"He's a short sleeper,” says Fu. In other words, Black has a series of genetic mutations that enables him to thrive on half the shut-eye most of us need. Back in 2009, Fu was part of a research team that discovered a genetic variation shared by a mother daughter pair who both went to bed past midnight and naturally woke up around 4 a.m. When Fu’s team replicated the mutation on a strain of mice, the rodents suddenly started needing less sleep, too.
Since 2009, Fu's team has found an additional two genes that may contribute to condition. It’s a trait that can run in families. Indeed, Black says his father rarely got more than five hours a night, and he believes his sister is also a short sleeper.
While Fu says that short sleepers may simply sleep more efficiently than the rest of us, that's just speculation. Sleep, for the most part, is still a giant enigma “It’s fascinating," says Fu. “We spend around a fourth to a third of our life asleep, and yet we don't know how it's regulated; we have very little idea about what sleep does for us.”
If you think you’re a 'short sleeper,' you’re probably lying to yourself.
Unfortunately, as of yet, we can't train ourselves to need less sleep.
While Fu dreams of the day she’ll be able to genetically alter her own DNA so she can become a short sleeper, she's accepted that for now, she needs at least seven hours.
The vast majority of us require eight solid hours a night. “Most of the variation in human sleep time is between six and eight hours. Once the sleep time gets above nine or below seven there are problems,” says David Dinges, who heads the Sleep and Chronobiology laboratory at the University of Pennsylvania. In other words, while your optimal sleep time rests on a sliding scale, if you are routinely getting less than six hours a night, there’s a 99 percent chance that you’re chronically fatigued.
After Dr. Fu’s research was published back in 2011, she received calls and emails from individuals who believed that they were short sleepers. Most, it turns out, were simply sleep deprived and either unaware or in denial. They were getting less than six hours of sleep a night, “but they didn't feel good,” says Fu. “They were drinking a lot of coffee, and after awhile they have to catch up on sleep.”
As a culture, sleep deprivation has increasingly become both a status symbol – not having time to sleep means you must be important – as well as evidence of a strong work ethic. This is especially true in the hyper-productive, ultra-competitive fish bowl that is the entrepreneurial community, where a good night’s sleep is often bastardized as a luxury reserved for the lazy. Marissa Mayer (CEO of Yahoo), Jack Dorsey (co-founder of Twitter and CEO of Square), Indra Nooyi (chairman and CEO of PepsiCo), Martha Stewart (chair of Martha Stewart Omnimedia) and Donald Trump (chairman of the Trump Organization) have all said that they average less than six hours of sleep a night. And that may be true. In addition to the extra amount of time, short sleepers, Fu's team has found, share characteristics that prime them for successful careers.
“They are very optimistic, very driven, very happy. A lot of them are very accomplished,” says Fu.
These genetic findings are tantalizing; it's easy to see why Fu received calls for non-short sleepers who nonetheless were convinced they fit the bill. Who wouldn't want 25 percent more productive waking hours?