Updated at 11:23 a.m. ET on January 28, 2022.
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Aat 3 a.m. I’m shaken awake. The room is dark and still. I grab my phone and scan the sports scores and Twitter. Still awake. A faceless doctor whispers in my head: To beat middle-of-the-night insomnia, experts say you have to get out of bed… I’m getting out of bed. I pour a glass of water and drink it. I go back to bed. Still awake. Maybe you know the feeling. Like millions of Americans and hundreds of millions around the world, I suffer from so-called wake-ups-in-sleep that can keep me awake for hours.
One day I was researching my nighttime issues when I discovered a cottage industry of writers and sleep pirates claiming that sleep is a nightmare because of the Industrial Revolution, of all things. Trials in The Guardian, CNN, The New York Timesand The New York Times magazine recommended an old fix for restlessness called “segmented sleep”. In pre-modern Europe, and perhaps centuries earlier, people routinely fell asleep at nightfall and woke up around midnight, only to go back to sleep a few hours later, until morning. They slept a bit like me, but they were zen about it. Then, according to the hackers, modernity came along and ruined everything by pressuring everyone to sleep in one big chunk.
The romanticization of pre-industrial sleep fascinated me. It has also integrated into a popular model of contemporary internet analytics: If you feel a moment of inconvenience, blame modern capitalism first. So I contacted Roger Ekirch, the historian whose work opened the field of segmented sleep more than 20 years ago.
In the 1980s, Ekirch was looking for a book about the night before the industrial revolution. One day in London, browsing public records, he came across references to “first sleep” and “second sleep” in a crime report from the 1600s. He had never seen these phrases before. When he broadened his search, he found mentions of first sleep in Italian (first sound), French (first sleep), and even Latin (first sleepy); he found documentation in Africa, the Middle East, South Asia and Latin America.
When sleep was split into a two-act play, people were creative in how they spent the intermission. They didn’t have anxious conversations with imaginary doctors; they actually did Something. During this sleeps, or “wake-sleep”, people would get up to pee, hang out by the fire, have sex, or pray. They pondered their dreams and mingled with the spiritual world, both divine and diabolical. In the 1540s, Martin Luther wrote of his strategies for warding off the devil: “Almost every night when I wake up…I drive him away instantly with a fart.”
Sleep writers today often use Ekirch’s research to suggest that segmented sleep (or, as Ekirch calls it, biphasic-two-stage sleep) is old, and single sleep is new, and so today’s sleepers do it wrong. But that’s not the whole story, he told me.
Preindustrial sleep was nothing to romance. Death has stalked our sleep for centuries. Nighttime crime was rampant, and the house itself was a death trap, as sloppy construction left houses vulnerable to fire, leaky roofs, horrendous heat or cold, and what Ekirch calls “the trifecta.” winner of modern entomology: fleas, lice and bedbugs.” As for this romantic French sleeps, it was functionally a second day at work for many women, who got up at midnight to finish household chores. And ancient sleeping pills, such as poison leaves and various opiate concoctions, were about as likely to kill you as they were to induce REM.
Beginning in the 1700s, the Industrial Revolution – its light, its caffeine, its clocks and above all its working hours – took Europe’s biphasic sleep into its hairy arms and blended the two phases together. A booming economy made productivity a virtue and instilled “a growing sense of time consciousness” in the West, Ekirch told me. In the mid-1800s, the “Early Rising” movements had taken off in England and America. New artificial lights delayed bedtime, while new factory schedules demanded an early wake-up call. The enlightened world has also altered our internal clocks. “Every time we turn on a light, we inadvertently take a drug that affects our sleep,” said Harvard sleep scientist Charles Czeisler. When a 1990s study at the National Institute of Mental Health deprived a cohort of male subjects of light at night, their sleep became segmented within weeks.
It makes it seem like segmented sleep is the natural habit of mankind, and that the industrial revolution and modern capitalism have robbed us of our perfect rest.
But humans have never had a universal method of sleep. A 2015 study hunter-gatherer societies in Tanzania, Namibia, and Bolivia found that most foragers enjoyed a long sleep. Two years later, another study found that a rural society in Madagascar practiced segmented sleep. Two years later, a study found that indigenous residents of Tanna in the South Pacific had largely uninterrupted sleep.
Even within pre-industrial Europe, sleep contained multitudes. Reviewing the diaries of European writers such as Samuel Pepys and James Boswell, Ekirch found several allusions to unified sleep. Summarizing this complicated literature, he told me that “sleep patterns in non-Western cultures seem to have been much more diverse” than those in Europe, but really were diverse everywhere.
There is no evidence that sleep was universally segmented, and there is also little evidence that segmented sleep is better. A 2021 meta-analysis of studies on biphasic sleep schedules found that segmented sleep subjects actually reported “lower sleep quality…and spent more time in lighter sleep stages.” A reasonable conclusion is that biphasic sleep is like anarchic foraging: both could have served some ancient populations some of the time, but none of them offers a clear solution to modern problems.
I asked Ekirch this question: As the historian most associated with biphasic sleep, has his research encouraged him, a spouse, or a friend to become a biphasic sleeper? “Not at all,” he said. “At no time in history have human sleeping conditions been better than today.” Compared to 99% of our ancient ancestors, we have better beds, better blankets, better homes, and fewer nocturnal pests. If the goal of sleep is mental and physical well-being, “there is very good reason to believe that uninterrupted sleep at night best achieves this outcome,” Ekirch told me.
Jhe woke up from sleep preindustrial and postindustrial history is a simple, short and coherent message: Sleep is adaptable, but improves with routine. Different tricks work for different tribes, but at the end of the day, we’re a diverse species united by a common circadian rhythm that craves consistency. “Sleep is very flexible, when you look cross-culturally,” said Dorothy Bruck of the Australian Sleep Health Foundation. “Your body really likes routine. Find what works for you and stick to that routine.
I’ve spent countless hours obsessing over my sleep, tracking my sleep quality on fancy devices, and reading (and reading and reading) about what I can’t do well. Sleep optimization can backfire by creating instant pressure to solve the problem of wakefulness like trying to solve a Rubik’s Cube against the clock. As any insomniac knows, “trying” to fall asleep is a self-defeating paradox. Insomnia is a beast that feasts on its own self-generated anxiety.
When I reached out to Ekirch, after a bad night’s sleep, I hoped the historian might have some practical advice. He did not do it. History is not a self-help book. But it has its own weird comforts, and our correspondence has been profoundly helpful in another way.
Ekirch told me that he had heard many people say that just knowing the history of segmented sleep was his own relief. “Fortunately, there are growing reports from North America, Western Europe and Australia that knowledge of this pattern has actually helped to alleviate anxiety, allowing some people to fall back asleep. easier,” he said. Rather than seeing the legacy of pre-modern rest as an instruction manual, I see it as a balm. My 3 a.m. awakenings are not an unnatural mess, but an ancestral echo. Maybe this is something to tell myself in the middle of the night, instead of fighting the sleep doctor in my head: Everything will be fine. We’ve been here before.
This article originally stated that Martin Luther wrote about his strategy to ward off the devil in the 1550s. In fact, Luther died in 1546 and the quote was published posthumously.