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Bmi Calculator National Institute Of Health Nih

BMI Equation:

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

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meters

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1. What is BMI?

BMI (Body Mass Index) is a person's weight in kilograms divided by the square of height in meters. It's a simple screening tool for weight categories that may lead to health problems.

2. How Does the Calculator Work?

The calculator uses the standard BMI formula:

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

Where:

Explanation: The formula calculates body mass per unit of height squared, providing a standardized measure of body composition.

3. Importance of BMI Calculation

Details: BMI is an inexpensive screening tool for weight categories that may indicate underweight, healthy weight, overweight, and obesity. While it doesn't directly measure body fat, it correlates with more direct measures of body fat.

4. Using the Calculator

Tips: Enter weight in kilograms and height in meters. For pounds and inches, first convert to metric units (1 kg = 2.2 lbs, 1 m = 39.37 inches).

5. Frequently Asked Questions (FAQ)

Q1: What are the standard 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 underestimate it in older people with lost muscle mass.

Q3: What is a healthy BMI range?
A: For most adults, 18.5 to 24.9 is considered healthy.

Q4: Should children use this calculator?
A: No, children and teens need age- and sex-specific BMI percentiles.

Q5: What are the health risks of high BMI?
A: Higher BMI increases risk of heart disease, diabetes, and certain cancers.

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