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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, overweight and obesity in adults. It is defined as a person's weight in kilograms divided by the square of their height in meters (kg/m²).
The calculator uses the BMI formula:
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.
Details: BMI is a simple, inexpensive, and non-invasive surrogate measure of body fat. While it doesn't measure body fat directly, research has shown that BMI correlates to direct measures of body fat. It is used to screen for weight categories that may lead to health problems.
Tips: Enter weight in kilograms and height in meters. All values must be valid (weight > 0, height > 0). For best results, measure weight and height accurately.
Q1: What are the standard BMI categories?
A: Underweight: <18.5, Normal weight: 18.5-24.9, Overweight: 25-29.9, Obesity: ≥30.
Q2: Are there limitations to BMI?
A: Yes, BMI doesn't account for muscle mass, bone density, overall body composition, and racial and sex differences. Athletes may have a high BMI but not have excess body fat.
Q3: Is BMI applicable to everyone?
A: BMI may not be accurate for children, pregnant women, the elderly, and highly muscular individuals. Different approaches may be needed for these populations.
Q4: How often should I calculate my BMI?
A: For most adults, checking BMI once every few months is sufficient unless you're actively trying to change your weight.
Q5: Should BMI be the only measure of health?
A: No, BMI should be used as a screening tool, not a diagnostic of body fatness or health. Other factors like waist circumference, diet, and physical activity should also be considered.