Is your teen having trouble sleeping? It could be the smartphone.
Experts say teenagers need a minimum of nine hours’ sleep to be engaged and productive. But two long-term national surveys of more than 360,000 teenagers found that four out of ten teenagers slept less than seven hours a night.
That’s 58 percent more than in 1991 and 17 percent more than 2009, when smartphone use became mainstream, researchers say.
And the more time they spend online, the less sleep they get, according to a study published Oct. 19 in the medical journal Sleep Medicine. Students online for five hours a day were 50 percent more likely to be sleep-deprived than those who were only online one hour a day.
Why is this? Researchers say the light from smartphones and tables disrupts the natural sleep-wake cycle.
“Our body is going to try to meet its sleep needs, which means sleep is going to interfere or shove its nose in other spheres of our lives,” said study co-author Zlatan Krizan, associate professor of psychology at Iowa State University.
Study leader Jean Twenge, a psychology professor at San Diego State University, said everyone — young and old — should limit use to two hours a day.
Or at least try to limit it at night. “Given the importance of sleep for both physical and mental health, both teens and adults should consider whether smartphone use is interfering with their sleep,” Twenge said. “It’s particularly important not to use screen devices right before bed, as they might interfere with falling asleep.”
That applies to adults, as well. Another study conducted by a mobile security company found 63 percent of women and 73 percent of men between ages 18 and 34 can’t go one hour without checking their phones.
But that constant connectivity can actually make you less productive at work and less satisfied with your personal life, according to research being done at Harvard. A survey on “Stress in America” published by the American Psychological Association found that 44 percent of the people who check email, texts and social media “often” or “constantly” said they feel disconnected from family, even when they’re together.
Unplugging means taking regular breaks from devices and limiting your availability, which the experts say will help you relax, reflect and be more creative. Thus was born the “National Day of Unplugging,” calling for everyone to let go of the phone on the first Friday in March.