From the time that we’re very young, it’s drilled into us that eight hours of sleep a day is the backbone of healthy functioning. It’s the line used to get overactive children to go to bed, to stop teens from staying up into the wee hours of the morning, and make us ready for work in the morning. However, despite it being such a ubiquitous piece of advice, the last few decades have thrown up evidence to suggest the benefits of the eight hours pattern may be little more than myth.
In the early 90s, an experiment was conducted by psychiatrist Thomas Wehr, in which people were subjected to darkness for fourteen hours a day, every day, for a month. After four weeks it was found that the subjects had settled into a sleeping pattern. It consisted of sleeping for four hours, waking up for another hour or two, and then going back to sleep for another four. This was an odd development, given that one would assume that if an eight-hour block of sleep were the most natural and efficient, the body would naturally settle into that rhythm.
A different study
However, in 2001 a historian call Roger Ekirch from Virginia Tech published a paper suggesting humans used to sleep in two chunks, and had done for a long time. Ekirch put forward historical evidence that for a great deal of human existence, it was well-known that the ideal way for humans to sleep was in two chunks, with a break in-between. People would go to bed around dusk, and wake from their “first sleep” a few hours later. They would be reasonably active for an hour or two – reading, writing, praying, and even visiting their neighbors. Afterwards they would begin their “second sleep”, for a few hours more.
Around the late 1600s, this activity began to lessen. The change is typically attributed to the advent of street-lighting, which made it easier to be out at night. Where before, the night had been unsafe or unsavory, lighted streets made it much safer for people to go out after dark and socialize. People began to seize the opportunity to go out and be active at night, and by the end of the 17th century, over 50 cities and towns in Europe had streetlights.
This desire to be active was also influenced by the industrial revolution. The industrial revolution, which promoted growth and productivity at all costs, promoted efficiency and activity as exemplary character traits. A practice as indulgent as the two-sleep system would therefore be unthinkable.
Goodbye two-sleep system
Eventually, the two-sleep system faded away entirely. However, this might not have been for the best. It has been suggested that a habit of sleeping in one block, coupled with an abundance of electric light, may be responsible for sleep disorders such as insomnia. Waking up in the night is a natural phenomenon, and the two-block sleeping system may have been an excellent way of naturally regulating stress. As such, the eight-hour sleep pattern may actually be doing us more harm than good.
Ultimately then, it seems that a solid eight hours of sleep might be more trouble than they’re worth. Far from a naturally beneficial way of sleeping, it appears to be an unnatural development with a detrimental effect on our health. The best thing for people in the future may actually be to return to our former way of sleeping. We’ll be in bed if you need us.