More than 3 in 4 high schoolers have given short shrift to sleep in recent years, which could make it harder for schools to help them recover academically and emotionally from the disruption of the pandemic.
That’s the conclusion of new research from the federal Centers for Disease Control and Prevention. It found students who averaged fewer than seven hours of sleep on school nights had much higher risk of difficulty with school work and more mental health problems than teenagers who regularly got sufficient sleep, generally defined as at least eight hours.
CDC researchers led by Sarah Sliwa and Shannon Michael tracked data on adolescents’ sleep habits in the nationally representative Adolescent Behaviors and Experiences Survey from January to June 2021.
The American Academy of Sleep Medicine recommends teenagers ages 13 to 18 get at least eight to 10 hours of sleep per night, but the researchers found more than 76 percent of students in that age group averaged four to seven hours of sleep a night.
While adolescents often cite homework or study sessions as among their top reasons for staying up late, the results suggests schools and families should help students learn to plan their schedules and sleep routines better.
“While [time management] is a struggle, the findings of this study underscore the importance of sleep,” said study co-author Michael. “Students who slept less than 7 hours during an average school night were more likely to report greater difficulty doing schoolwork and poor mental health.”
While just over 37 percent of adolescents overall reported mental health problems during the study period, more than 55 percent of students who slept four hours or less a night and about 49 percent of students who got five hours of sleep on school nights were identified with mental health problems, which could include anxiety, depression or other issues. By contrast, only about 25 percent of teenagers who got eight hours of sleep or more on school nights reported mental health challenges.
Separate studies find that a student’s sleep hygiene—such as whether they go to sleep at a consistent time each night, get the recommended hours of nightly sleep, and avoid devices that can interfere with sleep quality—accounted for as much as 25 percent of the difference in how students perform on tests and quizzes over the course of a semester.
While the CDC study looked only at the overall amount students sleep, not the quality or schedules, prior studies have found adolescents have experienced more late-night screen time and worsening sleep hygiene in the last decade. And even before the pandemic, teenagers were twice as likely to go to sleep with digital devices like cellphones or laptops that can interfere with their bodies’ sleep hormones.
“Later school start times and information to families about good sleep habits and parent-set bedtimes might help support both learning and mental health,” Michael said.
Separately, the CDC has even encouraged high schools to make time for chronically sleep-deprived students to take afternoon naps.