What is BMR?
Basal Metabolic Rate (BMR) is the number of calories your body needs to perform basic life-sustaining functions — such as breathing, circulation, cell production, and maintaining body temperature — while at complete rest. It represents the minimum energy required to keep you alive.
Mifflin-St Jeor Equation
Men: BMR = 10W + 6.25H − 5A + 5
Women: BMR = 10W + 6.25H − 5A − 161
W = weight (kg) | H = height (cm) | A = age (years)
Women: BMR = 10W + 6.25H − 5A − 161
W = weight (kg) | H = height (cm) | A = age (years)
The Mifflin-St Jeor equation (1990) is considered the most accurate formula for estimating BMR in most adults.
Factors That Affect BMR
- Age: BMR decreases by approximately 2% per decade after age 20
- Muscle mass: More muscle = higher BMR (muscle burns more calories than fat)
- Genetics: Some people naturally have faster or slower metabolisms
- Hormones: Thyroid hormones, in particular, strongly regulate metabolic rate
- Body temperature: BMR increases when you're ill or in cold environments