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Can Sleep Deprivation Cause Weight Loss?

by Dale Cudmore | Updated: Jan 14, 2022

Some studies show that sleep deprivation may cause weight loss in certain situations, but most research suggests that sleep deprivation over the long term typically causes weight gain.

Common sense tells us that a large portion of the population are overweight and also sleep deprived, so it’s clearly not some secret technique for weight loss.

It’s a fairly complex subject, and while there is some research on sleep restriction and weight loss, there’s still a lot we don’t know.

I’ll summarize the best studies on this subject at the moment in this short post.

Studies Showing Sleep Deprivation Causing Weight LOSS

The fact that there aren’t too many studies that show that sleep deprivation might trigger weight loss demonstrates that even if a lack of sleep may increase weight loss, it only has a limited effect, and only under certain conditions.

Every long-term study on people who are sleep deprived find universally negative consequences.

An animal study found that sleep deprived rats did show weight loss (1). Obviously you can’t take too much away from that.

Researchers proposed that having more time awake led to burning more calories, and therefore weight loss.

Another study in humans also found that sleep deprivation increases energy expenditure and decreases energy conservation in the short term (2).

However, they make a great point in the summary:

The finding that sleep deprivation increases energy expenditure should not be interpreted that sleep deprivation is a safe or effective strategy for weight loss as other studies have shown that chronic sleep deprivation is associated with impaired cognition and weight gain.

If someone actually wants to lose weight, they should focus on eating a healthy calorie-restricted diet and getting enough sleep (not less).

SummarySleep deprivation may increase energy consumption in the short term, which can lead to accelerated weight loss in some people. However, long-term sleep restriction is almost always harmful.

Research Showing Sleep Deprivation and Weight GAIN

There’s a link between sleep problems and obesity, and even conditions like diabetes.

One research team proposed that sleeping less could actually lead to weight gain and increased insulin resistance through 3 main mechanisms (3):

  • Altered glucose metabolism - Sleep restriction can impact how the body digests and uses stored sugar.
  • Increased appetite - Sleep restriction has been shown to increase appetite. That alone can lead to eating more, but the fact that sleeping less means there is more time to eat can also play a role.
  • Lower activity levels - In the short term, energy expenditure increases. However, being sleep deprived habitually means you’re tired all the time and are more likely to exercise less.

The most interesting part of that paper is the summary of the effect of sleep restriction on hormone levels and appetite:

After 2 days of reducing sleep from 10 hours to 4 hours, subjects had a much higher appetite (23%), which is correlated with the increase in the “hunger” hormone ghrelin.

In addition, appetite for high carbohydrate foods (e.g. unhealthy foods like bread and cake) was even higher.

SummaryIn most cases, sleep restriction leads to an increase in appetite, which can lead to weight gain if people overeat because of it. Most importantly, people start to crave unhealthy foods, which will have other side effects that make weight gain more likely.

Sleep Restriction May Cause the Wrong Type of Weight Loss

Most people consider weight loss as a good thing, because most people are overweight these days.

However, losing a pound of muscle is not the same as losing a pound of fat. Lean tissue is generally considered a good thing, while fat is not.

Research suggests that weight loss while sleep deprived will result in more lean tissue being lost than if someone had adequate sleep.

One study split overweight subjects into a control and experimental group while on a calorie restricted diet. In the experimental group, subjects had just an hour of sleep restriction added on 5 nights a week for the study (4).

The findings were as follows:

The control and experimental groups lost similar amounts of weight, lean mass, and fat mass. However, the proportion of total mass lost as fat was significantly greater in the control group.

In other words, even though both groups lost the same amount of weight overall, the small amount of sleep deprivation led to less fat loss and more lean tissue loss.

Another study that reached a similar conclusion proposed that the reduced sleep may cause this by (5):

  • Increasing ghrelin (hunger hormone)
  • Decreasing leptin (important for burning fat for energy)
  • Increased wakefulness (may burn more energy, but also provides opportunities to eat more)

SummarySleep deprivation did not help or hinder weight loss in these studies. However, sleep restriction did lead to losing less fat and losing more of desirable mass like muscle.

Other Effects of Sleep Deprivation That Could Affect Weight

Almost everyone undervalues the importance of sleep.

Weight is certainly an important consequence of poor sleep, but there are other side effects as well that can affect one’s health:

Sleep is essential for good health in so many ways, so even if sleep restriction could help with short-term weight loss slightly, the risks don’t outweigh the benefits.


  1. A Reassessment of the Hyperphagia/Weight-Loss Paradox During Sleep Deprivation
  2. Energy expenditure during sleep, sleep deprivation and sleep following sleep deprivation in adult humans
  3. The metabolic consequences of sleep deprivation
  4. Influence of sleep restriction on weight loss outcomes associated with caloric restriction
  5. Partial Sleep Deprivation and Energy Balance in Adults

Medical Disclaimer: The information on is not intended to be a substitute for physician or other qualified care. We simply aim to inform people struggling with sleep issues about the nature of their condition and/or prescribed treatment.

About the authorDale is the founder of Snooze University and a sleep researcher. I overcame my sleep issues and now I'd like to help you do the same by summarizing the latest sleep studies for you.