Can sleep deprivation kill - is it really worth going to bed later?

11 days and 24 minutes - that's the longest documented period without sleep. So far, no one has beaten the record held by Randy Gardner, although many unconsciously try to by notoriously giving up their night's rest. Statistics confirm this: while at the beginning of the 20th century we slept on average 9 hours, nowadays only 6. Althoughsleep deprivation doesn't kill, its short and long-term effects on mental and physical health can be disastrous.

Short-term effects of sleep deprivation

The first sleepless night - a false sense of euphoria

Work to be done the day before yesterday, a stressful exam the next day, a child who loudly articulates its needs in the middle of the night. And also this permanent shortage of time, because the day does not want to stretch. To cope with all the responsibilities, we give up sleep.

The first sleepless night will probably convince us that this is an excellent idea. This is when neurons in the central nervous system synthesize and release larger amounts of dopamine, a neurotransmitter not coincidentally called the "happy hormone." We owe to it a feeling of well-being, a surge of energy, and even a sense of euphoria - the same that accompanies the initial states of falling in love.

Unfortunately, this bliss does not last long - after just a few hours, fatigue and sleepiness sets in. And after 36 hours without sleep, the ability to plan and coordinate work begins to fail. We become less attentive and more susceptible to distractions. Reaction time also decreases significantly. People deprived of sleep for one night and people with 0.08 per mille of alcohol in their blood will react at a comparable rate.

Risks of lack of sleep: obesity, lowered immunity, memory problems

A second sleepless night brings only negative effects. Metabolism slows down rapidly. Just one night od sleep deprivation means that the metabolism slows down by 5-20 percent. To make matters worse, the appetite for high-calorie products increases and people who don't get enough sleep tend to eat more. They also more often decide to eat unhealthy, highly processed food. This leads to overweight and obesity, as confirmed by research conducted by Dr. Kristen Kntuson from the University of Chicago. They show that sleeping less than 6 hours leads to increased BMI (Body Mass Index). Insufficient sleep disturbs the secretion of the hormones ghrelin and leptin, and this disturbs the feeling of satiety and increases appetite.

As a result of sleepless nights, the immune system also suffers - it is not able to defend itself against microorganisms effectively. According to Matt Walker, a sleep researcher at the University of California, Berkeley, 4-hour sleep results in a weakening of the body by up to 70 percent. No wonder people who sleep short get colds three times more often than those who sleep the "prescribed" 8 hours.

Sleep is also good for successful sex life. When it's too short, testosterone secretion decreases, which in both men and women affects sexual desire. According to a study published in the Journal of Sexual Medicine, it only takes a little to get back in shape. Researchers studied 171 women who rarely and reluctantly had sex due to fatigue and sleep deprivation. Each hour of extra sleep increased their sexual activity by 14 percent.

Lack of sleep also adversely affects your appearance. And it's not just bags under the eyes; fine lines and wrinkles become more visible over time. This is due to the increased secretion of cortisol, the stress hormone, which destroys the collagen fibers that provide skin elasticity and stretch.

After 3 sleepless nights, you may already experience hallucinations and even memory loss. In this state, performing certain jobs or driving a car becomes dangerous - to yourself and those around you.

Long-term effects of sleep deprivation

Lack of sleep equals ineffective learning?

Sleep that typically lasts less than 6 hours (which is the current global average), from which nightmares regularly awaken - this is a description more than likely indicative of sleep deprivation. In the long term, its consequences can be disastrous for physical and mental health.

Cognitive functions are disturbed, there are problems with concentration, difficulties in recognizing changes in the environment, memory failures. Therefore, the productivity of a person who spent an extra 2-3 hours studying at the expense of sleep seems highly questionable.

Anyway, already in 1924, it was discovered that people who sleep longer remember more. And they have a more stable mood because sleep deficiency is usually accompanied by emotional instability, irritability, and even aggression.

Insomnia: cause of depression?

Insomnia is one of the symptoms of depression, but it can also be a causal factor. The risk of developing depression in patients with insomnia is four times higher than in healthy people. They are also more likely to suffer from anxiety disorders and struggle with alcohol problems. It's a vicious cycle - lack of sleep stimulates the secretion of cortisol, the stress hormone, putting the body into a state of readiness and wakefulness. And again, we can't fall asleep, so its production increases, and so on.

People who suffer from sleep disorders take more often uncontrollable naps during the day - a few seconds or a few minutes, which are not even registered by the consciousness. As sleep researchers Giulio Tononi and Chiara Cirelli of the University of Wisconsin-Madison argue in Scientific American, naps are the body's defense mechanism. During naps, the brain repairs connections between nerve cells and organizes stored information. However, taking naps during the day while regularly not getting enough sleep is a short-term, ineffective and harmful solution.

An experiment conducted by Prof. Sigrid Veasey from the University of Pennsylvania showed that mice, after three sleepless nights lost up to 25% of cells in a region of the brain stem called the reticular formation. It is responsible for maintaining a state of consciousness and wakefulness and returning to reality after waking from a deep sleep.

Can lack of sleep kill?

After 11 days of sleep deprivation, Randy Gardner asserted that he felt remarkably well. The scientists under whose care he had been during the experiment claimed that he behaved normally and that his statements were sensible and logical. When asked to perform a simple calculation-subtracting from 100 consecutive sevens-he suddenly stopped at the number 65. When asked why he admitted with disarming honesty that he had forgotten what he was supposed to do.

For ethical reasons, a similar experiment has not been repeated. At least in laboratory conditions, because at home, we willingly sacrifice sleep for other activities. We risk a lot - it has been proven that sleeping less than 6 hours increases the probability of premature death by 12 percent in the long run. Is it really worth going to bed later?

Interested in similar topics? You may also be interested in this article: Nightmares are more common in people who sleep longer