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When You Don't Snooze, You Lose

Reveals the effect of sleep deprivation. Importance of daytime
alertness; Suggested concepts for a sleep-smart lifestyle.


For all the fascination sleep holds---why do we do it? what do dreams mean?--a top snooze expert insists that the most important thing about our nightly repose is that we get it.

"Out of the vast ocean of knowledge about sleep," writes William Dement, M.D., Ph.D., in his new book, The Promise of Sleep (Delacorte, 1999), "nothing is more Important than the topic of sleep debt." Not only is sleep deprivation the likely cause of the Exxon Valdez oil spill, he says, but being drowsy during the day also leads to car accidents and work tragedies, not to mention a general loss of reasoning and thinking ability: "Daytime alertness is the number one determinant of mental functions." A longtime researcher in the field of sleep, Dement found in 1988 that of a group of people who said daytime sleepiness was no problem, only I in 10 was optimally alert. Furthermore, a 1997 study by the National Sleep Foundation found that at least 75% of adults feel drowsy during the day. Dement has even deemed the lack of concern about sleep deprivation a national emergency.

How to adopt what he calls a sleep-smart lifestyle? Three concepts to remember: First, people should try to maximize their sleep efficiency. People who are sleep-deprived fall asleep instantly, while well-rested folks take longer to fall asleep and wake more during the night, so they are in bed for longer. Just as an extreme lack of sleep may be counterproductive, so is too much. Second, pay attention to what times of day you're naturally more alert and when you tend to slump, and shift your work and sleep schedule accordingly. Finally, don't feel guilty about sleeping late, if that's what your body needs. "Sleep quotas are biologically fixed," says Dement. "Some people need 10 hours of nightly sleep like their shoe is a size 10."

PHOTO (COLOR): "Out of the vast ocean of knowledge about sleep"