8 Hours of Sleep Daily: Necessity or Habit?


It is believed that a person needs at least eight hours of uninterrupted sleep for a good rest. However, a recent research conducted by the American scientists has shown that, in fact, this habit appeared only at the beginning of the 20th century. People used to sleep quite differently before that.


The experts from the American University of Virginia claim that the need for continuous eight-hour sleep is nothing more than a popular misconception, which nevertheless has had a fundamental impact on the modern people. Today, few people feel relaxed after sleeping for less than eight hours. Especially if the person awakens a few times during the night. The researcher from the United States Roger Ekirch proves that waking up in the middle of the night is not only normal, but beneficial as well.

According to the scientist, human sleep has been biphasic since time immemorial. Each period lasted for four hours. During the pause between the time blocks, which usually lasted for at least an hour, people used to pray, dream with the eyes open, talk with the wife, and even visit other people. Ironically, technological progress is primarily to blame for the appearance of the stereotype about the eight-hour sleep. Before the invention of electricity, the city streets and, of course, the houses were dark for 14 hours a day. Especially in winter.

Only the wealthy people, who spared no money on candles, could afford reading in bed before going to sleep. The majority of the people went to bed very early, resulting in the period of 9 to 10 hours spent in bed, including the time of night awakenings. Robert Ekirch managed to collect more than 500 historical documents belonging to different epochs, which referred to biphasic sleep. The representatives of African tribes, the ancient Greeks, and medieval monks used to sleep for four hours with breaks. And none of them complained of insomnia.

According to Ekirch, the rhythm of life has changed as a result of the widespread distribution of electric lamps and lanterns in the late 19th – early 20th centuries, and with the advent of night entertainment industry. People began to go to bed later, and, as a consequence, they got less sleep. It was then that numerous studies appeared, in which the authors claimed the necessity for a person to have continuous sleep.

Nevertheless, people continued to wake up at night. For many, waking up transformed into a problem. In the early 1990-s, the German scientist Thomas Wehr conducted an experiment by making a few dozen volunteers spend 14 hours a day in darkness. After a while, the people themselves switched from the continuous eight-hour sleep to the “two-phase rest”. Robert Ekirch is sure that this type of sleep is natural for human beings.

So what is the advantage of biphasic sleep? The scientist writes that in addition to having better rest, people remember their dreams better, which opens the way for us to comprehend our own subconscious. However, he does not think that modern people have a chance to go back to this model of sleep. The events in the modern world become outdated too fast, and only hermits can afford to sleep for four hours with a break.