What 'elite sleepers' can tell us all about the eight hour myth
History is full of high achievers who claimed to need only a few hours sleep a night – from Leonardo da Vinci to Margaret Thatcher to Elon Musk. Now, research into so-called ‘elite sleepers’ – who fall asleep late and wake up early, yet feel perfectly refreshed – is changing the way we sleep, and offering clues for ways to treat diseases such as dementia.
This week, neurologists at the University of California San Francisco (UCSF), reported on 10 years of research sequencing the genomes of ‘familial natural short sleepers’, who represent around 3 per cent of the population. They found they shared genetic mutations which make it possible to sleep less without suffering any negative health consequences.
Such discoveries show that our biological make-up plays a key role in determining how long we need to sleep for. While public health guidelines have traditionally recommended eight hours of sleep per night, some of us may need much more or less in order to maintain a healthy lifestyle.
Russell Foster, professor of circadian neuroscience at the University of Oxford, likes to compare individual sleep patterns to shoe size. “There’s huge variation,” he says. “I think that the myth of the eight hours has actually caused quite a bit of anxiety. In fact, the range for humans can typically go from six hours to ten hours.”
Elite sleepers are right at the shortest end of this range and, intriguingly, UCSF neurologists found that their sleeping pattern also came with a number of common personality characteristics. While too little sleep can cause most of us to experience irritable mood and poor cognitive functioning, such as bad memory recall, elite sleepers appear to be the exact opposite.
The elite sleeper will typically go to bed between 11pm and midnight, and wake up five or six hours later without needing an alarm. Despite sleeping little at night, they will not feel tired during the day or in need of caffeine.
Around 90-95 per cent of the elite sleepers studied have what psychologists would describe as type-A personalities – high on ambition and optimism. Many had exceptional memories, higher pain thresholds than average, and a greater ability to cope with jetlag.
The theory could explain how great minds such as Thomas Edison, Nikola Tesla and Leonardo da Vinci required meagre amounts of shut-eye. Modern examples might include the designer and director Tom Ford, who can reportedly manage on as little as three hours per night. Donald Trump has claimed to need only four or five, while Elon Musk reportedly sleeps for no longer than six hours, due to the demands of running his companies.
However, sleep scientists are keen to point out that elite sleepers represent a tiny fraction of the population.
“Making people feel guilty about their sleep, or having this ‘I only got four hours of sleep last night, how brilliant am I?’ approach, is almost tantamount to irresponsible because we’re all so very different,” says Foster. “The consequences could be really bad.”
Albert Einstein, he points out, reportedly slept for at least 10 hours a night. He says that a healthier way of assessing our own sleep patterns and whether we need more sleep is to look at how long you sleep for without an alarm clock, whether you struggle to wake up in the morning, and if you tend to crave caffeinated drinks or a mid-afternoon nap during the day.
A large body of evidence shows getting sufficient sleep is vital for health, and that too little can impair our memory and make people more prone to all kinds of chronic diseases in mid- to late-life, such as cardiovascular disease, cancer, and metabolic problems.
A study of UK civil servants, known as Whitehall II, has made an association between too little sleep and risk of dementia in later life, possibly because of a slow build-up of toxins. Foster says that scientists have found that even one night of no sleep increases the deposition of a protein called beta amyloid, which is implicated in Alzheimer’s disease, by one or two per cent.
“If you get less than seven hours of sleep per night, even in your 50s and 60s, you have an increased risk of developing dementia in your late 70s,” says Tara Spires-Jones, a professor at the UK Dementia Research Institute at the University of Edinburgh.
However, the unique quirks of elite sleepers may be able to help us with this. One of the most fascinating facets of their biology is that while they sleep for fewer hours, their gene mutations also seem to protect them against cognitive decline in later life. Essentially, they seem to be able to pack in all the recuperation and cleansing that the brain and body need to stay healthy, in less time – in other words, their sleep is high quality and low quantity.
Scientists believe the elite sleeper genes provide resilience against the onset of cognitive decline, and untangling the biology behind them could provide new leads for developing future dementia treatments.
“This is an important avenue for future studies,” says Rosa Sancho, head of research at Alzheimer’s Research UK, “but most of us won’t have one of these efficient sleep genes.”
Five signs you're an elite sleeper
You typically go to bed between 11pm and midnight and wake up five or six hours later without needing an alarm
You never feel tired during the day and in need of caffeine, despite sleeping little at night
You have always been very outgoing, ambitious, optimistic and determined, since childhood
You are very rarely affected by jetlag
You are good at multi-tasking and have a high pain threshold