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BMI Formula:
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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.
The calculator uses the 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 objectively with their patients.
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.
Tips: Enter weight in kilograms and height in meters. For accurate results, measure weight without heavy clothing and height without shoes. All values must be valid (weight > 0, height > 0).
Q1: What are the BMI categories for adults?
A: Underweight (BMI < 18.5), Normal weight (18.5-24.9), Overweight (25-29.9), and Obese (≥30).
Q2: Is BMI different for women and men?
A: The BMI calculation is the same for both sexes, but the interpretation may differ slightly as women typically have more body fat than men at the same BMI.
Q3: What are the limitations of BMI?
A: BMI doesn't account for muscle mass, bone density, overall body composition, and racial/ethnic differences. Athletes may have a high BMI due to increased muscle mass rather than fat.
Q4: Is BMI accurate for pregnant women?
A: No, BMI should not be calculated during pregnancy as weight gain is expected and necessary for fetal development.
Q5: How often should I check my BMI?
A: For most adults, checking BMI once or twice a year is sufficient unless you're actively trying to lose or gain weight.