Do You Burn Calories During Sleep?

February 15, 2023

Do You Burn Calories During Sleep?

Have you ever questioned if you burn calories while you sleep? And, if so, how many do you burn? While you might think you don't burn too many calories while sleeping, you may be shocked to learn your body is still working at using energy even while you're sleeping.

The number of calories you burn while you sleep depends on a variety of factors, including your metabolism, your weight, and the amount of sleep you're getting each night.

Factors that Affect the Amount of Calories You Burn

Some of these factors include:

  1. Daily Exercise With Strength Training

You can burn more calories, even while asleep just by having more muscle mass. So, this should be an incentive to exercise each day, particularly strength training. However, get your exercise in a few hours before you go to bed if you have difficulty settling down at night.

  1. Your Metabolism Isn't Slowed Down by Eating Late

Eating before you go to bed might cause your metabolism to temporarily increase through what's known as thermogenesis. So, it's not a big deal if you eat something after 8 pm. Doing this won't necessarily make you gain more weight. What does, is the mindless snacking. But, consuming large meals right before you hit the hay could make you feel uncomfortable, and make it more difficult to sleep.

  1. Certain Medical Disorders Might Slow Your Metabolism

Certain medical disorders, like hypothyroidism and Cushing Syndrome, might slow your metabolism, meaning you'll burn less calories at any hour of the day/night, and might even gain or hold onto weight. Your physician can do some simple testing like a blood test for ruling out specific conditions. They'll then work with you to come up with a way of managing your weight and condition.

  1. Body Temperature

Keeping your body cooler can help you burn more calories. When you're wearing thick pajamas, and bundled up in heavy blankets, your body doesn't need to work as hard to supply natural body heat. When you do away with the thick pjs and heavy blanket, and sleep with a cooler body temperature, it makes the thermostat of your body work to provide this natural body heat — and this may help you burn a few more calories during sleep.

  1. Too Little Sleep

When you don't get a minimum of seven hours of sleep a night, it could cause weight gain. When you're not getting at least seven hours of sleep, your hormones responsible for increasing your appetite get working, causing you to eat more than you'd eat if you were well-rested. Along with being hungry, your body also craves carbs, and other high-calorie foods.

Your BMR Has Something to Do With It

Many various factors can influence your metabolism, making it hard to accurately calculate the number of calories you burn while sleeping. However, by estimating your BMR (basal metabolic rate), it's possible for you to come up with a close figure.

It's important your body uses energy continuously for maintenance, and proper functioning. While your body burns some calories during physical activity, your basal metabolism does account for approximately 80% of all your body's energy expenditure.

Your basal metabolism refers to all your body processes that keep it alive, healthy and functioning, including:

  • Blood circulation
  • Breathing
  • Temperature control
  • Nerve and brain function
  • Cellular repair and growth

These metabolic processes need a consistent energy supply; therefore, your body is constantly burning calories, even while you're sleeping or resting.

BMR is the number of calories your body is burning every 24 hours because of basal metabolism. Basically, it's the number of calories you'd use in a day if you didn't perform any physical activity, and only rested.

Various factors affect your BMR, including:

  • Body size
  • Age
  • Genetics
  • Sex
  • Weight and height
  • Muscle-to-fat ratio
  • Hormone levels
  • General health
  • Diet
  • Physical activity levels
  • Medical disorders affecting the metabolism like hyperthyroidism and hypothyroidism
  • Quality and amount of sleep

Because of this, each person's BMR is different. And, you need to take this into account when measuring your own.

BMR is calculated in a fasting state, after eight hours of sleep, and in neutral temperature conditions, so it truly measures the amount of energy your body is using to simply rest.

While you sleep, your body is functioning at around 95% of what it does while resting. So, if you can find the average caloric expenditure for your body while resting (i.e. 45 calories an hour), you can then measure nocturnal calories being burned by this equation: (calories burned or hourly BMR) x .95 (or 95%) x hours asleep.

Your body is constantly working at all hours day/night. While your body is burning calories while you sleep, it's not an ideal strategy for losing weight. Eating well and exercising regularly can help. And, try the best you can to get the suggested seven to nine hours of sleep every night by following good sleep hygiene, and sleeping on a high-quality mattress, like the Eco Terra Hybrid Latex Mattress.

Patrick Gunther

Patrick is an accomplished writer. He has been in the retail mattress space for the past 13 years, and more specifically in the natural mattress niche. He blogs on the subjects of natural mattresses, sleep, health, fitness, and green living.