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

3. Importance of BMI Calculation

Details: BMI provides the most useful population-level measure of overweight and obesity as it is the same for both sexes and for all ages of adults. However, it should be considered a rough guide because it may not correspond to the same degree of fatness in different individuals.

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., 175 cm = 1.75 m). All values must be valid (weight > 0, height > 0).

5. Frequently Asked Questions (FAQ)

Q1: What are the BMI categories for adults?
A: Underweight (<18.5), Normal weight (18.5-24.9), Overweight (25-29.9), Obese (≥30).

Q2: Is BMI accurate for everyone?
A: BMI may not be accurate for athletes (who may have high muscle mass), pregnant women, or the elderly (who may have lost muscle mass).

Q3: How often should I check my BMI?
A: For most adults, checking once a year is sufficient unless you're actively trying to lose or gain weight.

Q4: Does BMI differ for children?
A: Yes, BMI for children and teens is age- and sex-specific and is often referred to as BMI-for-age.

Q5: What's a healthy BMI range for Canadians?
A: The same ranges apply worldwide, but Health Canada recommends maintaining a BMI between 18.5 and 24.9 for optimal health.