Table of Contents

• Why Do You Burn Calories in Your Sleep? 
• How Many Calories Do You Burn Sleeping?
• How to Understand Your Personal Sleep Metabolism?
• Calculating Your Sleeping Calorie Burn
• Sleep Deprivation and Metabolism
• Tips on Optimizing Sleep to Support Metabolism 
• Wrapping Up

When we think about burning calories, most of us picture intense workouts or cardio sessions. But did you know your body continues to burn calories even while fast asleep? 

That’s right—your body is always working, even when you’re unaware. If so, how many calories do you burn sleeping?

Why Do You Burn Calories in Your Sleep?

While you sleep, your body is far from idle. It performs critical tasks like repairing tissues, consolidating memories, and balancing hormones.

All of this requires energy—which means you’re still burning calories, even in deep rest. 

The number of calories you burn at night depends largely on your basal metabolic rate (BMR)—the amount of energy your body uses at rest to keep basic functions running. This includes keeping your heart beating, lungs breathing, and brain operating smoothly.

How Many Calories Do You Burn Sleeping?

Calorie burn during sleep varies depending on several individual factors, including weight, age, sex, and overall health. Here’s a general breakdown: 

• A person weighing 125 pounds burns approximately 38 calories per hour while sleeping
• Someone at 150 pounds burns about 46 calories per hour
• A person weighing 185 pounds might burn around 56 calories per hour

When you multiply those hourly numbers  by a full night’s sleep (7-9 hours as recommended by sleep experts), the totals are pretty significant: 

Body Weight	Hourly Burn	7 Hours of Sleep	9 Hours of Sleep
125 pounds	38 calories	266 calories	342 calories
150 pounds	46 calories	322 calories	414 calories
185 pounds	56 calories	392 calories	504 calories

That’s roughly the same calorie burn as a 30–45 minute walk—without even leaving your bed! 

How to Understand Your Personal Sleep Metabolism?

The number of calories you burn while sleeping depends on several key factors—many of which are unique to your body and lifestyle. 

Body Composition

Muscle tissue burns more calories at rest than fat tissue. This helps explain why:

• People with higher muscle mass generally have a higher BMR
• Men often burn more calories than women at the same weight due to differences in average muscle mass
• Incorporating weight training into your fitness routine can increase your calorie burn—even while you sleep

Age

As we age, our metabolic rate gradually slows down. A major reason is the natural loss of muscle mass over time. That’s why strength training becomes more important as we get older—it helps maintain a healthier metabolism. 

Sleep Quality and Duration

Not all sleep is created equal. Both the quantity and quality of your sleep play a role in metabolic health: 

• Deep sleep stages (Stage 3 NREM) are especially important for physical repair and metabolic recovery 
• Consistent, high-quality sleep supports hormone balance—including those related to appetite and energy use 
• Chronic sleep deprivation can impair metabolism and may even contribute to weight gain over time 

Calculating Your Sleeping Calorie Burn

If you’re curious about how many calories you burn while sleeping, you can start by calculating your Basal Metabolic Rate (BMR)—the number of calories your body uses in 24 hours at complete rest.

Use the following formulas:

For men: 

66 + (6.2 × weight in pounds) + (12.7 × height in inches) – (6.76 × age in years)

For women: 

655.1 + (4.35 × weight in pounds) + (4.7 × height in inches) – (4.7 × age in years)

Once you’ve calculated your BMR:
Divide that number by 24 (to get your hourly calorie burn), then multiply it by the number of hours you typically sleep.

For example:
If your BMR is 1,500 calories/day and you sleep 8 hours per night:
1,500 ÷ 24 = 62.5 calories/hour → 62.5 × 8 = 500 calories burned during sleep.

Sleep Deprivation and Metabolism

You might be surprised to learn that sleep deprivation can temporarily increase calorie burn. Research has shown that staying awake for 24 hours may boost energy expenditure by approximately 135 calories compared to a normal day with sleep.

However, this doesn’t mean pulling an all-nighter is a smart weight management strategy. In fact, it’s quite the opposite. Chronic sleep deprivation can negatively impact your metabolism in several ways: 

• Raises cortisol levels, which can promote fat storage
• Disrupts hunger hormones like ghrelin and leptin, increasing appetite
• May slow metabolic rate over time
• Impairs decision-making, often leading to poor food choices
• Is associated with a higher risk of obesity and metabolic disorders

Tips on Optimizing Sleep to Support Metabolism

Rather than focusing solely on how many calories you burn while sleeping, look at the bigger picture—how sleep supports your overall metabolic health. 

• Establish a Consistent Sleep Schedule: Going to bed and waking up at the same times daily strengthens your circadian rhythm, supports hormone balance, and improves sleep quality. 
• Create an Optimal Sleep Environment: A cool (around 65°F/18°C), dark, and quiet bedroom promotes deeper, more restorative sleep, which is essential for metabolic recovery. 
• Prioritize Physical Activity: Regular exercise—especially resistance training—boosts muscle mass and raises your BMR, increasing calorie burn even during sleep.
• Be Mindful of Pre-Bedtime Habits: Eating before bed doesn’t automatically slow metabolism. In fact, digestion slightly increases calorie burn (known as the thermic effect of food). However, heavy meals close to bedtime can disrupt sleep. If you’re hungry, opt for a light, protein-rich snack to tide you over. 
• Consider Underlying Health Conditions:  Some medical conditions can affect your metabolism, including hypothyroidism, Cushing’s syndrome, and other hormonal imbalances

If you suspect an underlying issue, consult with a healthcare provider for appropriate evaluation and treatment. 

Wrapping Up

Yes, you burn calories while you sleep—ranging from 266 to over 500 calories per night, depending on your body composition and sleep duration. But sleep’s value goes far beyond calorie burn.

Quality sleep is essential for metabolic function, hormone regulation, physical recovery, and mental clarity.

Instead of viewing sleep as a passive calorie-burning activity, think of it as an active investment in your health. The best approach to long-term metabolic wellness includes: 

• 7-9 hours of quality sleep per night 
• Consistent physical activity, including strength training
• Balanced, nutrient-rich meals
• Effective stress management techniques
• Daily consistency in healthy habits

By focusing on this well-rounded strategy, you’ll support not just your overnight calorie burn, but your 24/7 metabolic health—a true win-win for your body and mind.