Nutrition glossary
What Is BMR?
**BMR (Basal Metabolic Rate)** is the number of calories your body burns at complete rest just to stay alive — breathing, circulating blood, and running your organs. It makes up roughly 60–70% of your total daily energy expenditure.
It's the floor of your calorie needs before you take a single step, which is why it matters so much more than the calories you burn in the gym.
Short answer
BMR (Basal Metabolic Rate) is the number of calories your body burns at complete rest just to stay alive — breathing, circulating blood, and running your organs. It makes up roughly 60–70% of your total daily energy expenditure.
How it works
Even at rest, your body is busy: your heart pumps, your lungs work, your brain and organs draw constant energy. BMR captures all of it. Because it accounts for the majority of your burn, it's the largest component of your TDEE — far bigger than exercise.
Your BMR scales mainly with your size and how much lean tissue you carry. Muscle is metabolically active, so the more you have, the higher your BMR runs around the clock.
Why it matters for your goals
Because BMR is such a large share of your burn, protecting it protects your results. A long, aggressive diet can suppress it through metabolic adaptation — your body trims the cost of keeping you running to defend its weight.
Never set your calorie target below your BMR for any length of time. Eating under the energy your organs need accelerates muscle loss, drains your energy, and makes the metabolism push back harder.
Frequently asked questions
What is a normal BMR?
BMR varies widely with size, age, and sex, but most adults fall between roughly 1,300 and 1,900 calories per day. Larger people and those with more muscle sit higher.
Can I increase my BMR?
Modestly, yes. Building muscle through resistance training is the most reliable way, since muscle is metabolically active. Eating enough protein and avoiding prolonged crash diets also protects it.
Should I eat at my BMR to lose weight?
No. Eating at or below your BMR is too aggressive and risks muscle loss and fatigue. Build your deficit from your TDEE instead and keep your intake above your BMR.
Keep exploring
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