What is BMR? Basal Metabolic Rate (BMR) is the number of calories your body needs to accomplish its most basic (basal) life-sustaining functions. These functions include breathing, circulation, cell production, nutrient processing, protein synthesis, and ion transport. You can think of BMR as the amount of energy your body would burn if you stayed in bed all day and did absolutely nothing. BMR Formula This calculator uses the Mifflin-St Jeor equation, which is widely considered the most accurate formula for estimating BMR. For Men: BMR = (10 � weight in kg) + (6.25 � height in cm) - (5 � age in years) + 5 For Women: BMR = (10 � weight in kg) + (6.25 � height in cm) - (5 � age in years) - 161 What Variables Affect BMR? Muscle Mass: Muscle tissue burns more calories than fat tissue, even at rest. Age: BMR generally slows down as you get older, mainly due to a loss of muscle mass. Genetics: Your metabolic rate is partially determined by the genes you inherit. Weather: Cold environments force the body to burn more calories to stay warm, while hot environments can also increase BMR slightly. Diet: Starvation or severe calorie restriction can dramatically reduce BMR as the body attempts to conserve energy. Frequently Asked Questions What is the difference between BMR and RMR (Resting Metabolic Rate)? While often used interchangeably, BMR and RMR are slightly different. BMR is measured under strict, restrictive conditions (e.g., in a dark room upon waking after 8 hours of sleep and 12 hours of fasting). RMR is measured under less strictly controlled conditions. However, the resulting numbers are usually very similar. How do I use my BMR to lose weight? First, calculate your BMR. Then, multiply it by an activity factor (TDEE). Once you know your TDEE, subtract calories (typically 300-500 kcal/day) to create a calorie deficit, which leads to weight loss. Can I increase my BMR? Yes. The most effective way to organically increase your BMR is to build more lean muscle mass through strength or resistance training.
