Sleep Deprivation: Days Without Sleep And The Impact

Sleep is a vital part of our daily routine, and it doesn't take long for the effects of sleep deprivation to kick in. While the amount of sleep needed varies from person to person, influenced by factors like age and genetics, the consequences of missing out on sleep can be serious and far-reaching. So, how many days can you function without sleep?

After 24 hours without sleep

• Impaired decision-making
• Vision and hearing impairments
• Decreased hand-eye coordination
• Increased muscle tension
• Increased risk of accidents or near misses
• Trouble concentrating
• Problems with cognition and thinking, such as short-term memory loss and brain fog
• Lower performance at work or school
• Increased problems with social cues
• Behavioural issues, especially in children
• Changes in visual perception, such as depth perception and the ability to accurately perceive an object's shape and size
• Increased anxiety or agitation

These symptoms are not usually long-lasting and will typically go away once you've had some sleep. However, it's important to note that the longer you go without sleep, the more severe and intolerable the symptoms become.

After 36 hours without sleep

Extreme Fatigue and Sleepiness

You will have an overwhelming urge to sleep. Microsleeps, which are brief periods of unintentional sleep, may occur. These can happen without you even realising and may last up to 30 seconds.

Cognitive and Brain Function

Your cognitive abilities will be significantly impacted. You may experience:

• Reduced concentration
• Poor decision-making and impaired reasoning
• Problems with creative thinking
• Speech impairments, such as poor word choice and intonation
• Changes in visual perception, such as blurry or double vision

Mood and Emotional Changes

You may experience increased mood changes and difficulty regulating your emotions. This can include feelings of anxiety, agitation, and irritability.

Hallucinations

You may begin to hallucinate and have illusions, such as misidentifying common objects or sounds, or seeing something that isn't there.

Physical Health

The lack of sleep will also affect your physical health. Your sleep-wake cycle helps regulate the release of hormones, including cortisol, insulin, and human growth hormone. As a result, going without sleep for an extended period can alter several bodily functions.

In summary, going without sleep for 36 hours will have intense and far-reaching effects on your body and mind. It is important to prioritise sleep and seek medical advice if you are regularly experiencing sleep deprivation.

After 48 hours without sleep

In addition to the emotional, cognitive, physical, and mental health symptoms that come with prolonged sleep deprivation, you may also experience symptoms of depersonalization and derealization. This means you may have problems with accurately perceiving yourself and reality.

Some other symptoms you may experience after 48 hours without sleep include:

• Switching between feelings of apathy and euphoria
• Auditory disturbances, such as difficulty identifying where a sound is coming from
• Feeling like you are outside of your body
• Difficulty forming thoughts and sentences
• Perceptual distortions
• Increased irritability
• Temporal disorientation

It is important to note that the effects of sleep deprivation can be dangerous and may impair your ability to perform everyday tasks. If you are experiencing sleep deprivation, it is crucial to prioritize getting enough sleep to mitigate the negative consequences on your health.

After 72 hours without sleep

Between microsleep episodes, your ability to perceive the world around you is significantly compromised. Your body and mind will be completely dysfunctional, and you will struggle to interpret your surroundings and read others' emotions. Research involving 12 astronauts who stayed awake for 72 hours found that this stage of sleep deprivation contributes to an increased heart rate, extreme mood swings, and a reduced ability to process information.

Other studies suggest that this amount of sleep deprivation may have more serious consequences, such as circadian misalignment, greater oxidative stress, and neuroinflammation, among others. However, no research has been conducted on humans to prove this.

At this point, your body will be under extreme stress, and you will be at risk of serious health problems. It is important to prioritize sleep to avoid these consequences and maintain your physical and mental health.

Long-term health effects of sleep deprivation

Sleep deprivation can have serious long-term health complications. Over time, sleep disruptions can increase your risk of many different health conditions, such as:

• High blood pressure (hypertension)
• Certain cancers, such as colorectal cancer
• Obesity
• Diabetes
• Cardiovascular disease and hypertension
• Impaired glucose tolerance
• Heart attacks
• Stroke
• Depression
• Increased risk of illness or injury

Frequently asked questions