Such people do exist, of course. The late British Prime Minister Margaret Thatcher, for example, was famous for operating on a few hours' sleep. Some entrepreneurs and Wall Street traders seem to follow suit.
But if you think you need to do the same thing to get ahead, think again. A growing body of research is finding that, on the contrary, those who get a good night's sleep are usually more productive at work. They think more clearly, quickly and creatively than those trying to get by on a few hours' rest and a gallon of caffeine.
That's because sleep doesn't just rest the brain, say medical specialists. It allows the brain to perform vital maintenance and restoration tasks. Brains that get too little sleep simply cannot perform as well as those that are rested.
"There's no doubt that sleep deprivation affects job performance," says the Detroit Medical Center's Safwan Badr, a former president of the American Academy of Sleep Medicine. "The evidence is compelling that when you do not get enough sleep…you are not as productive."
Charles Czeisler, a sleep specialist at Brigham & Women's Hospital in Boston, agrees. "Missing a night's sleep degrades our neurobehavioral performance"—that is, our mental acuity—"by the equivalent to being legally drunk," he says.
And, he warns, this doesn't only apply if you miss one night's sleep completely; you'll see similar effects if you simply sleep too little each night over time.
For the first time, new research has attempted to put some numbers on the link between more Zzzs and more Benjamins. Matthew Gibson and Jeffrey Shrader, graduate researchers in the economics department of the University of California, San Diego, compared wage data with sleep times recorded in the U.S. Census Bureau's American Time Use Survey. Their conclusion: For those who are sleeping too little, "a one-hour increase in long-run average sleep increases wages by 16%, equivalent to more than a year of schooling."
Adults need eight hours of sleep on average, experts say. There is some variation between individuals, but it is far less than many think. Many of those who think they can be just as productive with a lot less are fooling themselves, he says. In round numbers, the percentage of adults who can really get by on five hours or less per night "is about zero," says Dr. Czeisler.
It's easy to be fooled. Research suggests that tired professionals are still able to go through the motions of their jobs—such as sitting in meetings, understanding reports, and performing the kinds of routine professional tasks they usually undertake.
Modern corporations often push key employees to go short on sleep, demanding they work longer hours and stay in touch late at night. But sleep loss impairs higher-level brain skills.
When we are tired, we find it much harder to think innovatively and to make creative leaps, say researchers. We find it harder to adapt our thinking to new information or to learn new lessons. We struggle to make good judgments in very ambiguous situations. We are also more vulnerable to mood swings, more irritable and less able to get along with others.
Consider: At England's Loughborough University in 1999, researchers Yvonne Harrison and James Horne tested the effects of sleep deprivation on a small group of healthy young participants. They were given complex business-situation tasks in the form of a game, as well as some critical reading tasks. Those who went short on sleep were able to keep up with the reading, they found. But when it came to the complex game, "their play collapsed," they reported.
'Herd Mentality'
In other words, if you're a white-collar professional, sleep loss may not get you fired. But it may be stopping you from doing the things that would get you a promotion. It may even help explain the "herd mentality" often seen on Wall Street.
Yet even as more of us are working in jobs that require innovative and creative thinking, we are getting less and less sleep.
We get far less sleep than our grandparents, say specialists. Dr. Czeisler says 20% to 30% of workers sleep less than six hours a night during the week. Fifty years ago, he says, the number was around 2% to 3%.
Experts blame electric lights, alarm clocks, and now the Internet and smartphones.
"If you need an alarm clock to wake you up, by definition, you're not getting enough sleep," warns Dr. Czeisler. Some patients tell him they keep their smartphones by their bedside table so they can check emails last thing at night, first thing in the morning, and in the middle of the night if they wake up.
His verdict: "It's insane."
From: The Wall Street Journal