Teenagers who go to bed early are more cheerful than ones who stay up late. Researchers from Columbia University Medical Center in New York studied data from 15,659 adolescents gleaned from the National Longitudinal Study of Adolescent Health which took place between 1994 and 1996. Those children who had a set bedtime of midnight or later were 24% more likely to suffer from depression and 20% more likely to have suicidal thoughts than those who had set bedtimes of 10 p.m. or earlier. Teenagers who slept for five or fewer hours per night were 71% more likely to suffer from depression and 48% more likely to think of committing suicide than those who said they got eight hours a night. Those who said they usually got enough sleep were significantly less likely to suffer from depression or suicidal thoughts. Perhaps the most surprising result of the survey is that 70% of the adolescents said that they complied with the bed times set by their parents. On average there was only a five minute difference between the teenagers' 'official' bed times and when they actually went to bed.
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