It is often thought that the blue light emitted by the screens of electronic devices can disrupt your sleep. Indeed, blue light can suppress melatonin, which is responsible for making you sleepy. Less melatonin means it’s harder to fall asleep and stay asleep. When you have a busy schedule the next day, filled with important work, household errands and meetings, you definitely want to get as much sleep as you can. Previously, this meant you had to avoid blue light before bed. But is this always the case?
Scientific studies strive to answer this question precisely. One study decided to look at previous research done as a whole and compare the data to see if all the results were consistent that blue light before bed would lead to poor sleep. Instead, they found that previous research results were inconsistent. Using your phone before bed doesn’t necessarily mean you won’t sleep well.
Another study looked at sleep from a different perspective. It took into account not only blue light, but also the use of technology in general. Were people watching a movie before bed or arguing with strangers on social media? This study found that mental and emotional stressors related to technology use may be a better indicator if you’re having trouble sleeping, not just blue light itself.
Blue light results are inconsistent
The first study was published in Sleep Advances in 2020. Specifically, this study aimed to determine whether wearing blue light blocking glasses had an impact on improving sleep, based on data compiled from 12 previous research studies.
The studies they chose included adolescent and adult participants and included people who had no sleep problems as well as those with sleep disorders. These studies took place over a period of a few days to a month. Participants in the included studies wear yellow or orange “blue blocking” glasses to filter out blue light.
The conclusion of this study is that previous research has not produced a consistent model to definitively say that blue light harms sleep. Some research has found that wearing glasses that block blue light helps, others have found that it makes no difference. This study also notes that the participant groups were very small and that the glasses seemed to have a better impact on those who suffered from sleep disorders than on those who did not. So, you may no longer need blue light blocking glasses if you don’t have trouble falling and staying asleep.
What you do on your phone may have a bigger impact on your sleep
The second study was published in Sleep Medicine Reviews in 2024. The question the authors sought to answer was whether using the technology itself caused people to have sleep problems, or whether what you do with that technology was more important?
The study found that the answer was very complex and nuanced. If you do something simple, like read a relaxing book or watch a nice movie, your sleep may not be affected. However, if you’re scrolling or playing a competitive game, you might have trouble falling asleep afterward. So it’s not necessarily just the blue light coming from the screen of your phone, tablet or TV. It’s what you watch and engage with specifically.
Research also highlighted that using technology before bed can take up valuable sleep time. You might decide to binge an extra episode, or hear a notification and see what it’s about. This pushes back the time you start sleeping further and further, so you don’t have enough hours. For those who have trouble sleeping, you can check out expert tips to help you. Keep in mind that, according to these studies, blue light itself may not be the enemy.
