Is it true that you need to sleep at least 7 hours?

Every day we come with thousands of popular tips, rules, and safeguards, many of which turn out to be delusions. We are launching a series of materials in which we will dissect popular opinions and find out if they are related to reality. Today we figure out how long to sleep and how sleep and life durations are related.

Statistics show that the overwhelming majority of the adult population in developed countries is chronically sleep-deprived. And although the working day in the civilized world continues to decrease, people still sleep less than they should. Someone blames electronic devices with displays that do not allow a person to calm down for this, others talk about the severe stress they face at work and school. Therefore, it is generally accepted that even if you do not get enough sleep on weekdays, you can get more sleep on weekends. The ideal balance is to sleep as much as you can afford. it is impossible to sleep “too much”. If you have rested enough, you will wake up immediately.

Could you sleep as long as you want?

It is most natural for a person to sleep not for 7-8 hours in a row, but twice for 3-4 hours with a break of 1-2 hours. In the 1990s, this conclusion was reached by the American psychiatrist Thomas Wehr, who conducted an experiment by transferring the subjects to conditions without artificial lighting for a month. He found in the documents of the Middle Ages and Modern Times hundreds of references to two sleep segments, while they were always spoken of as something obvious. Scientists suggest that this sleep rhythm helped people better cope with stress. The fashion for long sleep at the end of the 17th century was introduced by wealthy Europeans, followed by the rest, and finally, the tradition disappeared in the late 19th – early 20th centuries, when electric lighting was introduced everywhere.

Recently, a professor at the University of Warwick, Franco Cappuccio, who specializes in cardiovascular diseases, examined 16 studies in which more than 1.1 million people participated in the last ten years. Cappuccio found a direct link between sleep length and human health: those who fit in between 6 and 8 hours felt better than others. This is to be expected, but something else is interesting: the mortality rate among those who slept for more than eight hours was higher than among those who did not sleep enough. As Cappuccio concluded, sleeping too long indicates that a person has health problems – or that he is very tired.

The main thing to understand is how much the duration of sleep is individual. Athletes need more recovery time after grueling workouts than an office worker sitting at a desk all day, and babies need more sleep than older adults. It is unlikely that many people today will be able to switch to two periods of sleep with a break, as it was before the invention of artificial lighting, but if you regularly sleep for more than 8 hours, then this may be a reason to see a doctor. Not to mention the fact that you need to sleep at least 6-7 hours every day, not just on weekends.