Sleepless Nights: Is It Really That Uncommon?

Sleep is vital for both physical and mental health, and going without it for extended periods can have serious consequences. While it may seem like a good idea to put off sleep to get more done, the unpleasant side effects of sleep deprivation will eventually catch up with you. So, is it normal to not sleep for two days?

After 24 hours without sleep

According to the Centres for Disease Control (CDC), being awake for 24 hours is similar to having a blood alcohol concentration of 0.10%, which is over the legal limit for driving in the US. As such, you are likely to experience reduced reaction time, impaired judgement and decision-making, diminished memory and attention, impaired vision, hearing and hand-eye coordination, and tremors and muscle tension. Your body will also increase its production of stress hormones like cortisol and adrenaline in an attempt to compensate for the fatigue you are experiencing.

While missing 24 hours of sleep won't cause major health problems, the longer you stay awake, the more severe and less tolerable your symptoms will become.

After 36 hours without sleep

Sleep is vital for health, and experts recommend that adults get at least seven hours of sleep per day. After 36 hours without sleep, you will likely experience a range of symptoms, including:

• Increased mood changes and difficulty regulating emotions
• Alterations in brain function, including reduced concentration and a reduced ability to think creatively
• Physical symptoms, such as increased sleepiness and fatigue
• Challenges with properly perceiving the length of time
• Illusions, such as misidentifying common objects or sounds
• Simple visual hallucinations, such as seeing something that isn't there, like something growing from the floor

The longer you go without sleep, the more severe the symptoms become. By 48 hours without sleep, you are likely to experience symptoms of depersonalisation and derealisation, which are problems with accurately perceiving yourself and reality.

After 48 hours without sleep

Microsleep can be dangerous, as you could unintentionally hurt yourself or others. For example, if you were to nod off while driving, cooking, or operating heavy machinery, it could be fatal.

After 48 hours, your body will also be under a lot of stress. Your stress hormones will be high, and your immune system will be weakened. Your ability to regulate your emotions will be compromised, and you may feel irritable, anxious, or depressed. Your cognitive performance will be impaired, and you will be very fatigued.

You may also experience blurry or double vision, which could lead to distortions of reality and hallucinations. These hallucinations can incorporate multiple senses and may become harder to distinguish from reality.

Additionally, you may experience depersonalisation, feeling like you are outside your own body and mind. As a result, you may seem unemotional or careless to others.

After 72 hours without sleep

Staying awake for two days (48 hours) is classed as extreme sleep deprivation. At this point, the brain will start entering brief periods of complete unconsciousness, known as microsleep. This occurs involuntarily and can last for several seconds.

In a 2015 study, two astronauts experienced impaired cognitive functioning, increased heart rate, and a reduction in positive emotions after staying awake for 72 hours.

Some effects of staying awake for 72 hours include:

• Difficulty multitasking
• Severe concentration and memory issues
• Difficulty communicating with others
• Slurred speech
• Unsteady walking
• Complex hallucinations
• Irritability
• Anxiety
• Depression
• Struggles with executive functioning and thinking
• Illusions

It can take days or weeks to recover from sleep deprivation. The longer a person has been awake, the longer it will take to get back on track.

Short-term vs. chronic sleep deprivation

Sleep deprivation can occur after just 24 hours of no sleep. However, the longer you spend awake, the more severe and less tolerable the symptoms become. After 48 hours of no sleep, you will experience extreme sleep deprivation, with an overwhelming urge to sleep, an increased appetite, extreme fatigue, and microsleeps. After 72 hours, your urge to sleep will strengthen and possibly become uncontrollable, and your hallucinations might become more complex. After 96 hours, your perception of reality may be severely distorted, resembling acute psychosis.

Short-term sleep deprivation can cause impaired coordination and memory, raised levels of stress hormones, increased blood sugar levels, and a higher risk of accidents. It can also negatively impact your overall performance and has been linked to major fatal accidents.

Chronic sleep deprivation, on the other hand, is associated with a variety of long-term health problems, including mood and mental health changes, diabetes, kidney disease, stroke, and heart disease. It can also increase the risk of obesity and metabolic syndrome. Additionally, it can lead to high anxiety, irritability, erratic behaviour, poor cognitive functioning, and performance, and psychotic episodes. Chronic sleep deprivation can also have significant long-term effects on children, including poor academic performance, problems getting along with others, a higher risk of engaging in dangerous and antisocial behaviours, and problems with physical growth and development.

To summarise, while short-term sleep deprivation can cause a range of issues, chronic sleep deprivation tends to have more severe and long-lasting consequences, affecting various aspects of an individual's health and well-being.

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