1. What is BMI?

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 is defined as a person's weight in kilograms divided by the square of their height in meters (kg/m²).

2. How Does the Calculator Work?

The calculator uses the standard BMI formula:

Where:

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

Explanation: The formula calculates body mass per unit of surface area, providing a standardized measure for comparing individuals of different heights.

3. Importance of BMI Calculation

Details: BMI is a simple, inexpensive screening tool for weight categories that may lead to health problems. It helps identify potential weight problems for adults, though it doesn't diagnose body fatness or health.

4. Using the Calculator

Tips: Enter weight in kilograms, height in meters, age in years, and select gender. For accurate results, measure height without shoes and weight with minimal clothing.

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), Obese (≥30).

Q2: Does BMI interpretation differ by age or gender?
A: While the same BMI values apply to all adults, body composition varies by age and gender. Older adults may have higher BMI due to reduced muscle mass.

Q3: What are the limitations of BMI?
A: BMI doesn't distinguish between muscle and fat mass, so athletes may have high BMI without excess fat. It also doesn't account for fat distribution.

Q4: Is BMI different for children?
A: Yes, children's BMI is age and sex-specific and interpreted using percentile charts rather than fixed categories.

Q5: What's a healthy BMI for older adults?
A: For those over 65, a BMI between 23-30 may be healthier than lower values, as some extra weight can protect against osteoporosis and other conditions.