Question 1

What is BMR and why is it important?

Accepted Answer

BMR (Basal Metabolic Rate) is the number of calories your body burns at complete rest to maintain vital functions like breathing, circulation, cell production, and organ function. It typically accounts for 60-75% of your total daily calorie expenditure. Knowing your BMR is essential for creating effective weight loss or gain plans, as it forms the baseline for calculating your total daily energy needs.

Question 2

What is the difference between BMR and RMR?

Accepted Answer

BMR (Basal Metabolic Rate) measures calories burned at complete rest in a controlled environment after fasting and sleep. RMR (Resting Metabolic Rate) is measured under less strict conditions and is typically 10-20% higher than BMR. For practical purposes, they are often used interchangeably, though RMR is more commonly measured in clinical settings as it's easier to obtain.

Question 3

Which BMR formula is most accurate?

Accepted Answer

The Mifflin-St Jeor equation is considered the most accurate for most people, with studies showing it predicts measured BMR within 10% for the majority of individuals. The Harris-Benedict equation, developed in 1919, tends to overestimate BMR. The Katch-McArdle formula is most accurate for lean, athletic individuals when body fat percentage is known, as it accounts for lean body mass.

Question 4

What factors affect my BMR?

Accepted Answer

Several factors influence BMR: Age (BMR decreases about 2% per decade after 20), Gender (men typically have higher BMR due to more muscle mass), Body composition (more muscle means higher BMR), Genetics, Hormones (especially thyroid hormones), Body size (larger bodies require more energy), and Environmental temperature. Regular strength training can increase BMR by building muscle mass.

Question 5

How do I use my BMR to lose or gain weight?

Accepted Answer

To use BMR for weight management, first multiply it by an activity factor (1.2-1.9) to get your Total Daily Energy Expenditure (TDEE). For weight loss, eat 500 calories below TDEE to lose about 1 pound per week. For weight gain, eat 500 calories above TDEE. Never eat below your BMR, as this can slow metabolism and cause muscle loss. Always consult a healthcare provider before starting any diet plan.

BMR Calculator

Formula Comparison

Recommendation

Understanding BMR Formulas

Mifflin-St Jeor (1990) - Most Accurate

Harris-Benedict (1919) - Original

Katch-McArdle - For Athletes