6 Hours of Sleep Not Enough Say Scientists

Scientists have good and bad news for hard-driving people who boast they need only six hours of sleep a night. The good news is a few may be right: Researchers at the University of California-San Francisco have identified a family with a genetic mutation that causes members to require only six hours sleep a night. The bad news? The gene is vanishingly rare in humans, found in less than 3% of people.

So almost everyone who says he needs only six hours' sleep is kidding himself. And the consequences of chronic sleep deprivation are serious, says Clete Kushida, president of the American Academy of Sleep Medicine and director of Stanford University's Sleep Medicine Center. Sleep deprivation has been linked to an increase in motor vehicle accidents, deficiencies in short-term memory, focus and attention. It's also tied to depressed mood and a decrease in the ability to control appetite.