Screen use both day and night worsens teens' sleep
A new study of 10,000 teenagers in Norway found that the more they used electronic devices, such as smartphones and tablets, the less quality sleep they got.
Participants answered questions about how frequently they used electronic devices outside of school and their sleep patterns on the weekdays and weekends. Many participants said they got fewer than five hours of sleep per night. Girls spent an average of five and a half hours per day in front of a screen, while boys spent an average of six and a half hours per day looking at their smartphones or tablets. Girls spent more time chatting online and boys spent more time playing video games.
The results showed that screen time directly before bedtime generally disrupted sleep, but even screen time after school seemed to affect how they slept. Teens who spent more than four hours per day in front of the screen were found to have a 49 percent increased risk of not falling asleep within an hour of going to bed. Those teens tended to get fewer than five hours of sleep per night.
The researchers made note of previous research that has suggested that staring at an illuminated screen before bedtime can affect a person's natural body clock.