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Daily blue light shortens lifespan, causes brain neurodegeneration in Drosophila

nature.com

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

#41

Post by ip26 »

manicdee wrote: post #38

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…

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.

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

#42

Post by manicdee »

ip26 wrote: post #41
manicdee wrote: post #38

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…

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.

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

#43

Post by JabavuAdams »

philpem wrote: post #8

Nice clickbait. Full title of the article: > 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.

> 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.

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

#44

Post by JabavuAdams »

kortex wrote: post #25

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.

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

#45

Post by JabavuAdams »

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.

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

#46

Post by mkagenius »

camgunz wrote: 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…

Wait for them to repeat the study with orange light and then completely stop using vim. Then even orange will feel like an assault.

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

#47

Post by Florin_Andrei »

kortex wrote: post #25

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.

This is military grade bullshit.

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

#48

Post by atombender »

camgunz wrote: 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?

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

#49

Post by learc83 »

idnefju wrote: post #22
k__ wrote: post #21

Earlier quoted context omitted.

I read somewhere that getting vitamin D is easier through sunlight than people think.

Of course it also depends on your pigmentation and where you live.

And time of year.

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

#50

Post by fallous »

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.

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