How Long Can You Go Without Sleep? The Effects Of Chronic Sleep Deprivation

Medically reviewed by Andrea Brant, LMHC
Updated March 28th, 2025 by BetterHelp Editorial Team

The world record for how long someone went without sleep is 11 days and 25 minutes. This record was set in 1963, but the Guinness Book of World Records eliminated the category in 1997. Why? Because going without sleep for that long is dangerous. 

That said, losing an hour or two of sleep every night can be dangerous, too. Read on to learn more about the health effects of acute and chronic sleep deprivation, the importance of getting enough sleep, and how to get help for sleep-related challenges.

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Sleep and mental health are closely linked

The importance of sleep for mental and physical health and cognitive function

Sleep is essential for physical and mental health. According to the Centers for Disease Control and Prevention (CDC), it can help you stay healthy by supporting your immune system and lowering your risk of chronic conditions, like heart disease, type 2 diabetes, high blood pressure, and stroke. Sleep can also reduce stress, improve metabolism, and help you manage weight. 

Sleep helps your brain work properly, too. When you sleep, your brain forms new pathways to help you learn and remember information. A good night’s sleep can help improve problem-solving skills, attention span, and learning and foster creativity.

How long can you go without sleep?

As mentioned, the longest a human has ever gone without sleep in recorded history is 11 days and 25 minutes. Many of us have also pulled “all-nighters” before, perhaps even staying up for 24 hours straight a time or two. Not sleeping for this long every once in a while may not have long-term consequences, but it can affect you in the short-term. 

Staying awake for 24 hours can be comparable to having a blood alcohol level of 0.1%, which is above the legal limit and can make you feel and act like you’ve been drinking. You might experience slurred speech, slow reaction times, and impaired hand-eye coordination. You will also experience an influx of stress hormones as your body attempts to compensate for the fatigue.

After 36 hours, not sleeping can begin to impact your health significantly. Staying awake for this long puts a lot of stress on the body, causing inflammation, hormone imbalances, and slowed metabolism. By the time you’re awake for 48 hours, your brain forces you to fall asleep for up to 30 seconds at a time. These periods of microsleep are a protective mechanism, but they can also be dangerous—particularly if you’re driving or engaged in other activities where you could hurt yourself or others.

For every additional hour you stay awake, all of these symptoms intensify. There’s currently not a lot of research for what happens when you stay awake for 72 hours at a time, as most people can’t stay awake this long on their own, and forcing them to do so for research purposes is unethical. At this point, a person may not accurately interpret the world around them. They are likely to struggle with executive function and controlling their emotions and may even experience hallucinations.

Acute vs. chronic sleep deprivation

There are two types of sleep deprivation based on how long a person hasn’t been getting enough sleep:

  • Acute sleep deprivation refers to no sleep or a reduction in sleep for a short period of time—usually a day or two. Acute sleep deprivation can result from anything that impacts sleep quality or quantity for a night or two, including shift work, travel, stress, or environmental factors. 
  • Chronic sleep deprivation can occur when a person routinely sleeps less than what is needed for optimal functioning. Most adults need seven to nine hours of sleep a night; consistently getting less than this can lead to ongoing health challenges. 

Side effects of sleep deprivation

Acute sleep deprivation may lead to short-term mental and physical health challenges. Chronic sleep deprivation can have longer-lasting effects. 

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Possible physical health side effects

Sleep loss can have multiple long-term impacts on physical health, and sleep loss doesn’t have to be extreme for a person to feel these effects. In fact, consistently sleeping less than seven hours a night is enough deprivation to have wide-ranging physical effects on the body, including increased risk of: 

  • Obesity. One older study that followed participants for 13 years suggests that, by age 27, those who regularly slept less than six hours a night were 7.5 times more likely to have a higher body mass index (BMI). Obesity can increase the likelihood of developing obstructive sleep apnea, which can further disrupt sleep quantity and quality.
  • Diabetes. Studies have also indicated that sleep loss may increase the risk of diabetes. For instance, one meta-analysis suggests that sleep disorders are highly prevalent in people with type 2 diabetes, with 52% of people with diabetes also having a sleep disorder. Unspecified sleep apnea was the most common, followed by obstructive sleep apnea and restless leg syndrome.
  • Heart disease. Not getting enough sleep can trigger hormonal and physiological changes that can cause inflammation and increase the risk of heart disease. Research suggests that sleeping less than six hours a night may increase the risk of heart attack by 20%.

Effects on cognitive function

Severe sleep deprivation can also contribute to cognitive impairment. It can impact judgment and decision making, disrupt memory consolidation, and decrease attention and alertness. These effects may also contribute to risk-taking behavior and slower reaction times, making accidents more likely.

Mental health side effects

Sleep deprivation can also lead to mental health symptoms. Some research suggests that people with insomnia may be 10 times more likely to experience depression and 17 times more likely to experience anxiety. There is also evidence to suggest that sleep problems may be associated with other mental health challenges too, including post-traumatic stress disorder, eating disorder, delusions, and hallucinations.

What causes sleep deprivation?

Multiple factors can contribute to sleep loss. One is age. As we get older, we tend to spend less time in deep sleep, waking an average of three to four times a night. Environmental and lifestyle factors can play a part, too. Examples include working longer hours, working evening and overnight shifts, or traveling between different time zones frequently. Other factors that may contribute to acute sleep deprivation or more prolonged sleep deprivation include anxiety, depression, insomnia, chronic pain, and substance use. Sleep loss can be seen as a symptom; one often has to identify the underlying cause to manage it.

If you are struggling with substance use, contact the SAMHSA National Helpline at 1-800-662-HELP (4357) to receive support and resources. Support is available 24/7.

How to manage sleep deprivation

Managing sleep deprivation can depend on the underlying cause, but treatment often focuses on changing how one sleeps or addressing what is disrupting one’s ability to sleep. 

Some people can get more rest or better-quality rest by adjusting their pre-sleep routine. Going to bed at the same time every night and waking up at the same time every day—even on the weekends—can be beneficial. Aim for a bedtime that allows for at least seven to eight hours of sleep, and consider doing something relaxing before heading to bed, like taking a warm bath or listening to soothing, relaxing music or an audiobook. 

Getting active during the day may also help improve sleep quality, even if you just go for a walk. You might try avoiding using screens, drinking alcohol, and eating heavy meals in the hours leading up to bedtime as well.

Can you completely recover from the effects of sleep deprivation?

Getting enough quality sleep may help you recover from even long-term sleep deprivation. However, it can take days or even weeks to recover completely, and any health challenges that may have developed in the meantime may not resolve with more sleep alone.

When to see a doctor

Many people are able to manage being sleep-deprived on their own, but if you are experiencing extreme sleep deprivation and attempts to increase how much sleep you’re getting are ineffective, it can be beneficial to talk to your doctor. You may be experiencing a sleep disorder that requires medical intervention.

How long can you go without sleep treatment?

If you’re experiencing chronic lack of sleep and/or signs of a sleep disorder, seeking treatment as soon as possible can be paramount. Even one day of sleep deprivation can result in the short-term effects cited above, such as increased risk of accidents. That’s why paying attention to your sleep habits and seeking help as soon as you notice a potential problem can be advisable.

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Sleep and mental health are closely linked

Getting mental health support for sleep problems

If you’re experiencing mental health impacts from a lack of sleep or if you have underlying mental health challenges that are affecting your sleep, working with a therapist may be helpful in addition to seeking medical care. The American College of Physicians recommends cognitive behavioral therapy for insomnia (CBT-I) to treat insomnia and related challenges. This type of CBT includes both cognitive and behavior-based interventions as well as education on sleep hygiene. 

Sleep deprivation can significantly impact many areas of health, some of which may make it dangerous to drive to an in-person therapy session. In such cases, online therapy can be a safer, more convenient option for receiving care. With an online therapy platform like BetterHelp, you can get matched and then meet with a licensed professional remotely from the comfort of home. Many people can be matched with a provider in as little as 48 hours of signing up, so you can typically get started soon. 

Research indicates that online treatment may often be an effective option for addressing sleep problems. For instance, one study suggests that internet-delivered CBT-I “produced statistically significant pre- to post- reductions in symptoms of insomnia” and helped improve symptoms of depression, anxiety, and functional impairment related to insomnia.

Takeaway

The longest anyone has ever gone without sleep is a little over 11 days, but this is highly dangerous. Even staying awake for 24 hours can impact your mental health and cognitive abilities. Many people may not realize that sleep deprivation can also occur from insufficient high-quality sleep, and that even a few nights of getting less than six hours can significantly affect your health. If you’re experiencing mental health effects of inadequate sleep or if you have underlying mental health conditions that are impacting your sleep, meeting with a doctor and a therapist may help.
Learn the impacts of sleep deprivation
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