For most of human evolution, our sleep patterns have revolved around the pattern of the sun.
Then our circadian rhythms were altered with the discovery of fire, and changed forever when we discovered electricity.
Now we can keep the lights on and a glowing screen in front of our faces whenever we want.
The difficult part, sleep experts are finding out, is rediscovering how to turn it all off.
A common complaint for modern parents is how much time their kids want to spend on their devices, whether it be their phones, tablets, or computers.
Besides fears that they’ll miss the world around them, many parents are concerned about the long-term effects of too much screen use.
A new study suggests that it’s not just the screens but the particular hue of the blue glow they admit.
New research out of the Netherlands suggests that cutting off screen time two hours before it’s time to call it a night — or at least wearing glasses that block the blue hue — could make significant differences in a young adult’s sleep patterns.
The research was presented last weekend at the annual meeting of the European Society of Endocrinology in Lyon, France.
The findings haven’t been published yet in a peer-reviewed journal.
To test the effects that blue-light emitting screens had on young people, researchers recruited 55 Dutch children ages 12 to 17 with varying degree of daily screen time usage.
They were divided into three groups. Some were studied while using their screens as normal, while others wore glasses that blocked the screens’ blue light, and others completely abstained from glowing screens.
Their sleep quality was judged over a five-week period using diaries, machines that track when a person is restfully sleeping, and by sampling their levels of melatonin, a hormone associated with sleep.
Researchers say both the blue light-blocking glasses and reducing screen time a few hours before bed equated to overall better sleep.
One of the head researchers, Dr. Dirk Jan Stenvers, a postdoctoral research fellow and clinical endocrinology fellow at the Amsterdam UMC, said the data shows that complaints of sleep problems, including taking longer to get to sleep, are due in part to the blue light emitted by screens.
“Adolescents increasingly spend more time on devices with screens, and sleep complaints are frequent in this age group,” Stenvers said in a statement. “Here we show very simply that these sleep complaints can be easily reversed by minimizing evening screen use or exposure to blue light.”
The study offers practical insight for parents who are helping their children get meaningful rest.
Dr. Gina Posner, a pediatrician at MemorialCare Orange Coast Medical Center in Fountain Valley, California, told Healthline that one of the interesting things she found in the study was the use of blue light-filtering glasses.
“This is great for my patients that refuse to reduce their screen time, but I still believe it is important to keep it to a maximum of two hours a day to increase physical activity as well as allow children time [to] decompress before bedtime,” Posner said.
Dr. Danelle Fisher, vice chair of pediatrics at Providence Saint John’s Health Center in Santa Monica, California, says when discussing “sleep hygiene” with families, it’s important to note that less screen exposure before bedtime helps kids fall into a restful sleep faster.
“Sleep is important in this age group and more and more adolescents are experiencing sleep disturbances,” Dr. Fisher said. “This can give families insight into the problems adolescents can experience with sleeping and how to improve sleep quality by trying to minimize screen exposure.”
Experts say it’s especially important because not getting enough sleep doesn’t just equate to being tired and having trouble concentrating.
In the long run, it can lead to preventable diseases, such as obesity, diabetes, and heart disease.
With the new research, Stenvers and his fellow researchers say they’re interested in whether reduced screen time and improved sleep has longer lasting effects. And whether the research translates to adults.
“If we can introduce simple measures now to tackle this issue, we can avoid greater health problems in years to come,” he said.