Smartphones can really come in handy in the bedroom, like for reading in bed at night without bothering your partner, falling asleep to your favourite ASMR video, and even for waking up without an actual alarm clock. But what’s the deal with the connection between sleep and blue light from phone and tablet screens? Is it really true that using your phone in bed is bad for sleep? And what can we do to get better rest?
If you’re the kind of person who always takes their phone to bed, you’ve probably asked yourself these questions. We’ve dug through current studies to help give you some answers.
Article Overview: How blue light affects sleep |
Our faithful bed buddy, the smartphone
Falling asleep next to your smartphone. You probably do it, and you’re definitely not alone. Our mobiles have replaced the TVs and books that we used to wind down and fall asleep with in the evenings. Use of smartphones in the UK has increased rapidly in recent years – and so has the number of people who suffer from sleep disorders. It’s understandable that many have pointed to a connection between blue light and sleep disorders. But is it really causation, or simple correlation?
Much research is currently being done around how digital media use relates to sleep quality. Studies suggest that people who use their smartphone shortly before falling asleep seem to experience less restful sleep. This was the result of one Norwegian study in which nearly 10,000 young people were asked about their mobile phone usage and sleep quality.
A Belgian study confirmed the same for adults: those who used their mobile phone at bedtime reported that it took longer to fall asleep and that they slept more poorly. However, with both studies, the information on sleep quality was obtained with the help of questionnaires, which means participants’ answers were subjective and could have distorted the results.
Another caveat of both studies: They didn’t make statements about whether sleep disturbances were triggered by the devices themselves. Other than a phone’s blue light, sleep could be affected for plenty of reasons: an intriguing WhatsApp chat, an exciting game, even electromagnetic radiation—or none of the above.
A Swedish-American study tried to shed some proverbial light on the matter. They investigated whether having a mobile phone near the bed could trigger sleep disorders due to radiation. And the results seemed to indicate so: the study group that was exposed to 884 MHz radiation—a typical frequency for mobile phone radiation at the time—fell asleep later and slept worse through the night. But the study was conducted in 2008 with only 35 men and 36 women participating, which limits its significance in multiple ways.
These studies seem to show that sleeping next to a mobile phone promotes sleeping disorders. Yet the reasons why are difficult to determine and the results not absolutely conclusive. So let's take a closer look at one of the main suspects for poor sleep: blue light from screens, which is said to make sleeping at night more difficult.
Does blue light really affect sleep?
Is blue light harmful? To answer this question, we first need to know what blue light is in the first place. For one, it doesn’t necessarily look blue to our eyes. Going back to physics class, we know that light consists of different wavelengths—longer and shorter—and that blue light is on the shorter end of the spectrum, and thus more energetic.
Blue light itself is not harmful in moderation. It’s actually part of sunlight, which helps our bodies produce precious vitamin D. Artificial light sources like the screens of mobile phones and computers also radiate blue light. But we generally position these screens closer to our faces than we do to the sun, so the concentration of blue light that reaches our bodies can also be higher.
One interesting clue to this puzzle is that our brains cannot easily distinguish between blue light from sunlight or an iPad. The blue light contained in daylight affects the circadian rhythm, meaning that sunset signals to our brains that it’s almost bedtime. With the onset of darkness, the "sleep hormone" melatonin and other substances are naturally released by our bodies.
This raises the main question: Does artificial blue light cause our body to think it’s still daytime, so it releases less melatonin and affects our ability to fall asleep or sleep through the night? In a way, yes, according to a 2019 Finnish meta-analysis that evaluated nearly 130 scientific articles. They concluded that two hours of blue light exposure in the evening can actually suppress melatonin production—but only for about 15 minutes.
So it appears that exposure can be disruptive to sleep, but as far as current research has shown, that negative effect of blue light on sleep is limited. Maybe that means you can stop wearing those blue light-blocking glasses for sleep. But does this mean blue light before sleeping gets the green light? Not quite, because even if blue light is guilty as charged, it may be one of many culprits from your smartphone.
Better sleep without screens
If you’re seeking better sleep, good sleep hygiene is what you should be focusing on, and it’s simply easier to achieve without a phone in the bedroom. It may not necessarily be that your sleeping problems come from blue light exposure, but smartphones, tablets and laptops keep our minds active in a way that doesn’t really promote sleep.
If you've read our all-round guide to falling asleep better and improving sleep quality, you'll know that restful sleep is all about relaxing and winding the mind down. This is exactly what becomes difficult when we use our devices right before going to sleep, because our screens are often projecting things like:
- E-mails that remind us of waiting tasks and thus trigger stress
- Games that make us feel excited or put us on edge
- Chats or voice messages that set us off
- An endless newscycle that can make us feel angry or hopeless
- Other things that keep us awake and chisel away at precious sleeping time
A quiet bedroom, regular schedule and soothing activities before bedtime can make it easier to fall asleep and stay that way. One idea is to make time for relaxing with a vape pen to calm down and reflect on your day. Or end the day with a little pre-bedtime snack made with sleep-inducing foods, time-tested as home remedies for better sleep. You can also try our new CBD NIGHT CAPSULES WITH 5-HTP. 🌚
So in short: Science hasn’t come to a definitive conclusion about digital devices, but there’s still plenty to think about if you’re on a mission to get better sleep. Even if it's not the blue light that's keeping you awake, try breaking up with your electronic bed buddy and make the bedroom off-limits.
