The longer a teenager spends looking at a screen throughout the day, the worse quality sleep they are likely to have.
The recent findings suggest the need to update recommendations on electronic use and extend them to include tablets and smarthphones, the British Medical Journal (BMJ) reported.
To make their findings, researchers looked at 10,000 16 to 19 year olds from a Norwegian study. The teens provided information on their screen time outside of school, including "electronic devices: computer; smartphone; Mp3 player; tablet; games console; and TV," the researchers reported. The study subjects were also asked about their sleep routines on both weekdays and weekends.
Almost all of teens admitted to using some form of electronic within one hour of going to bed. Using any electronic device throughout the day and right before bed was linked to an increased risk of taking longer than an hour to fall asleep. Total daytime screen use of four hours or more was linked to a 49 percent increased risk of taking more than 60 minutes to get to sleep, and two hours of screen time was linked to longer sleep onset latency and shorter sleep durations.
Computers were found to be the biggest culprit in sleep loss, even though they were the most commonly-used device. Those who used multiple devices were found to be more likely to have sleep troubles than those who only used one, and teens who used four or more electronic devices were 26 percent more likely to take longer than an hour to fall asleep than those who only used one. Teens who used two or three devices were 50 percent higher to sleep for less than five hours compared to those who only used one, and those who used four or more were 75 percent more likely to sleep for this duration.
"The recommendations for healthy media use given to parents and adolescents need updating, and age specific guidelines regarding the quantity and timing of electronic media use should be developed," the researchers wrote. "The current recommendation is not to have a TV in the bedroom. It seems, however, that there may be other electronic devices exerting the same negative influence on sleep, such as PCs and mobile phones. The results confirm recommendations for restricting media use in general."
The findings were published in a recent edition of BMJ.
