It is a common belief that after a busy day at work you can sleep off on the weekend or on vacation. We decided to check whether, from a scientific point of view, lack of sleep on some days can be compensated by long sleep on others.

Many looking forward waiting another weekend, dreaming of getting some sleep. After all, it is customary to compensate for lack of sleep on weekdays by sleeping longer on Saturday and Sunday, as well as on holidays. According to survey job search service SuperJob, 11% of Russians do not want to spend time with their family or go to nature on the weekend, but to get some sleep. Survey of the service "Rabota.ru" showed: 19% of respondents reported that they do not get enough sleep regularly, another 61% get enough sleep periodically, only 18% of respondents feel well-rested all the time. Plans sleep on weekend dedicated huge quantity memes and comic pictures. For example, one one of the most popular jokes beats homonymy of the word “get enough sleep.”

Lack of sleep is associated with a range of health problems. In a dream, the brain successfully gets rid of from beta-amyloids, the accumulation of which is associated with the occurrence of Alzheimer's disease. Just one sleepless night (31 hours without sleep) increased the amount of beta-amyloid in the brains of volunteers by 5%. A night without sleep equal to according to the destructive effect on the body of six months of eating fast food: both of them reduce glucose tolerance and lead to a pre-diabetic state. Lack of sleep leads and to mental changes: a person who regularly does not get enough sleep loses the ability to distinguish between a neutral or benevolent facial expression of an interlocutor and tends to interpret the facial expressions of other people as more dangerous. Risk of heart attack among those who sleep less than six hours increases by 20% and weight by 12.5 lbs. annually (about 5.5 kg). Therefore, scientists devote a lot of research to sleep.

One of the largest analyzes spent in Sweden. For 13 years, scientists observed 43,880 volunteers, assessing a variety of parameters of their lives: sleep duration, body mass index, smoking, level of physical activity, working night shifts, etc. It turned out that in a group of people under the age of 65 who slept five or less hours a day, the risk of death from all causes increased by 52% compared with this parameter in those who slept seven hours. At the same time, for those who slept during the week on the weekend (slept eight or more hours), this risk did not increase, remaining at the average level for the population.

However, a significant difference between the duration of sleep on weekdays and weekends, as well as different times of going to bed, leads to such a condition as social jetlag. Typically, jet lag is a feeling of exhaustion, accompanied by a variety of unpleasant symptoms, after a significant change in time zones due to airplane travel. Jet lag even indicated in the International Classification of Diseases under code 7A65 in the section of sleep-wake cycle disorders. With social jetlag, a person does not fly anywhere, but goes to bed on weekdays, for example, at 22:00, then wakes up at 6:00 in the morning, and on weekends he randomly changes this rhythm and goes to bed at 3:00 in the morning and sleeps until noon. Thus, he seems to cross five time zones, which is equivalent to traveling from Yakutsk or Chita to Moscow. Returning to the weekday schedule on Sunday evening, he again “flies” - from Moscow to Yakutsk.

Social jetlag is extremely dangerous for the body: according to calculations According to scientists, every hour of difference between going to bed and waking up on weekdays and weekends increases the likelihood of cardiovascular disease by 11%. Social jetlag (understood as the difference between the average number of hours of sleep on weekdays and weekends) also increases double the risk of developing type II diabetes in the age group under 61 years of age. Brazilian researchers who studied social jetlag discovered its connection with overweight and obesity. Chicago scientists studied activity of American Twitter users, analyzing the time of publication of posts with geotags, and found that the level of social jetlag correlates with excess weight. Social jetlag turned out to be is also associated with changes in blood parameters: low levels of high-density lipoprotein (bad cholesterol), higher levels of triglycerides (leading to the development of atherosclerosis and heart and vascular diseases), higher fasting plasma insulin and insulin resistance (signs of the possible development of diabetes).

Jet lag causes disruptions not only in humans, but also in the bacteria that inhabit our gastrointestinal tract. Israeli scientists conducted a series of experiments on mice and a small group of volunteers, studying their intestinal microflora after random jet lag. Although intestinal bacteria live their entire lives in the dark, changes in time zones and routines have affected them as well. At the wrong time (before bedtime), those bacteria that are responsible for the breakdown of food became active and demanded to go eat, and during the day, on the contrary, “night” bacteria woke up, which, instead of digestion, are normally responsible for restoration work and cleansing the body. American scientists notedthat chronic jet lag in mice after three months led to the development of non-alcoholic fatty liver disease, which in some cases caused the development of hepatocellular carcinoma, a type of liver cancer.

And although the desire to get enough sleep on the weekend, as Swedish scientists have discovered, can reduce the risk of premature death, there are many other health problems from which long sleep on the weekend does not save us, and sometimes even creates them. A group of scientists from the University of Colorado dialed 36 volunteers aged 18 to 39 years. The volunteers were divided into three groups: the first were allowed to sleep for nine hours every night, the second were limited to five hours, the third group was given only five hours of rest for five days, and the remaining two days they could sleep as much as they wanted. Members of both sleep-deprived groups gained an average of a kilogram of weight over the nine days of the experiment. Those who got enough sleep improved their health a little on weekends, but all the improvements disappeared as soon as they went back to five hours of sleep. For example, insulin sensitivity in the group with five hours of sleep decreased by 13%, and in the group of those who were able to catch up on sleep deprivation, the decrease ranged from 9% to 27%. Professor of Integrative Physiology and Director of the Sleep and Chronobiology Laboratory Kenneth Wright, one of the study's authors, summed up the results of the experiment: "Living with a yo-yo (a pendulum-type toy) - changing the time we eat and changing our circadian clock on weekends, and then returning to insufficient sleep - is itself extremely destructive." Agree with him and Michael Tvery, director of the National Center for Sleep Disorders Research: “Frequently changing sleep schedules are a form of stress associated with metabolic abnormalities.” At the same time, scientists admit that extended sleep on weekends can help those who do not get enough sleep on weekdays not regularly, but only one day a week. However, this idea needs careful research.

Thus, a consistent schedule with the same bedtime and wake-up time protects against a significant number of health problems. Long sleep on weekends will definitely not help improve health, undermined by constant lack of sleep on weekdays. At the same time, if in general your sleep schedule is balanced and only sometimes there is not enough sleep on weekdays, then it may be a good idea to sleep longer on the weekend. However, scientists do not yet have experimental evidence of the benefits of this approach.

Cover image: CyprusMail