World Sleep Day: The eight-hour sleep myth and why you’re getting bedtime all wrong

It was a curious sight: five or six glassy-eyed people staring back from the laptop screen, yawning in tandem on a Zoom call each week, learning how to sleep. The course of group cognitive behavioural therapy (CBT) had been prescribed by an NHS consultant in an attempt to fix a recurring issue – long, arduous months spent sleepless, a ghost in my own house, sulking around in the small hours. I’d been optimistic that the class would be the key to finally mastering this basic, human skill. Sadly it was not, though to be fair I did find myself struggling to stay awake during the two-hour sessions spent staring at clipart on decades-old slideshows.

I’d first gone to the GP in April 2022, after four months of averaging about three hours of sleep per night, mostly between the hours of 5am and 8am. I’d never been the sort of person who could stand a “bedtime”. When the world had gone to sleep I cheated time, or so I thought, writing and reading after hours until I dropped off at a reasonable time of about 1am. I’d been happy in my nights spent in the twilight.

Then something changed. Slowly the nights got longer – at first sleep came at 2am, soon after, 3am and 4am – and the gentle quiet that I’d always found to feel safe, away from the pressures of the day instead became bleak and solitary. Suddenly the hours that I had filled with ideas were loaded up with questions instead. How will I cope tomorrow? When will I finally feel tired? Why can’t I just sleep?

I’m no stranger to insomnia – I’d even been prescribed sleeping pills as a child, though they had no effect. I spent my days trying to find reasons and solutions for my lack of shut-eye at night: the winter, lack of exercise, Dry January, stress. I joined the gym and began doing pilates four times a week to wear myself out. I still laid awake at night, only with slightly better abs.

I started a night-time routine – skincare, all the rest of it – got an eye mask, banned screens, caffeine and carbs, wrote down nagging anxieties to put them to bed first, got up, read, reluctantly meditated and snapped at anyone who mentioned “sleep hygiene”. None of it helped and now, I discover, could have all been making it all worse.

In How To Sleep Like a Caveman: Ancient Wisdom for a Better Night’s Rest, Dr Merijn van de Laar makes a compelling case for the one-third of adults worldwide who struggle with insomnia. Throw the “sleep hygiene” rules out of the window, he says – we need to change how we think about the eight-hour rule and rest in general.

“The evolutionary theories around sleep are amazing, because not many people know about them,” Van de Laar explains. “It’s very important to go back to the body – how the body is made and what we're actually intended to do. The last couple of hundred years have seen such a rush into new technologies and into new science, but we still have those old bodies.

“And to really understand something as ancient as sleep, you have to go back to the roots of it all.”

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The book, which has now been released in 20 countries to wide acclaim, came about via Van de Laar’s long career and extensive research into how we sleep. Having studied behavioural psychology and completed a PhD in sleep, he has spent his life deciphering the best conditions for rest and, crucially, gently skewering the advice that inadvertently keeps us awake at night.

Like, for instance, the idea that we need eight solid hours of sleep per night, every night, or that waking in the night for a couple of hours is an innately bad thing. Actually, widely reported research has long disputed the idea that eight hours is key to wellbeing – rather, says Van de Laar, that it varies from person to person. And if we take a lead from our ancestors’ behaviour, being awake for parts of the night is pretty normal.

“We know from studies in the Hadza tribe in Tanzania – who still live in the same circumstances as we did hundreds of thousands of years ago – that lying awake is something they do a lot. On average, they lie awake more than two hours per night.” The key difference, he says, is “they don’t stress about it”.

“Waking during the night really has a function in the tribe – it’s important for survival … population data also tells us that seven hours’ sleep is the average, but that’s including being awake for up to 20 per cent of each night. A lot of people don’t know that, and are then faced with this perfect picture of sleeping eight hours without interruptions, which poses a lot of tension for people with insomnia.”

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Even those who have never suffered with long-term insomnia will know the infuriating cycle of clock-watching and internal panic during restless nights – and subsequently all the conflicting advice on what to do about it.

When I took part in group sleep CBT therapy, we were given different techniques to try. Using the “15-minute rule”, wherein if we were not asleep within 15 minutes of getting into bed, we should get up, go to another room and find “enjoyable things to do” (suggestions were “doing a puzzle, knitting, colouring books etc”) until we were sleepy, and to repeat the cycle as many times as possible. I played the piano for about three hours one night. I didn’t sleep.

Other techniques included banning yourself from shutting your eyes, using timelines and formulae to find a “buffer zone” between the day and bedtime and setting a strict “latest rising time”. We were asked to meticulously document our sleep on an Excel spreadsheet (grim) and work out our average sleep time using a calculator or conversion chart.

After the first week, I gave up filling it in, easily overwhelmed by exhaustion, and resigned myself to never sleeping again.

Crucially we were told to “reduce stress”. Easier said than done in a modern world, which is far from the environment cavemen slept peacefully in. Again, Van de Laar says that being stressed out naturally puts more pressure on us to sleep, in order to compensate for the worry.

“It’s then very natural and logical for your body to tend to wake more during the night, because if there’s impending danger, you want to know about it and check your environment is safe. So adjusting your expectations of how much sleep you might get – rather than becoming more frustrated that you failed to get this perfect eight hours – is very important.”

This idea – that we must put in more effort to perfect a good night’s sleep – is a myth that Van de Laar is keen to dispel.

“If you ask a person who sleeps well, ‘How do you sleep well?’ the person answers, I don't know, I just go into my bed and I fall asleep. If you ask a person with insomnia, ‘what do you do to sleep?’ they’re like, I bought a ?5000 mattress, I stopped using coffee during the evening, all manner of things,” he observes.

“I’ve trained between 5,000 and 6,000 people with insomnia – and I suffered from insomnia myself – and from all the cases I’ve seen most people were actually obsessed with good sleep. Actually, people with insomnia should sometimes do less to sleep better.”

Van de Laar also notes that rather than there being a “correct” circadian rhythm, each person is likely different to the next. The only thing you need to know is what works for you, and “respect your natural biorhythm” – the body’s natural cycles – he says, especially if you suffer from complex mental illness, where changes in sleep are the biggest precursor to an episode.

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The idea that being an early riser is better is also problematic – in caveman days, it was useful to have people up at various different hours. Van de Laar explains, “I believe the differences in biorhythm are there for their evolutionary purpose. The essence of different prototypes have helped us to survive during the night.”

Katherine May, the author of the bestseller Wintering: The power of rest and retreat in difficult times, wrote in The Independent last year about how historian A Roger Ekirch found evidence of this midwinter break in sleep across history. Waking up in the middle of the night was seen as a valuable quiet time, when people talked, had sex, prayed, and even socialised with neighbours. It was only after the arrival of artificial light, she pointed out, that we lost this secret corner of our lives.

Getting natural daylight as soon as you can in the morning stops the production of melatonin, our sleep hormone, that helps get you in sync with your natural biorhythm. Exercising – even just walking a bit more – in the daytime is also useful, which isn’t a surprise. If you’re trying to get better sleep, Van de Laar says, spend less time in bed, not more.

The CBT didn’t work for me but everyone has to find their own path; it may well work for others. Now, rather than listening to the noise around the search for the perfect night’s sleep, the rule book is being thrown out. On the sleepless nights that will inevitably return at some point as they always do, I’m going to try a new method: doing nothing. It might not be reinventing the wheel but it might well do my sleep cycles – and yours – some good.

How To Sleep Like a Caveman by Merijn van de Laar is out now (William Collins, ?20)