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 defined as the weight in kilograms divided by the square of the height in meters (kg/m²).

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 across different heights.

3. Indian-specific BMI Cutoffs

Details: For Indian population, lower BMI cutoffs are used due to higher body fat percentage at lower BMI levels compared to Caucasians:

• Underweight: < 18.5 kg/m²
• Normal weight: 18.5-23 kg/m²
• Overweight: >23 kg/m² (vs >25 for Caucasians)
• Obese: >25 kg/m² (vs >30 for Caucasians)

4. Using the Calculator

Tips: Enter weight in kilograms and height in meters. For height, you can convert from cm to m by dividing by 100 (e.g., 170 cm = 1.7 m). All values must be valid (weight > 0, height > 0).

5. Frequently Asked Questions (FAQ)

Q1: Why different cutoffs for Indians?
A: Indians have higher body fat percentage at lower BMI levels compared to Caucasians, increasing health risks at lower BMI thresholds.

Q2: What are limitations of BMI?
A: BMI doesn't distinguish between muscle and fat mass. Athletes may have high BMI due to muscle, while some with normal BMI may have excess body fat.

Q3: Is BMI different for males and females?
A: The calculation is the same, but women typically have higher body fat percentage than men at the same BMI.

Q4: What's a healthy BMI range for Indians?
A: For Indians, 18.5-23 kg/m² is considered healthy, with increased health risks above 23 kg/m².

Q5: Should BMI be the only measure of health?
A: No, waist circumference and body fat percentage provide additional important information about health risks.