For those of us either curious about sleep in general or struggling to get consistent sleep, certain questions can come up. One of those questions may include, how long can we survive without sleep?
Here, we’ll break down the timeline of mental and physical repercussions you can expect without any sleep. We’ll also delve into common reasons why people may struggle to get sufficient sleep.
With that in mind, if you are having sleep issues, it’s wise to consult with your healthcare provider or a sleep specialist in order to find out what’s behind your sleep problems and receive proper treatment.
The “No Sleep” Timeline
At 24 Hours
If you’ve pulled an all-nighter studying for an exam or preparing for a presentation at work, you’re going to wish you didn’t procrastinate.
When you’ve gone 24 hours without even a nap, you’re not going to be able to think as clearly. In fact, the National Institute for Occupational Safety and Health reports that this is similar to the effects of having a blood alcohol content of 0.10 percent1, which is above the legal driving limit in the United States at 0.08 percent.
Get More Info: One Hour of Sleep – Is It Enough?
In addition to cognitive impairment2, you can experience the following:
- Poor decision-making3
- Decrease in hand-eye coordination4
- Lower attention span5
- Emotional tendencies5
- Increased risk of death from a fatal accident6
Want to know more? See the latest findings on how one night of poor sleep affects our health.
At 36 Hours
A consecutive stint of 36 waking hours will start to negatively affect your physical health. Repeated exposure to this bad habit can lead to cardiovascular disease7. You may also experience complete memory lapses8 and not remember what happened during these hours.
At 48 Hours
There is limited research on the effects of 48 hours of sleep deprivation. According to a systematic review9 of the available research, the 24-48-hour period of no sleep may lead to symptoms such as distorted perceptions, anxiety, irritability, depersonalization, and disorientation. The review adds that after the 48-hour mark, people may experience complex hallucinations and disordered thinking.
Therefore, it’s possible people may experience a combination of the aforementioned symptoms at 48 hours without sleep.
At 72 Hours
According to the systematic review mentioned above, people can start experiencing delusions after 72 hours without sleep. They add that this can clinically resemble acute psychosis or toxic delirium.9
Have You Gone Without Sleep?
Sleep Deprivation – Possible Causes & Symptoms
Mental Health Issues
Sometimes sleep deprivation may be caused by certain mental health issues10, such as depression, bipolar disorder, schizophrenia, and post-traumatic stress disorder (PTSD). In the case of depression, sleep problems may indicate someone has depression, but sleep loss can also increase the risk of depression.
According to research, people with schizophrenia may simultaneously have a sleep disorder11 such as insomnia, obstructive sleep apnea, restless leg syndrome, or periodic limb movement disorder.
Research experts say sleep disturbances are common among people with bipolar disorder12. They add that people may need less sleep during manic episodes, and during depressive episodes, they may experience insomnia or hypersomnia (excessive daytime sleepiness).
Lastly, the National Center for PTSD13 reports that people with this disorder often say they experience problems with falling asleep, nighttime restlessness, and waking up too early.
Job Schedule
Your job schedule could also lead to sleep deprivation. This can include those who work varying shifts and those who work overnight. When you work different shift schedules, it can throw off your sleep schedule. Similarly, working overnight goes against our natural circadian rhythm14, which prompts us to sleep when it’s nighttime and be awake during the day.
Work or School Deadlines
Sometimes you might stay up late to meet deadlines for work or school, which could lead to sleep deprivation. However, considering that sleep deprivation can impact cognitive performance, this could mean you don’t perform as well the following day.2
If possible, try to adjust your schedule as best you can in order to complete your work earlier so that you don’t have to stay up late. It may also help to talk to your boss or a guidance counselor for advice if your workload is impacting your sleep.
Morvan’s Syndrome
In some cases, sleep deprivation isn’t a choice. No matter how much we want or need to rest, our bodies simply aren’t having it.
A classic example of this is something called Morvan’s syndrome15. Subjects with this medical disorder were studied, and it was found that people with this disorder sleep very little. One particular case involved a man in France16 who went several months with barely a wink. Instead, he had periods of hallucination and pain in his extremities.
Besides pain and sleeplessness, other symptoms of Morvan’s syndrome include muscle twitching, sweating, and weight loss.15
Fatal Familial Insomnia
Fatal familial insomnia (FFI)17 is a fatal form of insomnia that unfortunately does not yet have a cure. The extreme deprivation associated with FFI causes the body to slowly deteriorate18.
FFI is extremely rare, with fewer than 1,000 Americans having the condition. The cause of FFI is genetic and typically the result of a variant in the PRNP gene. Symptoms may begin presenting in adulthood.17
Obstructive Sleep Apnea (OSA)
This sleep disorder occurs when your airway becomes obstructed, creating periodic episodes of reduced or zero airflow19. These low oxygen levels can cause people to wake up multiple times per night, which is why OSA is linked to poor nighttime sleep20 and, subsequently, daytime fatigue.
There are many potential causes of OSA but some common ones may include obesity, physical makeup, sleeping on the back, advanced age, consuming alcohol, or pregnancy.19
If you have this, it can also negatively affect the quality of rest that your partner gets. It’s important to discuss your sleep concerns with your healthcare professional, as OSA has negative health consequences if left untreated.
Restless Legs Syndrome (RLS)
Restless legs syndrome is a nervous system disorder that creates an uncontrollable urge to reposition your legs21. It’s accompanied by uncomfortable tingling and twitching, commonly described as “pins and needles” or a “creepy crawly” feeling. As a result, people with RLS often have worse sleep22.
While this disorder is more common among women, anyone can experience these symptoms, and it’s estimated that it affects up to 10 percent of the population. Additionally, people who are middle-aged or older may present more severe symptoms.21
How Long Can You Go Without Sleep?
There’s no definitive answer as to how long you can stay awake, and based on the effects of sleep deprivation, it’s clear that we require regular sleep to function to the best of our ability.
There is an anecdotal story23 of a young man in China who forced himself to stay awake and died after 11 days, but there were other factors involved. The ethical dilemma involved in testing these boundaries is too great to define a specific timeline, therefore, research in this area is limited. For example, current studies24 have focused on testing in animals such as rats, not in humans.
Frequently Asked Questions
Can you die from lack of sleep?
While not sleeping won’t outright kill you, and death from chronic sleep deprivation is rare, the effects it has on your body can be fatal. In some instances, it could be fatal due to an accident from a lack of sleep.6 We also know that in other cases like Fatal Familial Insomnia, the lack of sleep over an extended period can cause the body to deteriorate.18
How long will it take before you start hallucinating?
While every person is different, research suggests that people may start experiencing hallucinations after 48 hours without sleep.9
Conclusion
It may be tempting to try to trick your body into staying awake. Think about how much more you could accomplish if you slept less, or not at all. Based on the research, though, it’s not advisable to deprive yourself of shut-eye, especially for long periods of time.
Instead, we advise focusing on getting a healthy amount of sleep each night in order to have the energy to accomplish all your tasks in a more timely manner.
Jill Zwarensteyn
Editor
About Author
Jill Zwarensteyn is the Editor for Sleep Advisor and a Certified Sleep Science Coach. She is enthusiastic about providing helpful and engaging information on all things sleep and wellness.
Combination Sleeper
References:
- “NIOSH Training for Nurses on Shift Work and Long Work Hours”. National Institute for Occupational Safety and Health. Last modified March 31, 2020.
- Csipo, Tamas., et al. “Sleep deprivation impairs cognitive performance, alters task-associated cerebral blood flow and decreases cortical neurovascular coupling-related hemodynamic responses”. Scientific Reports. 2021.
- Salfi, Frederico., et al. “Effects of Total and Partial Sleep Deprivation on Reflection Impulsivity and Risk-Taking in Deliberative Decision-Making”. Nature and Science of Sleep. 2020.
- Habibur Rahman Khan, Mohammad., Bin Mohamad, Nasir., Hossain, Salim. “Psychomotor Skills in Total Sleep Deprivation”. International Medical Journal. 2021.
- Pesoli, Matteo., et al. “A night of sleep deprivation alters brain connectivity and affects specific executive functions”. Neurological Sciences. 2021.
- Mahajan, Kirti., Velaga, Nagendra R. “Effects of Partial Sleep Deprivation on Braking Response of Drivers in Hazard Scenarios”. Accident Analysis & Prevention. 2020.
- Huang, Tianyi., Mariani PhD, Sara., Redline MD, Susan. “Sleep Irregularity and Risk of Cardiovascular Events: The Multi-Ethnic Study of Atherosclerosis”. Journal of the American College of Cardiology. 2020.
- McCarthy, Michele E., Waters, William F. “Decreased Attentional Responsivity During Sleep Deprivation: Orienting Response Latency, Amplitude, and Habituation”. Sleep. 1997.
- Waters, Flavie., et al. “Severe Sleep Deprivation Causes Hallucinations and a Gradual Progression Toward Psychosis With Increasing Time Awake”. Frontiers in Psychiatry. 2018.
- “Sleep disorders and mental illness go hand in hand”. University of Texas Southwestern Medical Center. 2017.
- Kaskie, Rachel E., Graziano, Bianca., Ferrarelli, Fabio. “Schizophrenia and sleep disorders: links, risks, and management challenges”. Nature and Science of Sleep. 2017.
- Harvey, Allison G., Talbot, Lisa S., Gershon, Anda. “Sleep Disturbance in Bipolar Disorder Across the Lifespan”. National Library of Medicine. 2009.
- “Sleep Problems and PTSD”. National Center for PTSD. Webpage accessed March 5, 2024.
- Reddy, Sujana., Reddy, Vamsi., Sharma, Sandeep. “Physiology, Circadian Rhythm”. StatPearls. Last modified May 1, 2023.
- Maskery, Mark., et al. “Morvan Syndrome”. The Neurohospitalist. 2016.
- “How Long Can Humans Stay Awake?”. Scientific American. 2002.
- “Fatal familial insomnia”. National Center for Advancing Translational Diseases. Last modified February 2024.
- “Novel Study Model Reveals New Understanding of Fatal Familial Insomnia”. National Institute of Allergies and Infectious Diseases. Last modified January 19, 2023.
- Slowik, Jennifer M., Sankari, Abdulghani., Collen, Jacob F. “Obstructive Sleep Apnea”. StatPearls. Last modified December 11, 2022.
- “Obstructive sleep apnea”. Mayo Clinic. Last modified July 14, 2023.
- “Restless Legs Syndrome”. National Institute of Neurological Disorders and Stroke. Last modified November 28, 2023.
- Massey, T.H., Robertson, N.P. “Restless legs syndrome: causes and consequences”. Journal of Neurology. 2020.
- Dockterman, Eliana. “Euro 2012 Superfan Dies from Sleep Deprivation”. Time Magazine. 2012.
- Vaccaro, Alexandra., et al. “Sleep Loss Can Cause Death through Accumulation of Reactive Oxygen Species in the Gut”. Cell. 2020.