Scientists Are Debunking The Effect Of Blue Light On Sleep - Here's How

It's often been thought that the blue light that comes from the screens of electronic devices can ruin your sleep. This is because blue light can suppress melatonin, which is responsible for making you sleepy. Less melatonin means a harder time falling and staying asleep. When you've got a busy schedule the next day full of important work, household errands, and meetings, you definitely want all the sleep you can get. Previously that meant that you should avoid blue light before bed. However, is that still the case?

Scientific studies are working on answering just that question. One study decided to look at previous research done as a whole and compare the data to see if all findings were consistent that blue light before bed will result in poor sleep. Instead, they found previous research to be inconsistent in its findings. Using your phone before bed does not necessarily mean you won't sleep well.

Another study examined sleep from a different angle. It took into account not just blue light, but the use of the technology in general. Were people enjoying a movie before bed, or were they arguing with strangers on social media? This study found that the mental and emotional stressors from technology use may be a better indicator if you have trouble sleeping, not just blue light by itself.

The first study was published in Sleep Advances in 2020. In particular, this study was looking at if wearing glasses that block blue light has any impact on improving sleep based on data compiled from 12 previous research studies.

The studies they chose included both adolescent and adult participants and included people who had no trouble sleeping as well as those with sleep disorders. These studies took place over the course of a couple days up to one month. Participants in the included studies work yellow or orange-tinted "blue-blocker" glasses to filter out the blue light.

What this study concluded was that previous research didn't yield a consistent pattern to make the definitive claim that blue light harms sleep. Some research found wearing glasses that stopped blue light to be helpful, others found that it made no difference. This study also notes that participant groups were very small, and that the glasses seemed to have a better impact on those with sleep disorders, rather than those without. So, there may be no need anymore for blue light glasses if you otherwise don't have trouble falling and staying asleep.

The second study was published in Sleep Medicine Reviews in 2024. The question the authors were seeking to answer was if using technology itself causes people to have trouble with sleep, or does what you do with that tech matter more?

The study found the answer to be very complex and nuanced. If you are doing something simple, say reading a relaxing book or watching a cozy movie, then you might not have your sleep impacted. However, if you are doom scrolling or playing a competitive game, then you might have trouble falling asleep afterward. So it is not necessarily just blue light from the screen of your phone, tablet, or TV. It is what you are looking at and engaging with specifically. 

The research also pointed out that the use of technology before bed can take up valuable sleep time. You might decide to binge one more episode, or hear a notification and look to see what it is. That pushes the time you start your sleep back further and further so that you are not getting enough hours. For those who have trouble sleeping, you can look to tips from experts to help you out. Keep in mind that, according to these studies, blue light itself may not be the enemy.