(NaturalNews) For decades, experts have told us that in order for our bodies to perform at their maximum level, we need at least eight hours of uninterrupted sleep a night. Increasingly, data suggests that old standard is not historically accurate.
A growing body of both scientific and historical research and information indicates that eight continual hours of sleep may be unnatural, and that waking up in the middle of the night could actually be good for a body.
Current research into the subject began in earnest in the early 1990s, the BBC reports, when psychiatrist Thomas Wehr began conducting experiments in which a group of people were placed in darkness for 14 hours every day for a month. It took a bit of time for them to regulate sleep but by the fourth week, the research subjects had settled into a distinct sleeping pattern.
Subjects slept for about four hours, then woke up for one or two hours before falling asleep again for another four hours.
Eight-hour block of sleep relatively new concept
Sleep scientists were impressed with the study's results but the general public still came away with the notion that eight hours of uninterrupted sleep is a must in order to maintain peak functionality and health.
Then, in 2001, historian Roger Ekirch of Virginia Tech University, in a paper drawing on 16 years of research, revealed "a wealth of historical evidence that humans used to sleep in two distinct chunks" of time, the British news service reported.
Ekirch published a book, "At Day's Close: Night in Times Past," four years later, in which he revealed more than 500 references to a segmented sleeping pattern. Such references were gleaned from diaries, medical books, court records and literature, the latter from Homer's Odyssey to an anthropological account of modern tribes located in Nigeria.
The references were like those reported by Wehr's subjects in that they describe a first sleep which began about two hours after dusk which were followed by waking periods of one to two hours, then a second block of sleep.
"It's not just the number of references - it is the way they refer to it, as if it was common knowledge," Ekirch said.
During the waking period people were very active, the research suggests. Often they would get up to go to the restroom, smoke and sometimes even visit neighbors, though most people, according to records, stayed in bed to read, write letters or pray.
Not all of the in-between waking hours were spent in solitude; often people talked to bedfellows or had sex. A physician's manual from 16th century France, for instance, advised couples that the best time to conceive a child was "after the first sleep," not at the end of a long day, "when they have more enjoyment" and "do it better."
By the 1920s, according to references, the idea of first- and second sleep had completely receded from social consciousness. Ekrich attributes that shift to better street lighting, domestic lighting and a surge in so-called coffee houses, many of which were open all night.
Per the BBC:
As the night became a place for legitimate activity and as that activity increased, the length of time people could dedicate to rest dwindled.
Nearly one-third of all American working adults get six hours or fewer a night
Historian Craig Koslofsky, in his new book, "Evening's Empire," discusses how this transformation happened.
"Associations with night before the 17th century were not good," he says, noting that night brought out people of disrepute, such as criminals, drunks and prostitutes. "Even the wealthy, who could afford candlelight, had better things to spend their money on. There was no prestige of social value associated with staying up all night."
That changed with technology.
"People were becoming increasingly time-conscious and sensitive to efficiency, certainly before the 19th century," says Ekirch. "But the industrial revolution intensified that attitude by leaps and bounds."
The Centers for Disease Control and Prevention says about 41 million Americans, or nearly one-third of all working adults, get six hours of sleep or fewer per night.