1. What is BMI?

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 the weight in kilograms divided by the square of the height in meters.

2. How Does the Calculator Work?

The calculator uses the standard BMI formula:

Where:

• \( weight \) — Body weight in kilograms
• \( height \) — Height in meters

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.

3. Importance of BMI Calculation

Details: BMI is a simple, inexpensive, and noninvasive 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.

4. Using the Calculator

Tips: Enter weight in kilograms, height in meters, and age in years. All values must be valid (weight > 0, height > 0, age ≥18).

5. Frequently Asked Questions (FAQ)

Q1: What are the standard BMI categories?
A: Underweight (<18.5), Normal weight (18.5-24.9), Overweight (25-29.9), Obese (≥30).

Q2: Is BMI accurate for everyone?
A: BMI may overestimate body fat in athletes and those with muscular builds, and underestimate body fat in older persons who have lost muscle mass.

Q3: Why is age included in this calculator?
A: While BMI interpretation is generally the same for all adults, some age-related considerations exist for older adults.

Q4: What are the limitations of BMI?
A: BMI doesn't account for muscle mass, bone density, overall body composition, or racial and sex differences.

Q5: Should BMI be the only measure of healthy weight?
A: No, waist circumference and other risk factors should be considered along with BMI for a complete assessment.