Teens who don't get enough sleep may be more likely to smoke, drink, get into a fight and show other risky behaviours compared with those who are better rested, researchers have found.

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High school students who got insufficient sleep were more likely to smoke and show other risky behaviour. ((Marco Di Lauro/Getty))

Almost 70 per cent of high school students get insufficient sleep, defined as less than eight hours on school nights, according to the U.S. Centers for Disease Control and Prevention's study. 

The agency surveyed more than 12,000 high school students to look at associations between lack of sleep and 10 behaviours:

  • Drinking soda or pop one or more times per day (not including diet soda or diet pop).
  • Not participating in 60 minutes of physical activity on five or more of the past seven days.
  • Using computers three or more hours each day.
  • Engaging in a physical fight one or more times.
  • Cigarette use.
  • Alcohol use.
  • Marijuana use.
  • Sexually active.
  • Feeling sad or hopeless.
  • Seriously considering suicide.

"Many adolescents are not getting the recommended hours of sleep they need on school nights," said study author Lela McKnight-Eily, of the CDC's division of adult and community health in Atlanta.

"Public health intervention is greatly needed, and the consideration of delayed school start times may hold promise as one effective step in a comprehensive approach to address this problem," she added in a release.

The research was released online this week in advance of print publication in the journal Preventive Medicine.