What Would Happen If You Don't Sleep

In 1965, 17-year-old high school student Randy Gardner stayed awake for 264 hours, or 11 days, to see how he would manage without sleep. This groundbreaking experiment aimed to explore the effects of prolonged sleep deprivation on the human body and mind. By the second day, Gardner couldn't focus his eyes, and shortly after, he lost the ability to recognize objects by touch. By the third day, he was irritable and uncoordinated, demonstrating the immediate impacts of sleep loss. As the experiment concluded, he had difficulty concentrating, struggled with short-term memory, became paranoid, and started hallucinating. Remarkably, Gardner recovered without lasting psychological or physical harm. However, others aren't so fortunate; severe sleep deprivation can result in hormonal imbalances, illnesses, and, in extreme cases, death. Although we are just beginning to understand why sleep is necessary, we know it is crucial for overall health and well-being.

Adults need seven to eight hours of sleep each night, while adolescents require about ten. This difference is partly due to the growth and developmental needs of teenagers. We become sleepy due to internal signals indicating fatigue and external cues such as darkness. The increase in sleep-inducing chemicals like adenosine and melatonin leads us into a light sleep that gradually deepens, slowing our breathing and heart rate and relaxing our muscles. This non-REM sleep phase is when DNA is repaired, and our bodies rejuvenate for the next day. In the United States, approximately 30% of adults and 66% of adolescents are consistently sleep-deprived, a statistic that underscores a significant public health issue. Lack of sleep is more than a minor inconvenience; it can seriously harm the body. Insufficient sleep affects learning, memory, mood, and reaction time, and it can also cause inflammation, hallucinations, high blood pressure, and has been linked to diabetes and obesity. These conditions highlight the extensive impact of sleep on various bodily systems.

In 2014, a dedicated soccer fan passed away after staying awake for 48 hours to watch the World Cup. Although his death was due to a stroke, research indicates that consistently sleeping less than six hours a night increases the risk of stroke by 4.5 times compared to those who sleep seven to eight hours regularly. This tragic incident emphasizes the critical need for sufficient sleep to maintain cardiovascular health. For a small number of people with a rare inherited genetic mutation, sleeplessness is a constant issue. This condition, known as Fatal Familial Insomnia (FFI), traps the body in a relentless state of wakefulness, preventing sleep. Over months or years, this condition deteriorates, leading to dementia and death. FFI is an extreme example of how essential sleep is for survival, affecting both mental and physical health in profound ways.

Why does sleep deprivation cause such severe suffering? Scientists believe the answer lies in the accumulation of waste products in the brain. During the day, our cells use energy, creating byproducts like adenosine. As adenosine accumulates, it increases the urge to sleep, known as sleep pressure. Caffeine counteracts this by blocking adenosine receptors, temporarily reducing the feeling of sleepiness. Other waste products also build up in the brain, and if not cleared, they can overwhelm the brain, leading to the negative effects of sleep deprivation such as cognitive impairment and mood disturbances.

So, what happens in our brain during sleep to prevent this? Scientists have discovered the glymphatic system, a cleaning mechanism that removes this buildup and is more active during sleep. This system uses cerebrospinal fluid to flush out toxic byproducts that accumulate between cells. Recently discovered lymphatic vessels in the brain, which serve as pathways for immune cells, might also play a role in clearing out the brain's daily waste. These discoveries have been significant in understanding how sleep restores the brain and maintains its function.

While researchers continue to study the restorative processes of sleep, it's clear that sleep is essential for maintaining our health and sanity. The intricate mechanisms our bodies employ to clear out waste and rejuvenate during sleep highlight its importance. Without adequate sleep, we not only suffer from immediate cognitive and physical impairments but also risk long-term health consequences. Therefore, prioritizing sleep is crucial for sustaining both mental and physical well-being.