It more or less has in mammals... though it's kind of swung the other way. Sunlight is required to produce Vitamin D, which it turns out is pretty darn important.
The catch is that most people don't get enough sunlight exposure to produce enough vitamin D.
Sure, except that drosophila are animals and we have a lot more in common with them than you think, especially when looking at more primal systems. Our intrinsic immune system was discovered in fruit flies, look up the Toll pathway.
> Drosophila are fruit flies. File under "interesting, but likely not applicable to mammals".
Why assume this, without specific evidence? Drosophila are used as a model organism partly because so many effects transfer. We all run on DNA, and our cells all use protein and RNA machinery.
If you are a human and not a fly here is what concerns you "... humans are exposed to more blue-enriched LED illumination for most of the day, or even at night due to shift work and light pollution in large cities.6 However, long-term consequences of increased daily blue-light exposure across the human lifespan are not known." saved you a clickbait.
There is a long running show called the nature of things in Canada that had an ep called 'lights out' discussing this subject in detail. Really interesting if one can see it.
Excessive blue light exposure mucks with our natural sleep cycle which leads to various health issues.
All: we've compressed the title in order to make space for the fruit flies. Now it is no longer baity.
This result is interesting in its own right, so hopefully the thread can proceed to talking about other bits than baity titles and insects not being mammals.
I made a (what most people would consider terrible) vim color scheme that has no blue light in it (it's like an old amber terminal). Initially I thought I would hate it and switch back in a couple days/weeks, but I actually find it very nice, and switching to anything w/ blue light or a "normal color scheme" with blues and greens now weirdly feels like an assault. Feel free to give it a whirl: https://github.com/camgunz/amber
Code on a phone!? When I first started it was an orange terminal, DOS3 something. @hyperpalluim is giving me the "Future Shock" I used to hear the old folks talk about...but still using VI?! On the phone!? I'm having some really mixed feeling now
bluetooth keyboard + ARM quad cortex-A53 1.3 GHz, 20 GFLOPS GPU, 1 GB RAM - for 70's era unix tools, it is unbelievably powerful. Specs in the billions.
Somewhat similar to my terminal text color code. Mine is FCAF3E on 150C0C background, which I find a bit more neutral and gentle to the eyes. The secret is to avoid pure or saturated colors which I found sometimes can be a punch in the eye, so I usually start with a color then lower its intensity and add a bit of the others to make it less hard to look at.
Yeah I try and make color schemes that work in 256 color terminals and I really lament the lack of options sometimes. Could be worth doing something clever, but having been a terminal Vim user for so long, I've built up a lot of resentment against color schemes that look great in GUI but not so great in terminal haha.
Yeah and there are other tools for other environments. I've found it hard to keep my setup aesthetically pleasing with them, and if you're doing anything with color or anything low contrast, they can make your life pretty hard. But yeah I mean, use whatever works for you, definitely.
I've read that even a monitor with only warm-collided pixels displayed on the screen will still emit "blue light", in which case this wouldn't solve the problem correctly. I wonder if this is true?
Blue light is only emitted if the blue subpixel is lit (well, except for some backlight leakage on LCDs). So it is possible to sit in front of a screen without any blue light. Of course, this means you can't produce most colors, so it's not ideal for general use, but it is possible.
When in bed at night, I often use a software filter to cut out all but red subpixels. This allows me to read or work without causing melatonin suppression. Just clamping blue and green to 0 is a very poor solution though; I should swap to a proper "redscale" filter (think greyscale, but only red subpixels) that is based on the luminosity of the source image. The dumb filter has definitely confused me a few times when I can't seem to highlight any text.
I suspect this isn’t the case with an OLED, since it wouldn’t even emit any blue light in the first place if those pixels aren’t on. However, a typical laptop / monitor will have a white backlight that then gets blocked. Often there’s bleed through even if the screen is completely black.
If someone with more specific knowledge about screens corrects me, I yield to their judgment. :)
tech writer who specializes in TV screens here. You are indeed correct. With OLED, no bleed-through at all exists since there is no backlight and unless specific RGBW pixels on the screen are activated, they emit no light at all basically. On the other hand, even the absolute best consumer market LCD/LED screens leak at least some backlight glow, though in high quality models it becomes very faint due to local dimming zones and high quality light blocking.
Oh yeah love CRT. Actually started out trying to use that but I don't have a great graphics card so it was a little laggy. I highly recommend running a terminal in gVim though; I've found it to be the best terminal on Mac OS.
Oh yeah I've been trying to give the world another unwanted programming language for a little while. This snapshot is from a tool I'm writing to generate C bindings--today glibc, tomorrow the world, etc.
White LED light is produced by a narrowband blue LED chip (450-460nm) coated with a wideband yellow phosphor (green-red). It's additive, the spectrum is built up. Some of the blue light is converted by the phospor. You are most certainly exposed to the blue light. Those flies were exposed to too much and for too long. This study starts with the premise that blue light is harmful and fails to demonstrate anything.
Most LED fixtures emit a lot of blue, even if the bulb appears a different color. As far as I know, "bug bulbs" are the only ones that actually filter out all the blue- which attracts bugs.
Blue (and any high energy light) is known to facilitate radical formation, redox and other electronic transitions, hence "ionizing radiation". It breaks chemical bonds. Fruit flies are small enough to be translucent to visible light. It is not unreasonable to think that blue photons wreak chemical havoc in the bodies of small bugs, not unlike x-rays in mammals.
Blue light is not ionizing radiation. In fact, not even UV-C is ionizing. You have to get shorter-wavelength than UV to ionize. UV is harmful because it has enough energy to at least excite electrons to higher energy levels which can lead to, I think, changes in bond rotations, but not outright ionization. UV is clearly dangerous, but not because it ionizes.
I'm not sure how the transparency argument is relative. You seem to be confusing energy, which depends on the frequency of individual photons with intensity, which is the number of photons. Shine all the low-energy photons you want, and you're just going to add heat, not create photo-products or ionize.
I'm not confusing energy with intensity, but in a silly moment I got the word "photoionization" with photodissociation/photolysis. Yes, you need hard UV to actually eject an electron from its atom, but you need far far less energy to break bonds and damage DNA. Photosynthesis is all about redox driven by blue and red photons.
These are more than just bond rotations (with only slim exceptions, bond rotations have the same energy state) from photostimulation. You can flip cis/trans bonds (main mechanism of retinal), ring closing in vit D, and cause all kinds of increased free radical activity [1]. In particular, blue light interacting with certain chemophores, such as catechins, are relatively prone to photoactivation [2].
Ever seen polycarbonate that's been around blue LED light sources (not sunlight) for a very long time? It yellows. That's not "just adding heat", that's chemical bonds breaking.
Transparent just means the entirety of the body can be bathed in light.
Insects aside, I realized there was something wrong about blue light much before any articles appeared about its negative effects on our circadian cycles. It was nearly 20 years back when I bought some of the then young blue and white leds to make some experiments with them, and I quickly realized I hated blue ones. No matter how I reduced the current through them, their light made me feel uncomfortable and didn't like as well cold white ones because they emit more blue light than warm white leds. I still have in a drawer those 10 leds I bought, none of them was ever used in any project. Unfortunately lots of gadgets appeared in the early 2k and they all used blue leds which were going to become the standard pretty much everywhere.
It was then when I realized how much and why I disliked that light: it made me nervous; I couldn't stare at a blue led light, especially the bright ones, for some time without feeling anxiety.
Then one day I read about how blue light affects us negatively and went "aha!". Now I mask or paint, or even swap where possible, all blue leds those lazy designers keep sticking into gadgets and appliances.
I recently got the Dasung Not-eReader and while it has its quirks it works pretty well overall, especially as mini-screen for my laptop. It is fast enough for me to work in vim without any ghosting. And it allows me to actually do some work outside. But I agree, having an actual eInk laptop would be fantastic.
What intensity of light, for how long compared to sunlight?
Every time I hear these blue-light crusaders I am reminded of that “iPads are bad for reading” so-called experiment where the iPads were fixed to the desktop set at maximum brightness with a custom font chosen by the experiment lead. Basically attempting to make life as uncomfortable for the subjects as possible, then blaming all the negative effects on blue light emitted by the iPad.
So short version: is this study meaningful in an way or does it shorten lifespan by using extremely bright blue light for many hours longer than a natural day/night cycle?
edit: they maintained similar photon flux density so the blue light would have been extremely bright to compensate for being a single wavelength.
Edit2: the actually useful words in that linked paper are about two paragraphs, the rest is baseless speculation. An effect was observed, with no mechanism described, therefore extrapolation beyond the experimental conditions is entirely in the realm of fan fiction and soap opera (ie: emotive drama).
The study is worth reading. The light exposure was for 12 hours/day, they showed steadily increasing mortality with increasing photon flux density of blue, and they showed that white light exposure with blue filtered out (at the same intensities) did not have the same effect.
They also did not test increasing photon flux density of white/filtered light. They only bothered controlling for PFD after introducing filtered light.
Sounds like experimental protocol was invented … on the fly.
Also, white light with the blue filtered out is not an appropriate control condition. What's to say the blue light flies didn't just deteriorate normally and the artificially filtered white light had a positive health effect for the control group?
To all the non-biology people saying essentially "meh, flies," we're not as different from flies as you might think. Model organisms aren't just chosen because they're easy to study. They're chosen because At the genetic, molecular, and cellular level results actually transfer to us. This may not be obvious if you haven't done advanced studies in biology.
I’ve been working with a fly lab the last few years. They really do model diseases and gene functions. There are tools to look up genes across species and determine how close they are (othologs). Plus cheaper to study.
For example circadian rythmns were discovered in flies first:
Is there some demonstrable decrease in longevity for sailors (absent the obvious mortality risks of drowning)? It seems to me that if there was a fundamental problem with humans dealing with long-term exposure to blue light, admittedly reflected rather than directly emitted, it would show up in either sailors or those that live along ocean coastlines.
Of course it's possible that reflected blue light has different effects.
It took me a minute to figure out what you're getting at but I suppose you mean "blue light" reflected from the blue surface of the ocean? The ocean appears blue-ish because it absorbs the other colors, not because it is emitting blue light. and the amount reflected is really rather paltry compared to that being emitted from the sun, hence the dark color. I don't think this change in frequency distribution is at all significant compared to LEDs, which natively emit blue light and in common application use phosphors to approximate white light while still largely being composed of the blue part of the spectrum.
What this consternation overlooks is that LEDs that more faithfully replicate the spectrum of a black body emitter do exist ("high CRI (Color Rendering Index)" fixtures), they just aren't in common use because they are more expensive. I'm not sure if anyone is working on a high CRI LCD.
This is confusing to me, would love if someone helped elucidate the details. My previous understanding was that bluelight is harmful because bluelight visually interferes with the body's circadian rhythm by leading the body to believe it's still daytime when it may not be.
This article says that "any bluelight is bad", is that incorrect? I don't understand, isn't bluelight measured as light on the 450nm range of the electromagnetic spectrum, whereas visual sunlight ranges from 400-700nm? So, is the thesis that light at 450nm from the sun is only emitted when the sun is highest in the sky, for a few hours a day, whereas bluelight from screens is ever present—causing the circadian rhythm to go out of whack (?).
The article also states that blue light on any part of the body may cause mitochondrial damage. I wonder if the most proactive biohackers would be inclined to wear long-sleeves at non-peak hours to counter this problem. [0]
Maybe this is why Dave Asprey is seen always wearing his blue light blocking glasses, even during daylight hours.
I am also not so inclined to dismiss this data because it only addresses fruit flies. It seems natural to believe that the closer we get to following the circadian cycles we evolved alongside with, the more likely our bodies are to behave optimally. Sure, we may be more resilient to these types of stressors than fruit flies, but, we already know that obeying circadian cycles is a key component to achieving better health, and the work of this paper just seems to push that idea a bit further than we may have originally been lead to believe. It doesn't take much of a stretch of the imagination to guess about how these factors could affect us.
I only use nightlight (~red tint) on all of my devices at all times and people think I'm crazy. I can't even go back to normal -- it physically hurts and everything just looks super blue.
Wanting to lower the energy of photons that are about to hit your face and get focused into the back of your eye is completely reasonable. The only argument against this practice is that the effects of LED screens is negligible, which is apparently false according to this paper.
Blue Light FUD is an industry now. Although blue light exposure at night is detrimental due to melatonin blocking, during the day, it's important - both blue spectrum light and brightness. The fact that we spend most of the time indoors during the day is one of the reason of the wide incidence of myopia (shortsightness).
I warned LensCrafters that they may expect class action lawsuits as they call blue light "harmful" and offer coating, which reduces blue light both during the day and at night, which could be a trick to make people shortsighted to sell them prescription eyeglasses later.
> Multiple factors are involved in the development of myopia [18]. Both genetics and the environment play a role in the development and progression of myopia. Many epidemiological surveys have shown that excessive close-up work, a high level of education, and participation in fewer outdoor activities were important environmental risk factors for myopia [9,19–24]. Genetic factors have been proven to play a significant role in the development of myopia, and several genes are associated with high myopia [18,25–30].
Thanks! I'm myopic, have higher ed degrees, and work as a luthier specializing in restoration work (excessive close up work for long hours). I knew it was partly genetic looking at family history but had no idea that my everyday work was compounding the problem.
Myopia has become massively more prevalent over the last century, so we know there are environmental factors that are significant contributors to risk of contraction.
So to bring this a little bit back to biology (and away from the fact that the article says little about humans) I would conjecture that the issue with blue light may stem from Rayleigh scattering [1] of sunlight and the subsequent phenomenon whereby the light that reaches us has a lot of the blue component removed.
In the late afternoon, all the blue light get caught and even some of the red, since the sun is now not just an atmosphere-length but an atmosphere length plus a radius of the earth length from the observer and hence has more distance to get scattered. This would mean we get orange-ish light.
I always wondered: is there anyway to distinguish an evening from a morning through the sort of light we see. So Image you see random pictures and don’t know if it’s dawn or dusk. Can you see the difference?
Interestingly enough, if you aren’t familiar with the location, there’s no foolproof method to tell whether it’s morning or evening by light alone. There may be cues, like if it’s a city then the properties of light could reflect the denser pollution it has to penetrate in the evening, but that still depends on location and time of year.
I sincerely thought I could tell mornings from evenings by light alone, until I congratulated a friend on a great capture of evening light and he told me the shot was taken in the morning. Did some research after that.
90 comments
[ 3.6 ms ] story [ 170 ms ] threadI wouldn’t expect the same results in mammals (or any animals really).
The catch is that most people don't get enough sunlight exposure to produce enough vitamin D.
They can still be merged in teleportation accidents.
> Daily blue-light exposure shortens lifespan and causes brain neurodegeneration in Drosophila
Drosophila are fruit flies. File under "interesting, but likely not applicable to mammals".
EDIT: From front page to flagged in 32 minutes. That's impressive.
Why assume this, without specific evidence? Drosophila are used as a model organism partly because so many effects transfer. We all run on DNA, and our cells all use protein and RNA machinery.
[1] https://twitter.com/justsaysinmice
Excessive blue light exposure mucks with our natural sleep cycle which leads to various health issues.
This result is interesting in its own right, so hopefully the thread can proceed to talking about other bits than baity titles and insects not being mammals.
BTW: I code on a phone, and set the colour temperature to warm (at night; cold during day).
aapt, apkbuilder, signer (for android apps)
bluetooth keyboard + ARM quad cortex-A53 1.3 GHz, 20 GFLOPS GPU, 1 GB RAM - for 70's era unix tools, it is unbelievably powerful. Specs in the billions.
- orange #ff8700 for text
- darker orange #d75f00 for bold
- lighter orange #ffaf00 for comments
- red #5f0000 for errors
- dark grey #1c1c1c (and #121212) for backgrounds (text in the lighter themes).
- off yellow #875f00 and #afaf00 for some status/wild menu
- git diff orange #ff5f00
When in bed at night, I often use a software filter to cut out all but red subpixels. This allows me to read or work without causing melatonin suppression. Just clamping blue and green to 0 is a very poor solution though; I should swap to a proper "redscale" filter (think greyscale, but only red subpixels) that is based on the luminosity of the source image. The dumb filter has definitely confused me a few times when I can't seem to highlight any text.
If someone with more specific knowledge about screens corrects me, I yield to their judgment. :)
[1] https://github.com/Swordfish90/cool-retro-term
That's rather comforting to me as most if not all LED fixtures have these.
Being in total darkness was the best? and by how much compared to light with blue removed?
It's also possible it's due to the retinal damage which caused early mortality?
I'm not sure how the transparency argument is relative. You seem to be confusing energy, which depends on the frequency of individual photons with intensity, which is the number of photons. Shine all the low-energy photons you want, and you're just going to add heat, not create photo-products or ionize.
These are more than just bond rotations (with only slim exceptions, bond rotations have the same energy state) from photostimulation. You can flip cis/trans bonds (main mechanism of retinal), ring closing in vit D, and cause all kinds of increased free radical activity [1]. In particular, blue light interacting with certain chemophores, such as catechins, are relatively prone to photoactivation [2].
Ever seen polycarbonate that's been around blue LED light sources (not sunlight) for a very long time? It yellows. That's not "just adding heat", that's chemical bonds breaking.
Transparent just means the entirety of the body can be bathed in light.
[1] https://www.ncbi.nlm.nih.gov/pubmed/15797866
[2] https://www.ncbi.nlm.nih.gov/pubmed/29973539
EDIT> cis/trans retinal -- should have remembered that
Modern street lights seem worse than most people think in this case.
Every time I hear these blue-light crusaders I am reminded of that “iPads are bad for reading” so-called experiment where the iPads were fixed to the desktop set at maximum brightness with a custom font chosen by the experiment lead. Basically attempting to make life as uncomfortable for the subjects as possible, then blaming all the negative effects on blue light emitted by the iPad.
So short version: is this study meaningful in an way or does it shorten lifespan by using extremely bright blue light for many hours longer than a natural day/night cycle?
edit: they maintained similar photon flux density so the blue light would have been extremely bright to compensate for being a single wavelength.
Edit2: the actually useful words in that linked paper are about two paragraphs, the rest is baseless speculation. An effect was observed, with no mechanism described, therefore extrapolation beyond the experimental conditions is entirely in the realm of fan fiction and soap opera (ie: emotive drama).
Sounds like experimental protocol was invented … on the fly.
For example circadian rythmns were discovered in flies first:
https://www.nobelprize.org/prizes/medicine/2017/press-releas...
Disease research also is done:
https://dmm.biologists.org/content/9/3/235
Of course it's possible that reflected blue light has different effects.
What this consternation overlooks is that LEDs that more faithfully replicate the spectrum of a black body emitter do exist ("high CRI (Color Rendering Index)" fixtures), they just aren't in common use because they are more expensive. I'm not sure if anyone is working on a high CRI LCD.
This article says that "any bluelight is bad", is that incorrect? I don't understand, isn't bluelight measured as light on the 450nm range of the electromagnetic spectrum, whereas visual sunlight ranges from 400-700nm? So, is the thesis that light at 450nm from the sun is only emitted when the sun is highest in the sky, for a few hours a day, whereas bluelight from screens is ever present—causing the circadian rhythm to go out of whack (?).
The article also states that blue light on any part of the body may cause mitochondrial damage. I wonder if the most proactive biohackers would be inclined to wear long-sleeves at non-peak hours to counter this problem. [0]
Maybe this is why Dave Asprey is seen always wearing his blue light blocking glasses, even during daylight hours.
I am also not so inclined to dismiss this data because it only addresses fruit flies. It seems natural to believe that the closer we get to following the circadian cycles we evolved alongside with, the more likely our bodies are to behave optimally. Sure, we may be more resilient to these types of stressors than fruit flies, but, we already know that obeying circadian cycles is a key component to achieving better health, and the work of this paper just seems to push that idea a bit further than we may have originally been lead to believe. It doesn't take much of a stretch of the imagination to guess about how these factors could affect us.
[0] https://www.nature.com/articles/s41467-018-02934-5
Wanting to lower the energy of photons that are about to hit your face and get focused into the back of your eye is completely reasonable. The only argument against this practice is that the effects of LED screens is negligible, which is apparently false according to this paper.
I warned LensCrafters that they may expect class action lawsuits as they call blue light "harmful" and offer coating, which reduces blue light both during the day and at night, which could be a trick to make people shortsighted to sell them prescription eyeglasses later.
-- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6261017/
I think it was 660 or 670 nm (red light)
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4148276/
Was very surprised by how much light coming in from the city was keeping me awake.
Taking melatonin worked for a while but I feel like it really messes with you.
In the late afternoon, all the blue light get caught and even some of the red, since the sun is now not just an atmosphere-length but an atmosphere length plus a radius of the earth length from the observer and hence has more distance to get scattered. This would mean we get orange-ish light.
Have biologists pointed this out?
[1] https://en.wikipedia.org/wiki/Rayleigh_scattering
In the morning, if there is less dust, then there would be different Raleigh scattering.
I sincerely thought I could tell mornings from evenings by light alone, until I congratulated a friend on a great capture of evening light and he told me the shot was taken in the morning. Did some research after that.