Can lack of sleep actually kill you?

Joanna Sosnowska 6 minutes read

“What if I sleep less?” Whether we ask ourselves this question or not, it seems that we all should know the answer beyond “Then, I’ll have more time to do fun stuff at night!” We should know it because stealing time away from your sleep to squeeze more into your evenings and nights has become a norm, rather than an occasional indulgence. The culture of “Work hard, play hard” and “I’ll sleep when I’m dead” relegated the nightly rest to an unnecessary nuisance enjoyed by the weak and boring.

But, the times, they are a-changing – to borrow from a recent Nobel Prize winner, and it’s no longer that cool to completely disregard your organism for the sake of a career or a good time and be blissfully oblivious to the often drastic consequences. As it turns out, good sleep hygiene (about which you can read here) is an essential element of your well-being. But, if you decide to cut back on sleep or, on some nights, skip it completely, it’s not a bad idea to understand what you’re doing to your body before you make that call.

Couple hours

An infrequent episode of shortened sleep should not be anything to worry about, but what happens when it becomes more of a norm? If you regularly sleep less than 6 hours, then that puts you in the “sleep deprived” category. Surprised? Sadly, in this situation, no system in your body remains unaffected.

The first thing affected by the sleep deficit is your nervous system. Your brain doesn’t perform to its full capacity which seriously impairs your cognitive abilities, lowering the quality of your mental faculties. So, those two or three extra hours of work or study at night may not be worth it – you’re simply not going to get that much done. Mood swings and overall irritability are also common effects, as emotional health is likely to deteriorate too. In more serious cases, it might even lead to depression or paranoia.

One night

Let’s say you miss an entire night of sleep. Cramming for an exam, a newborn baby or an unfinished quarterly report will do that to a person. How does that affect your body? First of all, your brain’s reaction will be to release more dopamine. Dopamine is, generally speaking, a ‘feel-good’ hormone, so the first perceived effects of no sleep may actually not be that bad. You may feel extra motivated, get a little energy boost and your sex drive could go up. Sadly, it is all very short-lived. After a few hours, you’ll eventually start feeling run-down and sleepy, and your planning and decision-making skills will significantly deteriorate, making you more impulsive. Driving after a sleepless night is definitely not a good idea, since your reaction time is significantly slower. In fact, it can be compared to that of a person with a blood alcohol content of 0.08, so you’re legally drunk.

Two nights or more

Going without sleep for more than one day obviously deepens the adverse effects. Your metabolism will gradually slow down to a point where your body is no longer able to break down any glucose. On the other hand, your appetite will go up, causing you to overeat. Your immune system will also temporarily shut down, making your body much more prone to any illnesses and infections. Since your body produces much more cortisol, any wrinkles or fine lines will become much more apparent. At this point, your sex drive will also become pretty much nonexistent.

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After three days you might start experiencing minor hallucinations and memory lapses. Extreme sleep deprivation for extended periods, can also cause micro sleep. This means falling asleep for a few seconds or even minutes without realizing it. That’s why performing some jobs or driving a car in such state carries a very serious safety risk for you and others around.

Read also: 10 must-know things if you don’t sleep well

General sleep deprivation

As mentioned before, sleep deprivation makes it much easier to get sick. It’s your immune system reacting to the lack of rest. Being asleep allows your body to produce antibodies and cells responsible for protecting you from diseases. Your respiratory system also suffers as a result because it becomes much more vulnerable to infections and worsening of any chronic lung diseases such as asthma.

Getting enough sleep is vital to keeping a healthy weight as well. Sleep deprivation is a risk factor for obesity that is just as serious as overeating or lack of exercise. It makes your metabolism much slower and generates higher levels of insulin in the body. Controlling your appetite becomes much harder, as the chemicals responsible for appetite control and stimulation are destabilized. As bad as it sounds, fat storage is not the biggest threat here. Actually, it is the type 2 diabetes that you should really be afraid of, since not sleeping enough makes you even up to 2.5 times more likely to develop it.

Some of the other effects of sleep deprivation include heart palpitations and higher blood pressure.

A vicious cycle of sleeplessness

As with most sleep-related problems, the effects of sleep deprivation create a kind of vicious cycle of sleeplessness. Besides causing many problems described above, lack of sleep can actually worsen the problem with sleep itself. For example, depression (which can be an effect of not sleeping enough) can cause insomnia, a sleep disorder involving trouble with sleeping and falling asleep. Similarly, lack of sleep stimulates the production of cortisol which is a hormone that boosts stress which might also keep you up at night. Obesity is a risk factor for sleep apnea, and so on and so forth.

Moreover, the judgment of sleep-deprived people is generally much more clouded, especially when it comes to actually assessing if they get enough rest. They may start believing that they’ve adapted to the shortened sleep and that it’s enough for them. While your organism is generally good at telling you what you need, sleep deprivation causes you to lose touch with that voice.

Sleep on your decision to cut sleep

The jury is in and the verdict couldn’t be clearer. Depriving yourself of sleep, though sometimes unavoidable, is seriously detrimental to your well-being and long-term health. It has been assessed that sleeping less than 6 hours a night for a prolonged period of time corresponds to a 12 percent higher chance of premature death. Think about this stat the next time it’s 11 pm and you’re thinking of putting on another episode of your favorite series.

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Nightly is a multidisciplinary team of sleep scientists, psychologists, engineers and experts in the fields of neuroaesthetics and cognitive film theory who have dedicated themselves to developing a safe sleep aid for those dealing with sleep disorders. After over 3 years of studies and research, the Nightly app launches in the fall of 2017. It is the first complete sleep assistant featuring Sleep Stimulation technology which actively maintains a calming sleep environment to help you enjoy peaceful nights of restful sleep. The app uses the science of audio-visual stimulation to assist you in making the most of your nightly rest from the moment you go to bed to the time you wake up. Find out more about how it works here.


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Reclaim your night and start your day full of energy. Sleep with Nightly tonight