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Daily blue light shortens lifespan, causes brain neurodegeneration in Drosophila

nature.com

51–60 of 91 posts

Re: Daily blue light shortens lifespan, causes brain neurodegeneration in Drosophila

#51

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:

https://www.nobelprize.org/prizes/medicine/2017/press-releas...

Disease research also is done:

https://dmm.biologists.org/content/9/3/235

Re: Daily blue light shortens lifespan, causes brain neurodegeneration in Drosophila

#52
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.

[0] https://www.nature.com/articles/s41467-018-02934-5

Re: Daily blue light shortens lifespan, causes brain neurodegeneration in Drosophila

#53
post #13

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/camg…

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.

Re: Daily blue light shortens lifespan, causes brain neurodegeneration in Drosophila

#55
post #50

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 ef…

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.

Re: Daily blue light shortens lifespan, causes brain neurodegeneration in Drosophila

#56
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.

Re: Daily blue light shortens lifespan, causes brain neurodegeneration in Drosophila

#57
post #41

Earlier quoted context omitted.

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?

Re: Daily blue light shortens lifespan, causes brain neurodegeneration in Drosophila

#58
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.

Re: Daily blue light shortens lifespan, causes brain neurodegeneration in Drosophila

#59
post #58

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…

I thought that myopia was more of a genetic inherited trait than related to time spent indoors.

Re: Daily blue light shortens lifespan, causes brain neurodegeneration in Drosophila

#60
post #59
post #58

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…

I thought that myopia was more of a genetic inherited trait than related to time spent indoors.

> 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].

-- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6261017/

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