Bad sleeping patterns are practically hardwired into teenagers. Nevertheless, while lie-ins and late nights are hardly new phenomena in the world of teens, it's becoming evident that one element of 21st-century life is screwing with their circadian rhythms. 

Just as previous studies have shown, the blue glow of smartphones and laptops could play a role in disrupting our natural sleeping patterns, especially in teenagers. Furthermore, new research argues that teens can help remedy their sleeping problems, as well as improve their concentration and mood, just by cutting their exposure to light-emitting screens in the evening.

This could simply be achieved by avoiding the devices in the evening. Alternatively, if that seems like an unlikely pipedream, you can also get these results by wearing glasses that block out blue wavelengths of light.

Presenting their preliminary findings at the European Society of Endocrinology Annual Meeting 2019 over the past few days, scientists from Amsterdam University Medical Centre showed that teenagers who had more than 4 hours per day of screen time had on average 30 minutes later sleep onset and wake up times compared to those who had less than 1 hour of screen time per day.

They went on to carry out a randomized controlled trial on 25 frequent users to see whether blocking the screen’s blue light with glasses or having no screen time at all during the evening had any effect on sleeping patterns. Their results showed that the glasses and screen abstinence both resulted in the teenagers falling asleep 20 minutes earlier. They also started to reap the benefits of this sleep, such as better concentration, less fatigue during the day, and boosted mood.

"Adolescents increasingly spend more time on devices with screens and sleep complaints are frequent in this age group. Here we show very simply that these sleep complaints can be easily reversed by minimizing evening screen use or exposure to blue light,” Dr Dirk Jan Stenvers, from the Department of Endocrinology and Metabolism of the Amsterdam UMC, said in a statement.

It’s worth noting that these results have not yet been published or peer-viewed. Independent experts in the field have praised the preliminary findings as “interesting” and “certainly promising," but they also warned that further research needs to be carried out before they consolidate their conclusions. 

"One caveat is that the study did not include an active control condition (e.g. wearing another type of glasses), therefore adolescents’ expectations may have contributed to the results," commented Dr Iroise Dumontheil, reader of Cognitive Neuroscience at Birkbeck, University of London, who was not involved with the study. 

The issue of technology and sleep has been a hot topic in recent years and, as such, it’s also garnered a fair amount of scientific research. Blue light has the power to mess with our circadian rhythm because it suppresses the release of melatonin, a hormone that regulates the human body's sleep-wake cycle. In days before artificial lighting and buzzing smartphones, this was a pretty helpful means of helping us wake up as the Sun rises and keep our brains alert during daylight hours. But now, in a world filled with glowing screens, these biological signals can become fuzzy and out of sync. 

However, as this study demonstrates, it’s not too difficult to overcome these troubles, either by avoiding screens in the evening or wearing blue-blocking glasses. Alternatively, many smartphones and apps offer a night mode that filters out some the blue/green wavelengths at night.