The public freakout about blue light started with a study in 2014. Half of the 12 participants read on an iPad before bed. The rest read physical books. The iPad users took longer to fall asleep, felt groggier the next day and produced less melatonin. The researchers said the culprit was the glow emitted from the iPad’s LED screen, which produces a disproportionate amount of light in the upper, bluer end of the spectrum. Under specific circumstances, blue-enriched light disrupts the daily circadian rhythm – our body’s natural pacemaker – that uses daylight to help determine when we start to feel tired. Subsequent research seemed to support the findings. Sounds simple, right? It’s not.
“This was an incredibly deceptive piece of work,” says Jamie Zeitzer, a professor of psychiatry and behavioural sciences at Stanford University, who studies the effect of light on the circadian system. The science wasn’t bad, he says, the problem is it brought people to bad conclusions.
After years warnings and millions of people flipping on the blue light filters built into their phones, the latest science suggests screens are not the main culprit here after all. For example, a recent review of 11 different studies and found that the light from screens only delayed sleep by about nine minutes, at worst. Not zero, but not life altering, either.
The amount of blue light emitted by the screens of phones, laptops and tablets has also been shown to be tiny compared to the blue light we receive from the Sun – 24 hours-worth of blue light from digital devices totted up to less than one minute spent outdoors, according to one study. Other studies have shown it’s not enough to affect levels of the hormones that control our sleep.
So why am I so tired all the time? Zeitzer and others told me there are lots of other ways that light, blue and otherwise, could be ruining my bedtime. If I really wanted to tackle the blue monster, it was going to take a serious lifestyle change.
Seems to align with my personal experience that turning on the filter (but also really turning down the brightness more than the default settings on the phone allow) makes me fall asleep sooner, but that could easily be from just training myself over time that this is the signal to start the sleep shutdown process.
I have a wild theory that humans needs the full spectrum of natural sunlight nearly every day for at least an hour or so. It’s known already that is creates vitamin D. I think other unknown effects happen and that the screens people stare at are not providing the same spectrum, resulting in a lack of wavelengths that we need to stay healthy.
Newton and Tesla both have anecdotal stories about staring at the sun (or it’s reflection) and being inspired by it as well. There are others as well.
It’s a crazy idea, I know, but what if, under certain rare circumstances, viewing the sun unlocks certain mental capabilities and enhances the mind or body of the person who experiences it in unexpected ways?
I’m not saying anyone should stare at the sun obviously, I simply think there’s so much more to light than we understand and that limiting wavelengths, in my opinion, will only prevent such an occurance, if it were something that actually existed.
I don’t care about sleep, the blue is painful, the yellow is not.
Hot take: Manipulative and mentally destructive social media algorithms are the reason your sleep is disrupted. It’s what is on the screens that is the problem, not what color it is.
But of course, the tech companies would rather have you blame the color of the screen than their own products. I’m sure they loved adding those color-shifting features to their next products too. not only do they avoid the blame, they get to sell you the “solution”.
If anything the blue light filters make your phone easier on the eyes at night, so you can doomscroll longer.
I’m curious if any part of this is that modern OLED screens are much less blue than 2012’s LED backlit screens, which affect reproducing the study.
Also, beware the tyranny of averages!
An average of 9 minutes can be some part of the population unaffected while another is massively affected.
And agree with others, unless you’re reading books, you’re probably reading email and social media before bed, and the last thing I want before sleep Is to stimulate my brain into thinking. Reading a book really helps with that.
Blue light is visible, so emitting more or less blue light Alters how colours are perceived on the display. That’s also why enabling the blue light filter makes the screen look yellow.
Screens calibrated for the same colour temperature and wilth equal brightness should emit the same amount of blue light regardless of which display technology they use.
“The more light that you get during the daytime, the less impact the light in the evening has,” Zeitzer says. The pre-pandemic world exposed people to a lot more light than they realised. There’s the Sun during a commute, the piercing fluorescent bulbs of an office, a walk to lunch. Now, so many of us roll out of bed and sit under the same lighting conditions until we go to sleep. Our bodies can’t tell the difference between day and night.
RTO propaganda! /s
unsarcastically this. Days I wfh, I get to enjoy my coffee on the deck in the morning sun, and go outside for lunch when the weather is nice. Meanwhile my desk and lab are in the basement so I rarely see the sun when I go into the office.
I’ve never cared about whether or not it affected sleep. A warm tone is just more pleasant in the dark I think, especially if you can’t get dark mode.
Regardless of the effect on circadian rhythm, I wonder if there’s any research on eye strain. I personally felt less strain when turning on dark mode or sepia filters, even in the evening.
So blue light is not ruining our sleep because it’s just responsible for 9 minutes of sleeplessness, did I get that right?
That’s a small point. The larger point is people’s lifestyles. While there may be a small subset of the population that is especially sensitive to blue light for most people it comes down to your lifestyle and how and when you are exposed to light. More blue light, specifically sunlight earlier in the day is better. As evening approaches dial back your exposure to blue light. Same with the content you consume. Read the social media and bad news in the morning, less in the evening.
Interventions to reduce short-wavelength (“blue”) light exposure at night and their effects on sleep: A systematic review and meta-analysis https://academic.oup.com/sleepadvances/article/1/1/zpaa002/5851240?login=false&guestAccessKey=
A bidirectional model of sleep and technology use: A theoretical review of How much, for whom, and which mechanisms https://www.sciencedirect.com/science/article/pii/S1087079224000376
Lol! Wut? Is this person stupid? Since when is the color of the light, the problem? It’s the fact that you scroll when you should be winding down for the night, and then keep scrolling well past the point when you should be sleeping.
I actually feel terrible the following morning of I fall asleep after doing stuff on my phone (which is most of the nights). If not because of the blue light, then why?
The things you are exposing yourself to on your phone?
Thank you for the detailed answer and overview of the different options! To clarify about Signal: in order to confirm a new account, Signal sends an SMS with a code to the registered number. In Russia, you cannot receive those messages since maybe 2 years ago. So all existing users are fine, but the new users can’t register an account.
Edit: typos
Bruh I feel like shit when I get up at 7 AM after I’ve been doom scrolling till 4 in the morning, it must be the blue light man, must be
The electromagnetic field being generated by your phone pinging the nearest cell tower 30 times a second.
