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.