No Sleep Till Death: How Many Days Will It Take?

Sleep is vital for both physical and emotional well-being. While it is unclear exactly how long a person can survive without sleep, the current world record is 266 hours, or just over 11 days, set by 17-year-old Randy Gardner in 1963. After 72 hours without sleep, deprivation symptoms and fatigue intensify, and an individual's ability to regulate their emotions and accurately perceive the world is severely compromised. While sleep deprivation itself is unlikely to directly cause death, it can increase the risk of dangerous accidents and underlying health issues.

After 24 hours, you may experience impaired coordination and memory

After 24 hours without sleep, you may experience impaired coordination and memory. This is because the brain attempts to conserve energy by entering a state that doctors refer to as "local sleep". During local sleep, the body temporarily shuts down neurons in some regions of the brain but not in others. As a result, your ability to perform complex tasks will significantly decline. You may also experience a decline in your reaction time, as well as impaired judgment and decision-making, diminished memory and attention, impaired vision, hearing and hand-eye coordination, and tremors and muscle tension.

In addition to the physical effects, there are also psychological and emotional consequences of staying awake for 24 hours. You may notice changes in your mood, such as increased crankiness or a shorter temper than usual, as well as difficulty concentrating or making decisions. These symptoms occur due to an increase in stress hormones, such as cortisol and adrenaline, which is your body's attempt to compensate for the fatigue you're experiencing.

The effects of sleep deprivation become more severe with every additional hour you go without sleep. After 36 hours, you may start to experience hallucinations and your health will be more severely impacted. By 48 hours, you will likely be experiencing microsleep, which is when your brain briefly forces you to fall asleep for a few seconds to a few minutes. This can be dangerous if it occurs while driving or in other vulnerable situations. After 72 hours, your ability to regulate your emotions and accurately perceive the world around you will be severely compromised, and you may start to experience more intense hallucinations and delusions.

While it is unclear exactly how long a person can survive without sleep, the current world record is held by Randy Gardner, who stayed awake for 264 to 266 hours (approximately 11 days) as part of a science experiment in 1963/1964. Towards the end of his sleep deprivation experiment, Gardner grew paranoid and started to hallucinate, but he reportedly recovered without any long-term physical or psychological effects. However, he did experience severe insomnia decades later.

After 36 hours, you may begin to hallucinate

After 36 hours without sleep, you may begin to hallucinate. At this point, the effects of sleep deprivation become more severe. You will likely experience increased mood changes, alterations in brain function, and physical symptoms.

The longer you go without sleep, the more intense the side effects become. After 36 hours, you might experience the following:

• Increased sleepiness and fatigue
• Challenges with properly perceiving the length of time
• Reduced concentration
• Reduced ability to think creatively
• Illusions (misidentifying common objects or sounds)
• Simple visual hallucinations, such as seeing something growing from the floor

By this point, your body is under significant stress. Prolonged disruption of your normal sleep-wake cycle increases the production of cortisol, the stress hormone. Hormonal imbalances can affect your body's typical reactions and functions, leading to changes in your mood, appetite, increased stress, and fluctuations in body temperature.

Your body's oxygen intake can also decrease when you stay awake for an extended period. This can lead to further physical and cognitive difficulties.

It is important to note that the effects of sleep deprivation can vary from person to person. However, going without sleep for an extended period is neither safe nor recommended for anyone.

After 48 hours, you may experience microsleep

After 48 hours without sleep, you may experience microsleep. Microsleep is a protective reflex from the brain that forces you to fall asleep for a few seconds. During microsleep, your brain goes "offline" for a brief moment. You may wake up feeling disoriented or you may have no idea that it happened at all.

Microsleep is dangerous, especially if you experience it while driving or in a vulnerable position, as you could unintentionally hurt yourself or others. By this point, you will also be experiencing more intense side effects of sleep deprivation, including increased sleepiness and fatigue, challenges with perceiving the length of time, reduced concentration, and reduced ability to think creatively.

After 48 hours without sleep, you may also experience symptoms of depersonalization and derealization, which are problems with accurately perceiving yourself and reality. You may feel apathetic or euphoric, or have auditory disturbances, such as not being able to recognize where a sound is coming from. You may also feel like you are outside of your body or have difficulty forming thoughts and sentences.

After 72 hours, you may experience symptoms similar to acute psychosis

After 72 hours of sleep deprivation, you will likely experience a range of symptoms, including severe cognitive impairment and perceptual distortions. Your ability to regulate your emotions and accurately perceive the world around you will be severely compromised. You may experience symptoms of psychosis, including hallucinations, delusions, and paranoia.

• Emotional Dysregulation: You may become irritable, anxious, and depressed and struggle with executive functioning and thinking. Your ability to regulate your emotions will be impaired, leading to difficulty controlling your emotional responses.
• Hallucinations and Delusions: You may start to hallucinate, seeing or hearing things that are not there. These hallucinations can be complex and may involve multiple senses. You may also develop delusions, firmly held false beliefs that are not based in reality.
• Perceptual Distortions: Your perception of reality may become severely distorted, and you may struggle to interpret information from your senses accurately. This can include visual distortions, such as changes in the size, shape, or movement of objects, or somatic distortions, such as changes in your sense of body or illusory sensations of movement.
• Cognitive Impairment: Your cognitive functioning will be significantly impaired, impacting your memory, attention, and concentration. You may experience difficulties with decision-making, problem-solving, and performing complex tasks.
• Microsleep: You will likely experience frequent and uncontrollable periods of microsleep, where you briefly lose consciousness for a few seconds without realizing it. This can be dangerous if it occurs during activities that require concentration, such as driving.
• Physiological Changes: Sleep deprivation can also have physiological effects, including increased heart rate, elevated stress hormone levels, and changes in body temperature. Your body's oxygen intake may decrease, and you may experience fluctuations in your appetite and metabolism.

Fatal familial insomnia (FFI) is a rare genetic disease that can cause death via sleep deprivation

Fatal familial insomnia (FFI) is an extremely rare neurodegenerative disease that affects sleep. It is caused by a mutation in the PRNP gene, which results in a malfunction of proteins in the brain. This mutation is inherited, passed down from a parent, although in rare cases, the gene can mutate spontaneously in the egg or sperm that forms the baby.

The PRNP gene is responsible for making the prion protein PrPC, which is located in the thalamus—the region of the brain that regulates sleep. When there is a mutation on the PRNP gene, the amino acids that build the PrPC proteins are not built correctly. This is similar to balling up a t-shirt when you are unsure how to fold it—over time, the drawer becomes difficult to close due to the accumulation of incorrectly folded t-shirts. Similarly, the misfolded proteins collect in the thalamus and become toxic to the cells in the nervous system, creating symptoms.

The symptoms of FFI typically appear when individuals are between the ages of 20 and 70, with an average onset age of 40. The first symptom most people experience is insomnia, or difficulty sleeping, which may be accompanied by confusion and trouble focusing. As the disease progresses, other symptoms may appear, including nervous system overactivity (such as high blood pressure, a faster-than-normal heart rate, and anxiety), hallucinations, and involuntary muscle twitching or jerking (myoclonus).

The disease has four stages. The first stage is characterised by worsening insomnia, resulting in panic attacks, paranoia, and phobias, and lasts for about four months. This is followed by the second stage, where hallucinations and panic attacks become noticeable and continue for about five months. The third stage involves a complete inability to sleep, followed by rapid weight loss, and lasts for about three months. The final stage is dementia, during which the person becomes unresponsive or mute over the course of six months, after which death follows.

While the amount of time a person can survive without sleep is unclear, FFI highlights the importance of sleep for both physical and emotional well-being. Sleep plays a vital role in restoring and maintaining our physical and mental health. When we are asleep, our brain works with our body to support itself, so we feel awake and energised when we wake up. Sleep deprivation can have serious consequences, impacting our ability to think and function normally.

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