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BMI Formula:
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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's calculated by dividing weight in kilograms by height in meters squared.
The calculator uses the standard BMI formula:
Where:
Explanation: The formula provides a simple numeric measure of a person's thickness or thinness, allowing health professionals to discuss weight problems more objectively with their patients.
Details: BMI provides a useful population-level measure of overweight and obesity as it's 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 body fat percentage in different individuals.
Tips: Enter weight in kilograms and height in meters (5 feet 9 inches = 1.75 meters). Age is optional but can provide context for interpretation. All values must be valid (weight > 0, height > 0).
Q1: What is a healthy BMI range?
A: For most adults, 18.5 to 24.9 is considered healthy. Below 18.5 is underweight, 25-29.9 is overweight, and 30+ is obese.
Q2: Does BMI apply to everyone?
A: BMI may not be accurate for athletes (who may have high muscle mass), pregnant women, the elderly, or children (who need age-specific charts).
Q3: How does age affect BMI interpretation?
A: Older adults may have a slightly higher BMI range considered healthy compared to younger adults due to natural body composition changes.
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: Should BMI be the only measure of health?
A: No, BMI should be considered alongside other measurements like waist circumference, body composition, and overall health indicators.