There is a Japanese word, inemuri, that translates literally as “sleeping while present.” It means dozing off in a public or professional setting where you are technically required to be awake: at your desk, in a meeting, on the commuter train. What matters is what the sleeping signals. In Japanese professional culture, inemuri has historically been understood as a mark of dedication. The logic runs: you gave so much to your job that your body gave out. The exhaustion is visible proof of commitment.
Cambridge Japanese-studies scholar Brigitte Steger, who has spent decades studying the practice in books and papers, describes a social hierarchy embedded in it: newcomers must remain visibly alert, while senior staff are permitted to close their eyes, and the higher your position, the more freely you may sleep.
Japan, by every large-scale measure of sleep science, is also one of the most sleep-deprived nations on earth, and the two facts are connected.
Inemuri is the cultural rationalization a society reaches when it cannot, or will not, address the structures producing the exhaustion. The honorable public nap works as a coping mechanism, turning a problem the system has left in place into a source of pride.
This same mechanism, in various local forms, operates across much of the industrialized world. And understanding it requires abandoning a persistent fiction in public health: that how much you sleep is primarily about you.
The Map
In 2016, Olivia Walch, Amy Cochran and Daniel Forger of the University of Michigan turned ENTRAIN, a smartphone application they had built to help travelers recalibrate their circadian clocks after crossing time zones, into a tool for comparing sleep across countries. From its anonymized data the team collected the usual bedtimes, wake times and light exposure reported by 8,070 users in about 100 countries. After implausible sleep times and users outside the 18-to-85 age range were screened out, they analyzed the 5,450 who remained and compared the twenty countries with the most respondents. No sleep laboratory had ever gathered a global sample on that scale.
Japan and Singapore occupied the sleep-deprived end of the spectrum, averaging around seven hours and twenty-four minutes, the lowest among the countries compared. The United States clustered toward the middle, at just under eight hours. The Netherlands anchored the other extreme at nearly eight hours and twelve minutes.
That gap may sound modest until it is set against the recommendations. The US National Sleep Foundation puts the healthy adult range at seven to nine hours, and America’s sleep-medicine societies recommend at least seven. At the Japanese average, a large share of the population is sleeping at or below the floor of that range. Japan’s own health-ministry figures suggest the reality is harsher still: in 2019, about 38 percent of men and 41 percent of women reported sleeping less than six hours a night, which suggests the ENTRAIN figure, drawn from a self-selected app user base, flatters the true picture. Compounded over a working life, even a modest nightly shortfall adds up to years of lost sleep.
The data also showed how the gap was built: the variance between countries was driven almost entirely by bedtime, not wake time. Wake times varied far less between countries than bedtimes did, and a country’s average wake time did not predict how long its people slept. What differed was when people went to bed. Social pressures, the researchers concluded, “weaken and/or conceal biological drives in the evening, leading individuals to delay their bedtime and shorten their sleep.”
The easy explanation, that richer and busier nations sleep less, does not hold. Japan is one of the world’s largest economies. South Korea is a global technology powerhouse. Singapore is among the wealthiest places on earth by per capita income. Yet all three sit at the sleep-deprived end of the international comparisons, while the Netherlands, far richer per head than Japan, sleeps significantly more.
Spain makes the point more sharply. The country is synonymous, internationally, with the siesta, a midday rest tradition that ought to make Spain one of Europe’s best-rested nations. Yet another tracking app, Sleep Cycle, places Spaniards among Europe’s shorter sleepers: around seven hours and thirteen minutes of tracked time in bed a night, against about seven hours thirty-seven in the Netherlands and Finland. The head of Spain’s national commission on working hours has claimed a gap of almost an hour against the rest of Europe, though time-use diaries, which count every nap, rank Spain higher. The siesta itself is fading: asked in 2016, 58 percent of Spaniards said they never take one. It has largely abandoned urban professional life, while late bedtime culture has not: dinner at ten o’clock is standard in Madrid, bedtimes follow past midnight, and the alarm still goes off at the same hour as everywhere else.
Spain shows that you cannot read a nation’s sleep from its official customs or its stated values. You have to look at what the daily structure does to the body.
Where the Hours Go
Think of nightly sleep as a budget of hours. Most adults need between seven and nine hours for full cognitive and physiological restoration. The budget is finite and inflexible; it cannot be disciplined into shrinking without cost.
The first thing that draws on it is the commute. People in greater Tokyo who travel to work or school spend about an hour and a half to an hour and forty minutes on a weekday getting there and back, close to fifty minutes each way; the region’s four prefectures hold the four longest figures in Japan’s national time-use survey. That time is gone before anything else claims the evening. The mechanism is arithmetic: a later arrival home pushes dinner, the wind-down and sleep onset later, but the alarm does not move. The working day starts when it starts, so the compression falls entirely on the far end of the night.
When researchers fitted 760 employed adults in the United States with wrist-worn sleep trackers instead of asking them how they slept, each additional hour of daily commuting corresponded to fifteen fewer minutes of sleep on work nights. Apply the same ratio to a Tokyo worker commuting ninety minutes each way and a colleague cycling twenty minutes across Amsterdam, and the Tokyo worker stands to lose about thirty-five minutes of sleep every workday. That comes to nearly three hours a week, and close to six full days of sleep over a working year.
The CDC has mapped short sleep county by county across the United States, and the map shows a different but related pattern. The highest rates of short sleep duration are concentrated in counties across the Southeast and along the Appalachian Mountains; the single highest estimate, 48.4 percent of adults, was in Greene County, Alabama. They are low-income, high-chronic-disease regions: the map of short sleep closely tracks the agency’s maps of diabetes, hypertension, heart disease and depression, and short sleep rises steadily as household income falls and as counties grow more rural. Sleep deprivation in America is also built in, but by different things: in Japan, overwork and commute time; in rural Appalachia, poverty and the chronic illness that travels with it.
The commute decides when workers get home; office culture decides when they may leave. In Japan and South Korea, the dominant professional metric is visible presence rather than output. Leaving work before your manager is socially coded as insufficient dedication and, in many contexts, as outright disloyalty. This form of presenteeism keeps bodies at desks long after minds have effectively clocked out. Japan has a word for death from overwork: karoshi. South Korea’s equivalent is gwarosa. Neither is a figure of speech: in fiscal year 2025, Japan’s Ministry of Health, Labour and Welfare officially recognized 1,310 cases of overwork-related illness and death, including a record 1,082 mental-health cases, and the total is almost certainly an undercount given the evidentiary bar for official recognition. South Korea, confronted with some of the longest average working hours in the OECD, legislated a reduction in the maximum working week from sixty-eight hours to fifty-two in 2018.
These words, karoshi and gwarosa, exist in Japanese and Korean because the societies needed them. No equivalent has entered mainstream Dutch or Finnish usage because the concept has no comparable social purchase there.
The incentive structure driving presenteeism is rational, which is what makes it so durable. Individual workers who stay late in these systems are responding correctly to a career environment in which leaving on time carries professional consequences. The problem lies in a system of incentives that was constructed, maintained by institutional inertia, and negotiated daily by individuals who did not build it and cannot dismantle it alone.
Two further forces compound the effect, both operating below the level of conscious choice. The first is light. The human circadian clock evolved, long before electric light, to read the setting sun as a signal to begin the biological preparation for sleep: a cascade of melatonin release and core temperature reduction that takes hours to complete. In central Tokyo or Seoul at midnight, that signal is hard to find. LED street lighting, convenience store fluorescents, digital billboards, and smartphone screens saturate the nighttime environment with blue-spectrum light that actively suppresses melatonin production. The Walch data point the same way: users reporting that they typically spent their days in indoor light went to bed later and slept less than those reporting outdoor light. The city’s artificial light, imposed by infrastructure and technology decisions made by governments and corporations, works against the biological timing the body is trying to maintain.
The second is alcohol. In cultures where after-work group drinking is institutionalized, such as Japan’s izakaya tradition and South Korea’s hoesik gatherings (which four in ten Korean workers in one 2020 survey said they worried about skipping), alcohol systematically distorts sleep architecture even when total logged hours appear adequate. Alcohol helps people fall asleep faster, but it delays REM sleep, a stage closely linked to memory consolidation and emotional processing, reduces it at moderate and heavier doses, and it fragments the second half of the night. Sleep after heavy drinking is physiologically inferior to undisturbed sleep: the tracker may record eight hours, but the night the brain gets is shorter and more broken. For the worker who cannot professionally absent herself from the hoesik without flagging her disengagement, the drinking is not a personal choice.
These forces are built into the shape of a working day, and they compound: the commute and the office take the hours, and light and alcohol degrade the sleep that is left.
The Manufacturing of Exhaustion
That still leaves the question of why different nations built such different arrangements: why Japan constructed a professional culture of visible exhaustion while Denmark built one of protected departure times, why American cities sprawl for an hour from their downtowns while Dutch ones compact around cycling distance.
The answer is in labor history. The belief that rest is waste, that time not producing is time stolen, did not emerge from human nature. It was installed, with considerable effort, during industrialization, at the moment factory owners needed to convert agricultural workers into industrial ones.
Agricultural time is irregular, seasonal, rest-interspersed: you work hard at harvest, rest in the slow months, stop when it gets dark. Factory time is clock-governed, continuous, and indifferent to biological rhythm. Converting workers required physical relocation and, with it, a moral reorientation: workers had to be taught to feel that rest was laziness and long hours a virtue, until productivity became identity.
That message, compressed by the twentieth century into “I’ll sleep when I’m dead,” “you snooze, you lose” and “rise and grind,” is a historical product, and it spread unevenly across nations depending on the strength of the forces that resisted it.
Scandinavian and Northern European labor movements, from the early twentieth century onward, fought explicitly for the separation of rest from shame. The eight-hour day, the protected weekend, collective agreements that cap after-hours availability and the social expectation of leaving on time were political victories, won in specific negotiations against employers who argued, with the same logic deployed in Tokyo offices today, that commitment required unlimited availability. The countries that won those arguments more completely, and encoded the results more durably in law and collective norm, tend to be the countries sleeping more today.
Japan’s trajectory was different. The postwar economic reconstruction of the 1950s and 1960s fused corporate loyalty with national survival in a way that made individual sacrifice to the employer feel patriotic, even necessary. The country had been leveled and needed to rebuild; the salaryman’s grueling hours were framed as the civilian equivalent of wartime service, and the culture absorbed that framing and kept it. South Korea’s rapid industrialization in the 1960s and 1970s taught the same lesson: overwork as national duty, rest as self-indulgence. The American South and its adjacent Appalachian region, the most sleep-deprived part of the United States, carries a different historical weight: decades of disinvestment, extractive labor markets, and the physical toll of chronic poverty on sleep quality.
Inemuri itself is old: Steger notes that napping in Japanese historical sources seems to have been widely taken for granted, and that young samurai scholars were praised for cutting their sleep to study even when they dozed off in lectures. What modern office culture added was a new role for it. In workplaces where diligence is measured in hours endured, an old tolerance for dozing became a way of dignifying the results: the sleeper at the meeting table signals, in Steger’s reading, that they have worked themselves to exhaustion yet still have the moral strength to remain present. That role is contingent and, in principle, reversible.
Consider clean water. We do not diagnose populations without access to clean water as having a hydration discipline problem. We understand water as infrastructure: its provision depends on collective investment, its failure is recognized as a systemic failure, and we hold governments accountable for it. Sleep deserves the same frame. Its provision depends on how we build cities, structure labor markets, design commutes, and regulate the hours at which the sky is permitted to go dark.
The Bill
After seventeen hours awake, which is late evening for someone who rose at six, a worker’s performance on some cognitive and motor tests has degraded to roughly the level seen at a blood alcohol concentration of 0.05 percent, the legal drunk-driving threshold in most of Europe. Researchers compared the performance of 39 transport-industry and army workers through a long stretch without sleep against their performance after measured doses of alcohol; after seventeen to nineteen hours awake, their impairment was equivalent to or worse than at that threshold.
That worker has not had a drink. She has been awake since before six, commuted for an hour in each direction, stayed until the manager left, and is now, by her own nervous system’s biological reckoning, as impaired as someone over the limit. Nobody will breathalyze her.
In 2016, RAND Europe published one of the most widely cited economic quantifications of this, modeling the relationship between population-level sleep deprivation, workplace productivity, mortality risk, and GDP across five OECD countries. By its estimate, the United States was losing up to $411 billion a year to insufficient sleep. Japan was losing up to $138 billion, an even larger share of its economy. Germany, the United Kingdom, and Canada added tens of billions more, bringing the annual toll across the five countries to as much as $680 billion.
The losses came through higher mortality and lower productivity, and the productivity losses came both from absenteeism, workers staying home sick, and from presenteeism: workers showing up and functioning at reduced capacity. A sleep-deprived worker makes more errors, processes information more slowly, misses contextual cues, and makes worse judgments under uncertainty, and most of those errors go unseen.
In industries where errors are catastrophic, the record is explicit. In 1988 a committee of sleep researchers warned that catastrophic human errors cluster at the hours when the brain’s drive to sleep is strongest. The US Institute of Medicine later listed the nuclear accidents at Three Mile Island and Chernobyl among disasters partially attributed to sleep loss and night-shift performance failures.
The National Transportation Safety Board’s investigation of the 1989 Exxon Valdez grounding concluded that the third mate failed to maneuver the vessel “because of fatigue and excessive workload.” He may have had as little as five or six hours of sleep in the previous twenty-four, and the board faulted Exxon Shipping Company for failing to provide “a rested and sufficient crew” on a ship run with a reduced crew complement. A human-factors review published with the Presidential Commission’s report on the Challenger disaster found that, because of the January 27 launch scrub, certain key managers in that evening’s teleconference, the one that cleared the launch for the next morning, had obtained only minimal sleep the night before or had been awake and on duty for extended periods. It concluded that the willingness of NASA employees to work excessive hours “raises serious questions when it jeopardizes job performance, particularly when critical management decisions are at stake.”
The undocumented equivalents occur in every sleep-deprived workforce, invisibly, every day: the misread scan, the missed drug interaction, the bridge inspected by someone at hour nineteen of a shift.
Proportionally, Japan loses more of its GDP to sleep deprivation than the United States, with RAND’s upper estimates putting the toll at 2.92 percent versus 2.28 percent. A nation that prizes visible, relentless work is destroying a larger share of its output through the fatigue that performance creates than one that works somewhat less intensely.
A system built for maximum output is compounding its own losses night after night, and the workers who stay late are the ones left with the bill.
The Convenient Exhaustion
There is an industry, valued by market analysts at anywhere from $80 billion to nearly $600 billion a year depending on what is counted, built on the opposite premise.
The sleep optimization economy sells mattresses engineered with proprietary foam layers, wearable trackers that grade your sleep like a homework assignment, melatonin supplements, apps coaching breathing techniques and sleep hygiene protocols, weighted blankets, white-noise machines, blackout curtains and private courses of cognitive behavioral therapy for insomnia, a treatment that works for the disorder it targets. Nearly all of it is sold on one premise: that insufficient sleep is a personal optimization problem.
The individual framing is not sinister in isolation. Good sleep habits are useful at the margins. Yet the same framing that sells mattresses is structurally useful to interests far larger than the mattress industry.
A workforce that attributes its exhaustion to personal failure is slow to demand shorter commutes or to organize around labor reform, and slower still to pressure employers to cap working hours, urban planners to build denser housing, or governments to regulate artificial light at night. It buys a better pillow, recalibrates its bedtime routine and accepts that the conditions producing its tiredness are facts of nature rather than outcomes of policy. It is what happens when the costs of a structural failure are relocated from the system that produced them onto the individuals experiencing them.
Structural interventions work, and they work fast. When Seattle’s public high schools moved the first bell almost an hour later, to 8:45 a.m., students tracked with wrist monitors gained a median of thirty-four additional minutes of sleep per school night. They got it by waking later rather than going to bed earlier, in line with the documented biological reality of adolescent circadian timing. Final biology grades rose 4.5 percent, and at one of the two schools studied, tardiness and first-period absences fell. The change asked no extra effort of students; it required only a new schedule. South Korea’s 2018 cap on the working week cut the share of employees working beyond fifty-two hours within a few years, though OECD-led evaluators judged that it had “reduced but far from eliminated” such marathon weeks. RAND’s own modelling estimated that delaying US school start times to 8:30 a.m. or later would add $83 billion to the US economy within a decade.
These interventions meet stiff institutional resistance: school districts cite bus schedules, employers cite global competitiveness, and urban developers have no interest in revisiting land use decisions made sixty years ago. The resistance is most concentrated and best funded where the structural change would extract the most value from those currently profiting from the status quo: developers whose models assume sprawl, and employers who pay for presence rather than output.
A fatigued workforce is also an easier one to manage. Nobody needs to design it that way; the incentives line up on their own, because exhausted workers have less left over for organizing, for sustaining a long dispute, or for blaming anyone but themselves.
The Infrastructure of Night
Return to the Tokyo train. The commuters asleep against their neighbors’ shoulders are not weak or undisciplined, and they have not failed at sleep hygiene. They are living inside a daily geometry that makes adequate sleep mathematically improbable: a commute that consumes the better part of two hours, an office culture that punishes departure, a city that never goes dark, a professional social calendar that runs until midnight, and a culture that turned an old tolerance for dozing into a way of making exhaustion beautiful.
Inemuri, in its modern office form, is the monument to that turn.
The geography of sleep is the geography of power: who gets to rest, who is required to keep going, and who profits from the difference. It is drawn in transit plans, office hours and labor agreements, mostly by people other than the ones losing it.
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