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BMI Calculator

BMI Formula:

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

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meters

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1. What is BMI?

BMI (Body Mass Index) is a simple calculation using a person's height and weight. The formula is BMI = kg/m² where kg is a person's weight in kilograms and m² is their height in meters squared. BMI screens for weight categories that may lead to health problems.

2. How Does the Calculator Work?

The calculator uses the BMI formula:

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

Where:

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. Importance of BMI Calculation

Details: BMI is a useful screening tool to identify possible weight problems for adults. However, it is not a diagnostic tool. BMI 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. All values must be valid (weight > 0, height > 0). For pounds and inches, convert first (1 kg = 2.2 lbs, 1 m = 39.37 inches).

5. Frequently Asked Questions (FAQ)

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

Q2: Is BMI accurate for everyone?
A: BMI may overestimate body fat in athletes and those with muscular build, and underestimate it in older persons who have lost muscle mass.

Q3: Should children use this calculator?
A: No, children and teens need age- and sex-specific percentiles because their body composition varies as they grow.

Q4: What are the limitations of BMI?
A: BMI doesn't distinguish between muscle and fat, doesn't account for fat distribution, and may not be accurate for certain ethnic groups.

Q5: What's a healthy BMI range?
A: For most adults, 18.5 to 24.9 is considered healthy, but individual health assessments should consider other factors too.

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