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BMI Calculator Using Body Measurements

BMI Formula:

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

kg
meters

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1. What is BMI?

BMI (Body Mass Index) 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:

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

Where:

Explanation: The formula provides a simple numeric measure of a person's "fatness" or "thinness" allowing health professionals to discuss overweight and underweight problems more 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 most accurate results, measure weight in the morning before eating and after using the bathroom. Measure height without shoes.

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 those with muscular builds, and underestimate it in older persons who have lost muscle mass.

Q3: How often should I check my BMI?
A: For most adults, checking every 6-12 months is sufficient unless you're actively trying to lose or gain weight.

Q4: Can children use this calculator?
A: Children and teens need age- and sex-specific BMI percentiles rather than the adult categories.

Q5: What's a healthy BMI range?
A: For most adults, 18.5 to 24.9 is considered healthy, but individual factors like muscle mass and body frame should be considered.

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