(BBC) — Poor sleep in teenage years could be an early warning sign for alcohol problems, illicit drug use and "regretful" sexual behaviour, research suggests.
US scientists found adolescents with bad sleep habits were more likely to engage in risky behaviour in the years to come than those who slept soundly.
They say parents should pay closer attention to teens' sleep schedules.
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Other research suggests a good night's sleep is key to making good judgements.