Published Jun 18, 2010 at 4:30 PM EDT Updated Jun 21, 2010 at 12:17 PM EDT How much sleep is enough? Is how sleepy you feel a good judge of whether or not you are getting enough sleep? If you get less sleep than some ideal amount but you feel fine, could you be damaging your health anyway? Are we getting less than we used to? Recent research provides some surprising answers. Adults typically need
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