Scientists - human needs complete darkness during sleep

2024 Author: Seth Attwood | [email protected]. Last modified: 2023-12-16 15:55

People who do not sleep in complete darkness have an increased risk of developing cardiovascular and cancer diseases. In addition, those who get up before sunrise may also have health problems, experts interviewed by RIA Novosti told RIA Novosti.

"Now more and more data appears that there is a fairly clear connection between excessive illumination, primarily, of course, in large cities, and the risk of developing certain diseases, primarily cardiovascular and oncological," said the head Center for Sleep Medicine, Lomonosov Moscow State University, cardiologist, somnologist, candidate of medical sciences Alexander Kalinkin.

He explained that light is the main regulator of the hormone melatonin, which signals the body's cells that night has come. According to the expert, each cell works according to its own clock, so that the cyclicity of some processes differs from the 24-hour cycle, and melatonin gives a command to regulate this cycle.

"Not only is the work of functional systems changing - cardiovascular, respiratory, and so on, but also the activity of the genome changes, when we sleep, the activity of certain genes changes. Therefore, if the light is excessive, and in the evening we use bright lighting, computers, gadgets, this shifts the phase of melatonin production to later hours, and accordingly, causes sleep problems in a person, "Kalinkin said.

Wake up after sunrise

As noted by the chief researcher of the Institute of Ecology and Evolution named after A. N. Severtsov of the Russian Academy of Sciences, Doctor of Biological Sciences Vladimir Kovalzon, many studies show that if people get up after dark, then they are more likely to have impaired immunity and the occurrence of depression.

"The problem is that we live in such a temporary regime, when already now schoolchildren and many working people wake up before sunrise, and we are arranged in such a way that we need to get up after sunrise so that it shines, because sunlight restarts our biological hours, "said Kovalzon.

But electric light, he explained, is very different from the sun and does not have such an ability.

"The biological clock is set for most people not at 24 hours, but at 25, and every morning we need to bring up the arrows to keep pace - when we open the curtains, the sunlight, very bright, restarts the biological clock, and then we we translate the arrows at normal time ", - said Kovalzon.

Night work threatens cancer

Experts call work at night even more hazardous to health. According to Mikhail Poluektov, head of the sleep medicine department of the First Moscow State Medical University named after Sechenov, replacing sleep with any kind of wakefulness contradicts the work of the body's internal clock.

“Regardless of whether we want to sleep or not, the cells of our body switch to night mode in the dark, this is controlled by a genetic mechanism that is inside each cell. No matter how we try to change our habitual biorhythms with our behavior, we cannot do it. , - said Poluektov.

If a person works at night and sleeps during the day, then a mismatch occurs in the body, which is called "desynchronosis", the expert explained.

According to him, the World Health Organization has recognized that shift work is a potentially oncogenic type of activity, it increases the risk of developing certain tumor diseases.

"In particular, it has been shown on breast tumors in women who work night shifts. It was about nurses and flight attendants. These risks increased by 40 percent for nurses and 70 percent for flight attendants, "Poluektov said.

The best time to sleep

The best time to fall asleep, according to experts, is determined by the strengthening of the corresponding biorhythms.

"At 21: 00-22: 00, the secretion of the hormone melatonin begins, after 22 hours, when its level is high enough, the most favorable conditions for falling asleep are created. In addition, the rhythm of body temperature is important, it also begins to change in the evening hours, internal body temperature falls, and, accordingly, it makes it easier to fall asleep, this also happens after 22 hours, "- said Poluektov.

He added that scientists were conducting research in primitive societies - tribes in Africa and South America. These data showed that the time of falling asleep in people who are devoid of the influence of civilization is determined not by the moment of sunrise and sunset, but just by a decrease and increase in the internal body temperature.

How much to sleep

The general recommendation for the duration of sleep, which is given by experts, is from seven to nine hours a day, but six and ten hours are acceptable.

"We sleep in cycles, a cycle takes an hour and a half, an average person sleeps five cycles a night - that's about eight hours, but there are people who don't have enough five cycles, they need six, such people are 30 percent. And there are people who get enough sleep in four cycles., they are few. It depends on the genes, we are all arranged in different ways, "- said Kovalzon.

Long sleep, according to Kalinkin, is often a concomitant pathology and is associated with some kind of chronic inflammatory process or other diseases, so long sleep is not always useful.

Poluektov, in turn, noted that people who do not have the opportunity to sleep normally during the week can sleep off on weekends. This will partially offset the weekly lack of sleep.

“But this triggers the mechanism of insomnia, because the later a person gets up on weekends from Friday to Saturday, from Saturday to Sunday, the less sleep pressure in the evening hours. Accordingly, it is difficult for a person to fall asleep at the usual time; for a long time and falls asleep at later hours than before, and in the morning he gets up for work on Monday, so his sleep is reduced and he gets up tired, sleepy, overwhelmed, Kalinkin specified.

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