Blue light is very, very bad.

[emphasis added]

See also: The problem with f.lux . (a reminder that the pump for LEDs is blue-white light, which is always present despite software filters like “f.lux” that change the apparent color temperature by mixing in a larger amount of red and yellow light on top of the basic blue-white)

I don’t believe there is anywhere near the necessary clinical and experimental evidence at this point to claim that there is a causal link between exposure to computer-generated light and cancer. While some melatonin suppression has been shown in very controlled experimental conditions in preliminary studies, the effect on sleep across the general population, if any, is not yet known.

It’s not “computer generated” light at issue — you get the same problem without computers.

Computers and phones are mentioned because many of them nowadays use either fluorescent or LED lights, both of which happen to have peak emission in the very narrow range that suppresses melatonin. And yes, LEDs are fluorescent light sources, driven by a blue-white emission moderated by one or more phosphors to shift the color temperature.

The light from, say, a monochrome VT100 green or amber screen would be computer generated light, but wouldn’t affect melatonin production.

https://cancerres.aacrjournals.org/content/66/20/9789.long
“studies have suggested several mechanisms for the known effects of melatonin”

Much like tobacco, it took a long time before mechanisms were figured out to explain the observed correlation with cancer.

Sunlight coming through a windows is hundreds of times more dangerous, not just blue but in the whole spectrum, so if you really are concerned about cancer you should probably lock yourself in a dark room.

But if you look at the article cited in the original post, which is what most of us are commenting on in this thread, you can see it is computer and other human-generated light the thread is about. I think avoiding normal doses of nature-made blue light is possible only with eyeglasses or other lenses made for that purpose and worn when one is outside or near a window - but that comes with obvious drawbacks/costs.

Your comment about it taking a long time to figure out the mechanisms behind the observed correlation of tobacco with cancer is difficult to understand, in light of the fact that tobacco is not comparable to blue light from human sources. There is today no proven correlation between human-generated blue light and cancer at the levels most people are getting every day.

You can look this stuff up. Seriously, the information is available.

The mechanisms are being worked out, e.g. if you read the linked article at https://cancerres.aacrjournals.org/content/66/20/9789.long you saw this:

Harvard study strengthens link between breast cancer risk and light exposure at night
August 18, 2017 1.36pm EDT Updated August 21, 2017 12.16pm EDT

Artificial Light at Night and Cancer: Global Study
Asian Pac J Cancer Prev. 2016; 17(10): 4661–4664.
doi: 10.22034/APJCP.2016.17.10.4661

https://www.cnn.com/2016/06/21/health/led-streetlights-ama/

Melatonin levels increase after sunset and decrease again when daylight (or artificial light in the critical wavelengths) occurs.
Melatonin suppresses cancer, as well as controlling circadian rhythm and sleep.
It’s artificial light in the blue range at night that’s of concern here. Not daylight.

I often find it’s useful to put my opinion into a Google or Scholar search
like this: scholar light night cancer at DuckDuckGo
before posting what I believe; often what I think I know turns out to be old information.

LOL, I follow most of those... I just feel better on the journey. Yoga/meditation was and still is a lifesaver. Had a "hinge moment" just a month ago that made me stop the junk food and sugar. (pain doctor lowered the boom on diet vs. messed up back) More energy. Feel better. All of my joints feel much better, lost 15 lbs.

Just turned 65 so I'm taking the blue light thing seriously but not obsessively. Thanks for the article.

However...

"No one here gets out alive!" (Jim Morrison) I don't worry 'bout that too much.

Yeah, we switch to low- or no-blue light in the evening, about 8PM, and doing that ended our “up til 1AM” insomnia problems.
Reading late into the evening under a cool white compact fluorescent was a big dose of blue light we did not need.
Now we use either amber-filtered CFLs or amber LED floodlights, ceiling bounced — ample evening light;
and Rosco theatrical filter gels in Canary or Goldenrod over the computer screens.

I’ve found the MrBeams amber lights quite useful — bright motion sensors, plenty of light for getting around without tripping over the dog.

Phones these days has night mode , my iPhone turns night mode on at 23:00 and turns off at 07:00

It changes the screen to a warmer tint

It’s quite a different colour comparison to normal day mode
I might do an experiment for a week of night mode warmer tint screen and see if anything changes in my eyes

OMG, LOL
for a moment there I actually thought you were talking about my beer! :open_mouth:

Its not bad :beer:

Yellow light is apparently worse than blue now, according to new studies…lol

yellow snow is also bad

If you look up the evidence related to the topic in this thread, rather than posting false statements and smears about what I have read or not read before commenting, you will see that what I’ve posted is correct. There is no scientifically established causal connection between artificial blue light and cancer in humans. The articles citing preliminary studies that you mentioned don’t change that.

Well, this quickly becomes a religious argument about what’s “scientifically causally proved” — been there, done that, no point.
As the Harvard page says, that epidemiological work is

And yes, “no proven scientific mechanism” was the big tobacco argument for decades, until it wasn’t. And you’ll still find people who think it ain’t so.

=

Mice wake up at dusk: Rats and mice are nocturnal with most activity taking place between approximately one half hour after sunset to about one half hour before sunrise. So it makes sense that their circadian clock timing should work as described.

=

I’ve heard from researchers in the field that the LED industry is investing a lot of money in denial, too, I’d guess that’s because your basic blue-white LEDs are cheaper and easier to make than multiple-phosphor color corrected emitters, so the push is to sell the cheap ones. E.g. this, which I’d call obviously bogus:

What you seem to be doing is not very different from what the tobacco industry did: selectively look up studies that support your point of view and post the quotes. From your posts I get no idea what the concensus is in the scientific community about the subject.

As Hank stated above mice are nocturnal animals, which is the complete opposite of humans. I’m surprised this study didn’t mention this very important fact. Was it because of ignorance or did the researcher had any other intentions?

I’m not going to argue if blue light exposure at night time correlates with increased cancer risk. However, from my experience, using warm white light with very low blue wavelengths (E21A 9080 modded lights) at night, I often find myself getting sleepy much faster than with lights with higher blue wavelengths. Sometimes when I work into the wee hours, I ceiling bounce my CW flashlights and it works wonders in keeping me awake and alert.

Once after I repaired/upgraded Windows, it turned off my night light settings. For over a week, at night time I found my eyes irritated and squinting at the screen. When I realized the setting was turned off, I turned it back on and immediately felt the difference in my eyes. I no longer felt the need to squint due to eye strain.

Yes you can say it is anecdotal evidence but for me it is science because adjusting blue light exposure level has “repeatedly” made observable difference for “me” after continuous testing.

Sure. Even when there’s a published consensus statement, as from the American Medical Association, you’ll find pushback from the industry selling the product.

Here’s a short summary history of the field:

Environ Health Perspect. 2010 Jan; 118(1): A22–A27.
doi: 10.1289/ehp.118-a22

What’s in a Color? The Unique Human Health Effects of Blue Light

Hat tip to Soylent News

Let There be ‘Circadian’ Light |
| from the Oh dept. |
| posted by Fnord666 on Saturday February 22, @20:24 (Science) |
| Let There be 'Circadian' Light - SoylentNews |
———————————————————————————————————————————————

[0]martyb writes:

[1]Let there be ‘circadian’ light:

Researchers said the wavelengths at sunrise and sunset have the biggest impact to brain centers that regulate our circadian clock and our mood and alertness.

Their [2]study, “A color vision circuit for non-image-forming vision in the primate retina,” published in Current Biology Feb. 20, identifies a cell in the retina, which plays an important role in signaling our brain centers that regulate circadian rhythms, boost alertness, help memory and cognitive function, and elevate mood. (See [3]interview with lead researchers)

[…] Lead author Sara Patterson, a graduate student in neuroscience at the University of Washington School of Medicine, said how we set our internal clocks to the external light-dark cycle has been studied a lot. But how the changes in the color of light affect our brain has not.

“Color vision used for something other than color perception was the most exciting part for me,” she said.

In the study, Patterson and colleagues identified a cell known as an inhibitory interneuron or amacrine cell in the retina, which signals to photosensitive ganglion cells that affect our circadian brain centers. The researchers said these amacrine cells provide “the missing component of an evolutionary ancient color vision circuit capable of setting the circadian clock by encoding the spectral content of light.”

Patterson said so little is known about rare retinal circuitry that it was possible to find a new blue cone cell. She said there is a lot more to be discovered about how blue cone cells are projecting to other areas of the brain.

Journal Reference: Sara S.Patterson, James A.Kuchenbecker, James R.Anderson, Maureen Neitz, Jay Neitz. “A Color Vision Circuit for Non-Image-Forming Vision in the Primate Retina” Current Biology (DOI: [4]10.1016/j.cub.2020.01.040)

The entire article is available on [5]Science Direct.


[6]Original Submission

Discuss this story at:
https://soylentnews.org/comments.pl?sid=20/02/22/0338234

Links:
0. martyb - SoylentNews User

  1. Let there be 'circadian' light | Newsroom
  2. https://www.cell.com/current-biology/fulltext/S0960-9822(20)30084-1
  3. The science behind 'circadian' lights | Newsroom
  4. https://doi.org/10.1016/j.cub.2020.01.040
  5. A Color Vision Circuit for Non-Image-Forming Vision in the Primate Retina - ScienceDirect
  6. Let there be 'Circadian' Light: SoylentNews Submission

So many different takes on this... but I went and downloaded an Android app called Sfilter. I kept going through the color filters until I found the one that made my eyes the most comfortable. Does the screen look like crap? Well...yeah... but my eyes are much more comfy, blue light or no.