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The Heart Foundation BMI Calculator

BMI Formula:

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

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meters

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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:

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

Where:

Interpretation: The resulting number is then compared against standard BMI categories.

3. Importance of BMI Calculation

Details: 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. It is used to screen for weight categories that may lead to health problems.

4. Using the Calculator

Tips: Enter weight in kilograms and height in meters. For accurate results, measure weight without heavy clothing and height without shoes. All values must be valid (weight > 0, height > 0).

5. Frequently Asked Questions (FAQ)

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

Q2: Is BMI accurate for everyone?
A: BMI may not accurately reflect body fat in athletes (who have more muscle) or elderly (who may have lost muscle).

Q3: How often should I check my BMI?
A: For most adults, checking BMI annually is sufficient unless actively trying to lose or gain weight.

Q4: Should children use this calculator?
A: No, children and teens need age- and sex-specific BMI percentiles, not adult categories.

Q5: What's a healthy BMI range?
A: For most adults, 18.5 to 24.9 is considered healthy, but individual factors may affect this.

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