Sleep myths exploded

Are you a night-owl, living among larks? This NYT article is for you:

At least since Benjamin Franklin included the proverb 'Early to bed and early to rise makes a man healthy, wealthy and wise' in his Poor Richard's Almanac, Americans have looked at sleeping habits as a measure of a person's character. Perhaps because in the agrarian past people had to wake at dawn to get in a full day's work outside, late sleepers have been viewed as a drag on the collective good.

Even today, said Edward J. Stepanski, the director of the Sleep Disorders Service and Research Center at Rush University Medical Center in Chicago, "it's a uniformly negative characteristic to be asleep while everyone else is going about their business."

But before slinking back under the covers in shame, slugabeds of the world should consider: Sleep researchers are casting doubt on the presumed virtue and benefits of waking early, with research showing that the time one wakes up has little bearing on income or success, and that people's sleep cycles are not entirely under their control. Buoyed by the reassessment of their bedtime habits, a few outspoken and well-rested night owls are speaking out against the creep of sleepism...
Whatever the negative associations with sleeping late, scientists say there's good reason to doubt the boasts of the early risers. Dr. Daniel F. Kripke, a sleep researcher at the University of California, San Diego, said that in one study he attached motion sensors to subjects' wrists to determine when they were up and about. While 5 percent of the subjects claimed they were awake before 4 a.m., Dr. Kripke said, the motion sensors suggested none of them were. And while 10 percent reported they were up and at 'em by 5 a.m., only 5 percent were out of bed.

Dr. Stepanski said the same is true of people who boast they need little sleep. In a study in which subjects claimed they could get by on just five hours' sleep, he said, researchers found the subjects were sneaking in long naps and sleeping in on weekends to make up for lost z's.

"There's a tendency to generalize and to do it in a self-serving way," Dr. Stepanski said. "If your view is that you can get by on less sleep than the average person, then you're going to play that up."

Scientists call early risers larks, and late sleepers owls, and speak of morningness and eveningness to describe their differing circadian rhythms. Researchers believe that about 10 percent of the population are extreme larks, 10 percent are extreme owls and the remaining 80 percent are somewhere in between. And they say the most important factor in determining to which group a person belongs is not ambition, but DNA.

"Timing of sleep is genetically determined, whether you're an owl or lark," said Dr. Mark Mahowald, the medical director of the Minnesota Regional Sleep Disorders Center. While most people are a little bit owl or a little bit lark, for others, Dr. Mahowald said, altering sleep habits is "like changing your height or eye color."

Addendum: Dr. Michael Rack is back with a new blog, Sleepdoctor...coming soon to my blogroll!