Hardly a day goes by without some new story about sleep in the papers, on TV or in our news feeds. Sleep is everywhere. We’re told relentlessly how much of it we need, what will happen if we don’t get it, and how much the economy loses through tired workers. Sleep experts broadcast their advice and opinions as if some new philosopher’s stone has been found, and sleep books now grace both bestseller lists and bedside tables.

Adverts for mattresses, once a rarity, now regularly punctuate commercial breaks and the global sleep aid industry will reach an estimated $76bn this year. Just as the media constantly tell us what food we should eat and what exercise we should take, we are now instructed on how and when we must sleep. Whereas a few decades ago there were only a handful of sleep disorders that one could suffer from, today there are more than 70. And with more disorders come more cures, more experts, more revenue.

Companies boast of their new sleep policies, with sleep hygienists eager to get into the boardroom. US insurance giant Aetna, which has almost 50,000 employees, gives them a bonus for getting more sleep, with workers receiving an extra $25 per night if they manage to sleep 20 seven-hour nights or more. If shut eye is a problem, don’t worry, we are told, as once your sleep tracker identifies you as insomniac, you could receive cognitive therapy via your smartphone that will help you sleep healthily.

When I started to research this field some years ago, I was struck by the richness of the questions that sleep poses and by the sense of dialogue that characterised the early work. Physiologists, psychiatrists, psychologists, psychoanalysts and biologists would sit around the same table, pitching hypotheses and comparing their data. Although this golden age of sleep science would end by the 1980s, until very recently textbooks still acknowledged that why we sleep remains a mystery and that no adequate explanation had yet been found.

At one US insurance giant Aetna, workers receive an extra $25 per night if they sleep 20 seven-hour nights or more

Today this has changed. Sleep is not only presented as a problem solved, but as the road to one’s own personal salvation. While spas and wellness centres were once the destination where privileged people were supposed to go to find peace, it is now sleep itself that is marketed as one’s own individual retreat. Sleep-help books promise a nurturing rest if we follow their instructions, yet these almost always turn out to be well known or obvious behavioural tips that could be gleaned from the internet in a matter of seconds.

Like so many other aspects of human life, sleep has now become a commodity, which we are desperate to acquire and never quite sure of possessing. Yet the idea of a single block of unbroken sleep is most probably a recent invention. In an influential series of articles and a book At Day’s Close, the historian Roger Ekirch has argued that the basic form of human sleep prior to the mid-19th century was biphasic. Humans would have a first and then a second sleep. Retiring around 9pm or 10pm, they would sleep till midnight or 1am, then rise for an hour or two – a period known as “watching” – then return to their “second sleep” till morning. Although the times for starting the first and second sleeps would shift historically and geographically, the biphasic pattern was more or less constant.

Different cultures and times would have different ways of understanding this division of sleeps, just as the activities to fill the gap between the two sleeps would vary. These might involve having sex, needlework, cooking, reflecting on dreams and a number of other interstitial practices. But from culture to culture, from region to region, versions of this distinction between “first” and “second” sleep would invariably appear, and the terms have now been found in about 30 languages.

By the mid-1800s, references to the two sleeps were on the wane and consolidated sleep was becoming the norm. Ekirch at first linked this to the rise of artificial lighting, as gas and then electrical lighting were to replace the oil lamps that had appeared on city streets in the 17th century. Artificial lighting opened up new possibilities, and encouraged and facilitated later bedtimes. He would add social and economic dimensions to his account: changes in how work was understood, the rise of shift work and scheduling, new technologies and their impact on production processes, the concept of time management and notions of a work “ethic” suited to industrial capitalism all helped create the model of consolidated sleep. For Ekirch, it seemed clear that an original biological process was being warped by human social change.

Today there is some controversy over these claims, but interrupted sleep was clearly far less of a problem in the past than it is now, with medical and lay texts focusing more on difficulties in falling asleep than on night-time waking until relatively recently. When we wake at night, should we take comfort in the fact that biphasic sleep has for centuries been the rule and not the exception, waiting out our “watching” hour until we are lulled back into sleep?

Drug companies tell people that they may require medication if they aren’t getting their sleep hours. Photograph: Josette Taylor/EyeEm/Getty Images

Well we could try, but we’d be up against the relentless barrage of sleep hygiene that warns of an early grave if we don’t sleep through. How are we supposed to navigate a broken night once we learn that sleep will protect us from cancer and dementia, lower the risk of heart disease, stroke and diabetes, and make us happier, less anxious and less depressed? Won’t the fear of not achieving our eight hours then have a dramatic effect on sleep itself? Individual variability and changes of sleeping habit are now often depicted as hazards, with “Science” continually invoked to tell us what is right and what is wrong with our efforts.

Just as we are both evaluated and pushed to self-evaluate in so many other areas of life, so now sleep itself becomes the first point of our daily review. We wake up not simply to worry about the tasks of the day but, first of all, to assess whether we have had our required hours and then, inevitably, worry about the consequences of our failure. A few decades ago, variety shows on Saturday night would showcase performers singing and dancing, but today we also get a panel of judges evaluating. How long would it be, indeed, before this merciless culture of evaluation came to colonise other aspects of our lives, including sleep?

The new sleep books capitalise here on our sense of guilt. As we lie awake at night, thoughts tend so often to cluster around what we haven’t done, have failed to do or left unfinished. Sins of omission become magnified, just as neglecting to brush one’s teeth, wash or remove makeup can strangely come to seem like catastrophes. The period before sleep was for centuries seen as a time of spiritual purification, with sins repented before bed. Sleep could then follow as a reward for Christian behaviour, highlighting the link between sleep and conscience. Yet when we lie down, our daily sins become amplified. The unfinished business of the day that keeps us awake acts as a perfect magnet for deeper issues of conscience and guilt. A debt of love, for example, that cannot be paid, an acknowledgment or a reproach never voiced. Insisting on perfect sleep and turning it into a task to be performed is yet more fuel to this failure. It’s true that broken sleep might be bad for our health, but the insistence on achieving an unattainable ideal of sleep might also be harmful. No one is measuring what it feels like to strive for a sleep that escapes us, or factors in the effects of the resulting sense of failure.

No one is measuring what it feels like to strive for a sleep that escapes us, or the resulting sense of failure

It is illuminating here to compare the popular sleep books of the 1960s and 70s with those of today. On the first page of his seminal 1978 study The Sleeping Pill Ernest Hartmann writes: “To a certain extent life is pain and sorrow”; by 2017 Matthew Walker’s Why We Sleep presents homo sapiens as a kind of champion among animals, whose sleep gives us unique powers of rationality and creativity. Rapid eye movement sleep helped modern humans’ “rapid evolutionary rise to power” and constitute a “globally dominant social superclass”. “Sleep,” observes Walker, “recalibrates our emotional brain circuits, allowing us to navigate next day social and psychological challenges with cold-headed composure” so that we attain a “level-headed ability to read the social world around us”.

Whereas in Gay Gaer Luce and Julius Segal’s bestselling 1969 study Insomnia, the opening sentence reads: “There is only one sure way to escape insomnia … not to be born”, in the new sleep literature there is no place for human fracture and dislocation. We can read today that sleep helped us to become “emotionally astute, stable, highly bonded and intensely social communities of humans”, a diagnosis that many of us might find at odds with what we see on the news every day or learn from world history. How could the pendulum have swung so acutely from a realistic view of the complexities of human life to the sort of fantasy world described by today’s sleep hygienists?

With the aspiration to become “well-slept individuals”, we see a wholesale redrafting of social problems as individual ones. What the new sleep literature is bringing about is a massive depoliticisation of sleep. In the 1980s, Thatcherism aimed to atomise social issues into personal ones, so that being unemployed was transformed into failing to find a job. Social inequalities and deprivation were presented as individual failures, thus shifting responsibility from government and its agencies to the psyche itself. This chimed with the rise of the new clinical category of depression. The media was filled in the 90s with stories about depression: how not having enough serotonin will make one depressed, how detrimental this is for our health, and how much the economy loses through depressed workers. This time around the culprit is not depression but sleep deprivation. Anxiety, sadness and failure are now presented as the consequence of a lack of nourishing sleep. Rather than seeing insomnia as the result of a depressive state, causality is inverted: we are depressed because we haven’t slept.

Walker divides human life into different classes, claiming that the brains of those who sleep well display rationality while those who sleep badly will be irrational and even deviant. Underslept workers, he tells us, are not only less productive, they are also “more unethical”, more likely to be “deviant and more likely to lie”, blaming others for their errors and taking credit for other people’s work. He divides people, accordingly, into the “normal” and the “socially abnormal”.

The cross section of one mattress. Adverts for mattresses have become commonplace, while the sleep industry has grown to an estimated $76bn a year. Photograph: Zoonar GmbH/Alamy Stock Photo/Alamy Stock Photo

Yet the descriptions given of the sleep-deprived individual in fact apply to most people today in urban society. Rather than recognising the effects of socioeconomic burdens and internal pain, human difficulties are redefined through the new lens of unbroken sleep. Drug companies take out advertisements to tell people that they may have a sleep disorder and require medication if they aren’t getting their sleep hours, if they are lacking the energy to do the things they need to do, such as spending time with their family or performing their duties at work, or if they experience mental tiredness, body fatigue, low motivation and difficulty concentrating. Yet, as anthropologist Matthew Wolf-Meyer points out, aren’t these symptoms the very conditions of modern life, and indeed, of life as it has been lived for centuries?

This is not to say that we should ignore our sleep problems. But we should be more aware of how social forces shape our understanding of sleep. Science has not solved all of sleep’s mysteries, and many of the grand claims to be found in today’s literature should be treated with caution. Factual errors (about REM and non-rapid eye movement sleep) and misrepresentations (about the properties of melatonin, adenosine or cortisol) are rife, and speculative hypotheses are presented as hard facts.

Take the idea of a kind of nightly natural selection. According to this theory, while we sleep, our brain is busy with the task of “culling” unnecessary information and “enhancing” the retention of what we need. Walker even advocates memory deletion, telling us that his hope is “to develop accurate methods for selectively weakening or erasing certain memories from an individual’s memory library when there is a confirmed clinical need”. This sort of behavioural hygiene is of course the stuff of innumerable Orwellian fictions. It is probably not an accident that the idea of deleting people’s memories has been ubiquitous in the darkest visions of the future, and it raises the question, of course, as to who might confirm the “clinical need”: the patient, the doctor, or the state?

The sleep industry needs a reality check here. Although many of us have our own individual problems with sleeping, this should not act as an excuse to move attention away from our political landscape. In a world of massive job insecurity, long commutes, economic precarity and the pressure to maintain a positive image, how well can we really be expected to sleep? Should we be blaming ourselves and our mattresses, allowing ourselves to be duped in this latest chapter of marketing the human condition?

Insomnia is, of course, an agonising state, but its realities should be acknowledged and unravelled with the complexity that they require. Gayle Green’s brilliant and acerbic 2008 book Insomniac describes not only her exploration of sleep research but also her many less than successful attempts at treatments and therapies. Her candid, funny and even-handed approach is a perfect antidote to the new sleep hygiene, and may be far more helpful to those who struggle with sleep.

“Sleep is the most innocent creature,” Kafka wrote, “and sleepless man the most guilty.” When sleep experts take payments from banks and large corporations to give seminars to their executives on how to sleep soundly, we might wonder about their more lowly employees and the outsourced labour that sustain the company’s growth. There has always been an association, through literature, religion and psychology, between sleep and conscience. The irony here is that as the world unravels around us at so many levels, we are under increasing pressure to achieve a solid eight hours. This is ideology at its purest, and we should get woke to new sleep hygiene and the agendas that it carries.

• Why Can’t We Sleep? by Darian Leader (Penguin Books, £6.99). To order a copy go to guardianbookshop.com. Free UK p&p on all online orders over £15.



