Going to bed earlier protects teenagers against depression and suicidal thoughts.
Of 15,500 teens studied, those who went to bed after midnight were 24 percent more likely to have depression than those who went before 10 o’clock. And those who slept fewer than five hours a night had a 71 percent higher risk of depression than those who slept eight hours.
As well as the higher risk of depression, night-owls were 20 percent more likely to think about suicide. Those who had less than five hours sleep a night had a 48 percent higher risk of suicidal thoughts compared with those who had eight hours of sleep.
Teenagers who reported they "usually get enough sleep" were 65 percent less likely to be depressed.