in meters (m)

Explanation: BMI provides a simple numeric measure of a person's thickness or thinness, allowing health professionals to discuss weight problems more objectively with their patients.

3. Asia Pacific BMI Classification

Details: The Asia Pacific classification differs from WHO standards due to higher risk of metabolic complications at lower BMI levels in Asian populations.

Classification:

• < 18.5 kg/m² — Underweight
• 18.5-22.9 kg/m² — Normal
• 23-24.9 kg/m² — Overweight (At Risk)
• 25-29.9 kg/m² — Overweight (Moderately Obese)
• ≥ 30 kg/m² — Overweight (Severely Obese)

4. Using the Calculator

Tips: Enter weight in kilograms and height in meters. For height in centimeters, divide by 100 (e.g., 175 cm = 1.75 m). All values must be valid (weight > 0, height > 0).

5. Frequently Asked Questions (FAQ)

Q1: Why different BMI categories for Asians?
A: Asian populations develop metabolic complications at lower BMI levels than Caucasians, hence the adjusted categories.

Q2: What are limitations of BMI?
A: BMI doesn't distinguish between muscle and fat mass, so athletes may be misclassified. It also doesn't account for fat distribution.

Q3: Is BMI different for children?
A: Yes, children's BMI is age and sex-specific and interpreted using percentile charts.

Q4: What's the ideal BMI for Asians?
A: For Asians, the ideal range is 18.5-22.9 kg/m², with increased health risks above 23 kg/m².

Q5: Should BMI be the only measure of health?
A: No, waist circumference and other health markers should also be considered for a complete assessment.