You burn approximately 40 to 55 calories per hour while sleeping, with an average estimate around 50 calories per hour. Over an 8-hour sleep period, this totals roughly 320 to 440 calories burned during sleep
. The exact number varies based on factors such as your basal metabolic rate (BMR), age, weight, sex, and overall health. People with higher body weight or muscle mass tend to burn more calories even while resting or sleeping
. Most calorie burning during sleep occurs because your body continues vital functions like breathing, circulation, brain activity, and cellular repair. Notably, REM sleep burns the most calories among sleep stages due to increased brain activity and heart rate during dreaming
. To estimate your personal calories burned while sleeping, you can calculate your BMR and then multiply by the hours slept and a factor to account for reduced metabolism during sleep (about 85% of awake resting calories):
Calories burned sleeping=BMR24×hours asleep×0.85\text{Calories burned sleeping}=\frac{\text{BMR}}{24}\times \text{hours asleep}\times 0.85Calories burned sleeping=24BMR×hours asleep×0.85
This formula provides a rough estimate tailored to individual characteristics
. In summary:
- Average calories burned sleeping: ~50 calories/hour
- For 8 hours: ~400 calories burned
- Influenced by BMR, weight, age, sex, and sleep stage
- REM sleep burns the most calories during sleep
