1. What is the Mifflin-St Jeor Equation?

The Mifflin-St Jeor equation is currently considered the most accurate method for estimating basal metabolic rate (BMR) in healthy individuals. It accounts for weight, height, age, and gender to determine the number of calories your body needs at complete rest.

2. How Does the Calculator Work?

The calculator uses the Mifflin-St Jeor equation:

Where:

• \( weight \) — Body weight in kilograms (kg)
• \( height \) — Height in centimeters (cm)
• \( age \) — Age in years
• \( s \) — +5 for men, -161 for women

Explanation: The equation accounts for the fact that men typically have more muscle mass than women of the same weight, and that metabolism slows with age.

3. Importance of BMR Calculation

Details: Knowing your BMR helps determine your daily caloric needs for weight maintenance, loss, or gain. It's the foundation for all nutrition and weight management plans.

4. Using the Calculator

Tips: Enter weight in kg, height in cm, age in years, and select gender. For most accurate results, measure weight and height in the morning before eating.

5. Frequently Asked Questions (FAQ)

Q1: Why use Mifflin-St Jeor instead of Harris-Benedict?
A: The Mifflin-St Jeor equation is more accurate for modern populations, with an error rate of about 10% compared to indirect calorimetry.

Q2: What are normal BMR values?
A: Typical BMR ranges from 1200-2000 kcal/day for adults, but varies significantly based on body composition, age, and gender.

Q3: Does muscle mass affect BMR?
A: Yes, muscle tissue burns more calories at rest than fat tissue. Two people with the same weight but different body compositions will have different BMRs.

Q4: How does age affect BMR?
A: BMR typically decreases by 1-2% per decade after age 20, primarily due to loss of muscle mass.

Q5: Should this be used for athletes?
A: While still useful, athletes with very high muscle mass may need additional adjustments or direct measurement methods.