How Many Calories Can You Burn Sleeping

The average person burns between 40 and 55 calories per hour while sleeping. Over a typical 7 to 9-hour sleep cycle, this adds up to 280 to 500 calories, depending on your weight, metabolism, and sleep quality. While that might sound surprising, it makes sense even when asleep, your body is actively working to maintain vital functions like breathing, circulating blood, regulating temperature, and repairing cells.

So, although sleep is a passive state, it still requires energy, and that energy comes from calorie expenditure.

Factors That Influence Calories Burned During Sleep

Your basal metabolic rate (BMR) is the biggest factor in how many calories you burn at rest, including during sleep. BMR is determined by a range of variables including age, sex, weight, muscle mass, genetics, and hormonal function. The more muscle you have, for example, the higher your resting energy needs, and the more calories you’ll burn while sleeping.

Sleep quality also plays a role. People who get deep, uninterrupted sleep are more likely to have steady hormonal activity, including the regulation of leptin and ghrelin, two hormones involved in hunger and metabolism. Poor sleep, on the other hand, can lower metabolic rate and contribute to fat gain over time.

Does Burning Calories While Sleeping Help With Weight Loss?

Technically, yes, the body burns a significant number of calories during sleep, and these calories contribute to your total daily energy expenditure (TDEE). However, you can’t rely on sleep alone to create a calorie deficit. For fat loss, the key is to burn more calories than you consume over a 24-hour period, which includes calories burned through sleep, physical activity, digestion, and everyday movements.

That said, high-quality sleep supports fat loss by helping regulate appetite, boost insulin sensitivity, and optimise hormones involved in energy use and fat storage. So, while it’s not a fat-burning powerhouse on its own, sleep is an essential part of any successful weight loss plan.

How Sleep Affects Your Body Composition

Good sleep not only burns calories, but also helps with muscle recovery, tissue repair, and growth hormone release all of which are crucial if you’re trying to build or preserve lean muscle while losing fat. In contrast, chronic sleep deprivation is linked to increased belly fat, lower energy levels, and a greater risk of overeating due to disrupted hunger cues.

In other words, sleep is not just about burning calories, it’s also about creating the right hormonal environment for your body to function efficiently and stay lean.

Can You Increase the Calories You Burn While Sleeping?

You can’t directly change how much you burn during sleep, but you can influence your BMR through lifestyle choices. Building more lean muscle mass through resistance training is the most effective way to increase the number of calories you burn both awake and asleep. Improving your sleep quality by sticking to a regular schedule, limiting caffeine, and reducing stress also helps your body maintain a higher, more consistent metabolic rate overnight.

Being well-rested also helps you make better food and exercise choices during the day, so sleep indirectly supports a higher overall calorie burn by keeping you more active and disciplined.

Calorie Burn While Sleeping Varies by Body Weight

The more you weigh, the more energy your body requires even at rest. A 60kg person might burn around 38–42 calories per hour of sleep, while someone weighing 90kg could burn closer to 55–60 calories per hour. That’s because a larger body requires more effort to maintain core temperature, organ function, and circulation, even during deep sleep.

So, while sleep burns calories for everyone, the exact amount scales with size and lean mass.

Deep Sleep Burns More Than Light Sleep

Not all sleep is equal in terms of energy use. REM sleep, the phase where most dreaming occurs involves increased brain activity, elevated heart rate, and even small muscle twitches. This phase can slightly increase your calorie burn compared to non-REM or light sleep. People who consistently enter and sustain deeper sleep cycles (especially with good sleep hygiene) tend to burn more calories overnight than those with broken or shallow sleep patterns.

That’s another reason quality sleep matters, not just for recovery, but for metabolic efficiency.

Calorie Burn from Sleep Is a Passive Benefit — But Still Real

There’s a misconception that sleep is “doing nothing,” but it’s one of the most metabolically active periods for the brain and body. While you sleep, your body performs cell repair, hormone regulation, memory consolidation, and immune function all of which cost energy. You’re not burning fat at high speed, but you’re supporting the systems that help fat loss work better during the day.

This is why even small improvements in sleep like getting 7.5 hours instead of 5 can lead to noticeable shifts in mood, cravings, and weight control over time.

Cold Environments Can Slightly Boost Sleep Calorie Burn

Your body burns some extra energy to stay warm in cooler conditions. Sleeping in a cooler room (around 17–19°C) can modestly increase overnight calorie burn by activating brown fat, a type of fat that generates heat by burning calories. While this isn’t a game-changer for weight loss, it’s a neat trick that can nudge metabolism upward slightly and promote better sleep quality too.

Sleep Deprivation Slows Metabolism

If you don’t sleep enough, your BMR may decrease, meaning you burn fewer calories across the whole day including while sleeping. At the same time, sleep loss increases ghrelin (hunger hormone) and reduces leptin (satiety hormone), making you feel hungrier and less satisfied with food. The result: you burn fewer calories and are more likely to overeat.

That’s a double hit for fat loss, which is why chronic sleep debt can lead to fat gain, even if your diet doesn’t change much.

Summary

You burn around 280 to 500 calories while sleeping, depending on your weight, metabolism, and sleep duration. While sleep alone won’t make you lose fat, it plays a critical role in maintaining a healthy metabolism, managing hunger, and preserving muscle. For anyone serious about body composition or fat loss, sleep should be viewed as a core pillar of recovery, hormone regulation, and overall energy balance, not just a passive state of rest.