Judging from recent surveys,most experts in sleep behavior agree that there is virtually an epidemic of sleepiness in the nation. I cantthink of a single study that hasnt found Americans getting less sleep thanthey ought to, says Dr. David. Even people who think they are sleeping enoughwould probably be better off with more rest.
The beginning of our sleep-deficit crisis can betraced to the invention of the light bulb a century ago. From diary entries andother personal accounts from the 18th and 19th centuries, sleep scientists havereached the conclusion that the average person used to sleep about 9.5 hours anight. The best sleep habits once were forced on us, when we had nothing to doin the evening down on the farm, and it was dark. By the 1950s and 1960s, thatsleep schedule had been reduced dramatically, to between 7.5 and eight hours,and most people had to wake to an alarm clock. People cheat on their sleep,and they dont even realize theyre doing it, says Dr. David. They thinktheyre okay because they can get by on 6.5hours, when they really need 7.5, eight or even more to feel ideallyvigorous.
Perhaps the most merciless robber of sleep,researchers say, is the complexity of the day. Whenever pressures from work,family, friends and community mount, many people consider sleep the leastexpensive item on his programme. In our society, youre considered dynamic ifyou say you only need 5.5 hours sleep. If youve got to get 8.5 hours, peoplethink you lack drive and ambition.
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