How does most of us feel after a sleepless night? Tired, irritable and, as if, “out of place.” But a night’s sleep lasting less than the recommended 7-9 hours makes a person not just distracted and nervous. The consequences of chronic sleep deprivation are much more serious and can cause a variety of health problems: from weight gain to a weakened immune system.
Why should we sleep
The human body needs sleep just as much as it needs air or food. During sleep, many processes occur in our bodies, on which the chemical and hormonal balance, the adequacy of the functioning of the brain and other vital organs depend. The results of 16 scientific studies conducted by experts from around the world have confirmed that if you sleep less than 6 hours a day, the risk of early death increases by 12%. Long-term sleep deprivation can cause more serious harm than just making a person tired. Quality sleep is necessary in order to stay healthy. This is the time when the recovery processes are most active in the body.
At first glance, it may seem that when we sleep, all the systems in our bodies also rest. In fact, at this time, many processes occur in the body, which determine what a person will be like after awakening. Shortly after falling asleep, in the slow sleep phase, the human body resembles a biochemical plant: it actively produces antioxidants, growth hormone, melatonin, testosterone, dehydroepiandrosterone. All these substances are necessary for restoring chemical balance, the formation of cells and tissues, strengthening bones, muscles, and the immune system. As soon as sleep goes into a fast phase, the brain takes over the work: it processes and stores the information received during the day (it is during this period that everything learned is memorized). The last sleep cycle (in the morning) plays a crucial role in improving a person’s mood and creative abilities.
How to understand that the body lacks rest
If a person often yawns, complains of drowsiness, feels tired and irritable during the day, this can be regarded as signals from the body about sleep deprivation. Many people struggle with this condition with the help of caffeine. Nevertheless, even if you eliminate the signs of drowsiness with the help of stimulants, this does not mean that the dangerous processes occurring in the body due to sleep deprivation have stopped.
How sleep deprivation affects different systems
To understand what causes sleep deprivation and whether it is possible to die from chronic sleep deprivation, it is necessary to understand what processes in this case occur in different body systems.
Central nervous system
The central nervous system can be compared to the main highway through which all the most important information for the body is transmitted. For this system to function properly, a person needs proper rest. Against the background of chronic sleep deprivation, the information transmission scheme along this highway is disrupted.
While a person is sleeping, special connections are formed in his brain between nerve cells (neurons) that help to remember new information. Due to sleep deprivation, the brain is deprived of the ability to adequately perform this function. Therefore, it is more difficult for people suffering from insomnia to concentrate, remember new things and recall what they learned earlier.
Sleep deprivation negatively affects a person’s mental abilities and psycho-emotional state. After a sleepless night, most of us become irritable and more prone to sudden mood swings. Sleep deprivation also affects the ability to make adequate decisions and show creativity. In addition, coordination may be disrupted after a sleepless night. And this is also a consequence of the fact that a tired brain sends the wrong impulses to the body.
If insomnia is chronic, a person may have hallucinations (visual and /or auditory), signs of manic depression or other mental disorders. Chronic sleep deprivation makes a person prone to paranoia, depression, impulsive behavior, and also pushes to thoughts of suicide.
By the way, if the central nervous system does not get the necessary rest at night, then during the day a person may fall asleep (often he does not even notice it himself). Sometimes this state can last for seconds, sometimes for minutes. The danger of such failures is that a person is not able to control them, and “blackouts” can happen while driving a car or doing other work that requires increased attention. And this is a serious risk to life.
While a person is sleeping, his immune system is working intensively. It is during sleep that the immune system actively produces cytokines – substances that help the body resist bacteria and viruses. In addition, during sleep, the body accumulates the strength necessary to protect against diseases.
Sleep deprivation does not allow the immune system to build up energy. That is, if the body lacks rest, it weakens and becomes easier prey for pathogenic viruses and bacteria. Against the background of chronic sleep deprivation, the body will need much more time to recover from the disease than those people who follow a healthy rest regime. If sleep deprivation is chronic and has been going on for quite a long time, this significantly increases the risk of developing cardiac diseases and diabetes mellitus.
As for the respiratory system and the quality of sleep, there is a mutual relationship. On the one hand, a respiratory disorder in the form of obstructive apnea (night snoring) can interrupt sleep and reduce the quality of rest. But if you look at the problem from the other side, it becomes obvious that sleep deprivation reduces immunity and makes a person more vulnerable to respiratory infections. And those, in turn, can cause complications in the form of diseases of the respiratory system, accompanied by a strong cough, nasal congestion and snoring, which in turn cause frequent awakenings at night.
The quality of a night’s sleep largely depends on the health of the heart and blood vessels, including pulse and blood pressure. Sleep is indispensable when it comes to restoring the body after cardiac diseases. European scientists have found evidence that insomnia increases the risk of heart attack and stroke.
The endocrine system
There is an obvious relationship between the functioning of the endocrine system and the duration of sleep. For example, the body needs at least 3 hours of uninterrupted sleep to produce testosterone. Waking up in the middle of the night can disrupt the production of this hormone and, as a result, cause an imbalance of the overall hormonal background. Frequent awakenings at night can also affect the production of growth hormone. For this reason, sleep deprivation in children and adolescents is especially undesirable. Growth hormone is responsible for building muscle mass, is indispensable for the restoration of cells and tissues of the body. A small amount of this hormone is constantly produced by the pituitary gland, but high-quality sleep and physical activity make this process more active.
Digestion, weight and appetite
It is well known that excessive craving for high-calorie food and a sedentary lifestyle lead to overweight. But few people are aware that sleep deprivation is also one of the risk factors for obesity. The duration of a night’s sleep affects the level of two hormones that regulate feelings of hunger and satiety – leptin and ghrelin.
It is leptin that sends signals to the brain that the body has already had enough. If a person sleeps less than 7 hours a day, the level of leptin in the body decreases, but instead the concentration of another hormone increases – ghrelin, which stimulates appetite. In addition, if a person does not get a full rest at night, during the day he will feel too tired for an effective workout, which further increases the chances of getting extra pounds.
Sleep deprivation also encourages the body to produce higher levels of insulin after eating (this hormone controls blood sugar levels). Improper concentration of insulin contributes to the accumulation of fat and increases the risk of developing type 2 diabetes.
What happens if you don’t get enough sleep regularly
Cognitive abilities are impaired
If a person sleeps less than 6 hours, his memory and reaction speed are significantly reduced. Scientists from the University of Pennsylvania School of Medicine have found that chronic sleep deprivation affects cognitive abilities exactly as if a person did not sleep at all for 48 hours in a row. According to the observations of scientists, Sleep deprivation complicates the processes of learning, memorization and solving tasks that require mental stress. In addition, sleep deprivation can affect the ability to soberly assess the situation and respond to it appropriately.
The tendency to infectious diseases increases
Experts have calculated that if a person rests less than 7 hours a day, he has almost twice as much chance of catching a cold.
Studies confirm that against the background of chronic sleep deprivation, people become pessimistic, angry, more easily succumb to stress and depression, they often have mood swings and self-esteem decreases. American scientists have calculated that people whose sleep lasts less than 6 hours are 5 times more likely to suffer from depression than others. But at the same time, insomnia in many cases is one of the earliest symptoms of depressive disorder.
There are cardiological diseases
According to the results of a study published in the journal Sleep Medicine by Oxford scientists, people whose sleep lasts 5 hours or less are more likely to develop hypertension than those who sleep at least 6 hours a day. In addition, such people usually have more plaque on the walls of the coronary arteries, which experts associate with increased levels of cortisol (stress hormone). Chronic sleep deprivation increases the risk of heart attacks, strokes, arrhythmias, hypertension.
No wonder all nutritionists and trainers advise their clients not only to follow a diet and a sports regime, but also to get enough sleep. If a person regularly does not get enough sleep, he automatically falls into the risk zone of developing obesity.
The skin condition worsens
After one sleepless night, most people have bags under their eyes, and the skin acquires an unnaturally pale shade. If the sleep deprivation is chronic, the changes on the skin are more noticeable: it becomes dull, fine wrinkles appear, and dark circles appear under the eyes. This is easily explained from the point of view of science. When a person sleeps too little, his body produces a lot of cortisol, and an excess of this hormone causes the destruction of collagen, a protein on which the smoothness and elasticity of the skin depends.
The risk of injury is growing
American researchers studied the condition of a person who did not get enough sleep and compared it with the state of alcoholic intoxication. Scientists say that in both cases, the reaction is noticeably worse. Moreover, they estimated that due to fatigue, about 100 thousand car accidents occur annually in the United States alone, 1,500 of which end in deaths.
Men and women deprived of full sleep, even for a short time, lose interest in sex. The most obvious causes of decreased libido are lack of energy, drowsiness, fatigue and irritability that occur against the background of sleep deprivation. In addition, testosterone levels drop in men due to insufficient rest, which also leads to a decrease in sexual desire.
It was laid down by nature that with the arrival of night, a person should sleep. This has been the case for many centuries. As soon as the sun sank below the horizon and it became dark, a person fell asleep. But with the invention of electricity, people stopped rushing to bed with the sunset, and the period allotted for sleep decreased. Nowadays, healthy sleep has serious “competitors” – the Internet and TV, which are ready to steal our time around the clock. Modern man is ready to sacrifice valuable hours of night rest for the sake of the Internet, games and television, and in the morning to fight drowsiness with large portions of caffeine, thereby bringing himself even more harm.