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Science

Declining Eyesight Can Be Improved By Looking At Red Light, Pilot Study Says (cnn.com) 137

swell shares the findings from a small pilot study that suggests a few minutes of looking into a deep red light could have a dramatic effect on preventing eyesight decline as we age. CNN reports: Researchers recruited 12 men and 12 women, whose ages ranged from 28 to 72. Each participant was given a small handheld flashlight that emitted a red light with a wavelength of 670 nanometers. That wavelength is toward the long end of the visible spectrum, and just short of an infrared wavelength, which tends to be invisible to the human eye. They spent three minutes each day looking into the light over a period of two weeks. The lights work on both cones and rods in the eye. Cones are photo receptor cells that detect color and work best in well-lit situations. Rods, which are much more plentiful, are retina cells that specialize in helping us see in dim light, according to the American Academy of Ophthalmology.

Researchers measured the cone function in subjects' eyes by having them identify colored letters with low contrast. And they measured their eyes' rod sensitivity by asking them to detect light signals in the dark. There was a 14% improvement in the ability to see colors, or cone color contrast sensitivity, for the entire two dozen participants. Improvement, however, was most significant in study participants over age 40. For those ages, cone color contrast sensitivity rose by 20% over the course of the study. That age bracket also saw significant increases in rod threshold, which corresponds to the ability to see in low light. Study participants under 40 also experienced some improvement, but didn't see the same jump as older subjects. Younger eyes haven't declined as much as older eyes.

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Declining Eyesight Can Be Improved By Looking At Red Light, Pilot Study Says

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  • Caution (Score:5, Funny)

    by Ogive17 ( 691899 ) on Tuesday June 30, 2020 @08:16PM (#60248716)
    Do not look into laser with remaining eye.
    • No, just look at a background with 255,0,0 (670 nm) or paint your bedroom ceiling in that color.

      • by skids ( 119237 )

        Display LEDs these days generally tend to be peak emission in the 630nm range, though they have plenty of side-band down into 670nm (and if you close your eyelids that'll filter more of the redder light out, but then you need a brighter source.) Old MM SX telcom LEDs are 850nm which is technically out of the range of human vision but you can still see them via their sideband (not recommended to more than glance at them, since they can be coherent.)

        Not that I'm sure it matters for this purpose, I doubt the

  • ...to a local beauty spot? (that's for the UK audience)
  • amazon.com red flashlight

  • by Fly Swatter ( 30498 ) on Tuesday June 30, 2020 @08:39PM (#60248786) Homepage
    Because it sure seems that way, at least for night vision and circadian rhythms. Btw why is every light in my car stupidly blue?
    • It may have been stupid of you to buy a car full of blue lights. But it was smart of them to make all the lights blue because that is the fashion right now.

      However, blue light tends to keep people awake, so maybe it's not bad for you to have made that particular purchase decision.

    • One possible reason (Score:5, Informative)

      by Presence Eternal ( 56763 ) on Tuesday June 30, 2020 @08:49PM (#60248806)

      Bright blue led lights were an enormous breakthrough. Nobel prize winning level stuff. They where the last barrier standing in the way of white led lighting. Since they were the newest thing, that was probably enough to make them the coolest thing. Red led lights on the other hand were associated with blinkenlights computers on 1970's era television shows.

      https://en.wikipedia.org/wiki/... [wikipedia.org]
      https://www.popsci.com/article... [popsci.com]
      https://www.nobelprize.org/pri... [nobelprize.org]

    • My old Saab,( because they were an aircraft company first), used only faint green or red in the dash, it was a very visually comfy car to drive at night.
      If you ever look at a military aircraft cockpit, all backlights are red or green as they do not fuck night vision.
      Ohhh the pilots would bitch when I was in the AF and someone repaired a console LRU lamp with a white bulb, imagine trying to fly at night and everything is dull red except for ONE section of bright white!

    • Now I'm missing my '85 Mustang. The entire dash was back-lit red. When I first got it, I thought it was evil looking but I appreciated that it wouldn't destroy my night vision when I drove out into the sticks to look at the stars.

      I don't miss the flaky carb or the idiot temperature gauge though. The latter is probably why the car only got 130k, despite my religiously changing the oil. It took me too long to realize that "high normal" was really over-heating.

    • by AmiMoJo ( 196126 )

      It's only anecdotal but I can confirm that I feel a lot less tired from looking at screens if I wear blue light cutting glasses. For some reason they seem to be more effective than just adjusting the colour temperature of the monitor.

    • Btw why is every light in my car stupidly blue?

      Probably because you bought it at a time when blue was in vogue. No doubt there's many other stylised choices that are prominent in your car as well, not just the colour of the lights.

    • Comment removed based on user account deletion
    • I have a 99 Honda with red instrument lights. I put in a new radio with blue lighting, and covered the face plate with black plastic. Annoying!
    • My last two cars have had red or amber dash lighting, and so will my next car. Really is easier on your eyes. For a while I was using a USB stick with a blue LED for my music, even though the usb port was very low on the dash that tiny blue light was super distracting.
  • So the question is (Score:4, Interesting)

    by bobstreo ( 1320787 ) on Tuesday June 30, 2020 @08:53PM (#60248816)

    is some specific wavelenghts of light can be beneficial for eyesight, are there also wavelengths that are harmful? (I'm guessing blue is right up there)

    • by rHBa ( 976986 )
      Anything at the far ends of the spectrum probably isn't great (UV/IR)
    • Actually, current studies seem to show that blue light is very important for proper development of the eye in children. China is putting a lot of effort into research in this area: they had an entire generation (or two?) of children with massive near-sightedness. Now they require all kids to play outdoors a minimum amount of time, and the reason this works is apparently the full-spectrum (and specifically blue) light, which helps the eyes to develop their proper shape.

    • by gweihir ( 88907 )

      Blue is known to be harmful, but severity of effect is not quite clear at this time. It may be a good idea to set a warmer monitor color temp when you are older. I did that and after a few hours you do not notice anymore.

    • by AmiMoJo ( 196126 )

      Ultraviolet light can be harmful. You shouldn't look at UV sterilizing lights or at some kinds of welding equipment that produce it or you end up with the feeling of having grit in your eye. Sometimes it goes away if it's not too bad but it can cause permanent damage.

      Other than that the only real danger is from extremely bright lights, i.e. lasers.

      Blue light is thought to affect your body in other ways though, specifically messing up your natural daily rhythm. There is debate over how much effect it has but

  • I happen to have a few 670nm LEDs here at my workbench and I want to try them out while I can still see them!

  • by iggymanz ( 596061 ) on Tuesday June 30, 2020 @09:15PM (#60248858)

    Outdoors has more red light than what they're looking at. Sure, more orange, yellow, green and blue too. But is this just a therapy for all of us who are indoors too much during the day?

  • by ArhcAngel ( 247594 ) on Tuesday June 30, 2020 @09:16PM (#60248860)
    Are they only testing Pilots? Is there a reason bankers or welders weren't included?
  • and on the flip side, staring at those awful mega-bright blue LEDs they put in "modern" electronics, will make you go blind. And buy cell phones.

    • by 93 Escort Wagon ( 326346 ) on Tuesday June 30, 2020 @09:26PM (#60248904)

      That’s NOT what my mom told me would make me go blind!

    • I've taped over all the blue LEDs I own. It's the only thing to do. And they're so bright you can still see them through several layers of tape.

      • Maybe the blue LEDs can kill viruses in the air? COVID19 puts LEDs in a whole new light.
      • I hate blue LEDs- I find them painfully bright at night. Like you, I tape them over (yes, several layers) or in some cases I've painted them with translucent stained glass paint to turn them red.

        In the old old old days I'd unsolder them and replace them with red LEDs but now everything is SMD and it's too much trouble.

        And this is all because years ago some jackass decided that red LEDs should only indicate a 'trouble or error condition'. That 'standard' was formally adopted by all the electronics manufactu

  • Is that the bloom or the veg light?
  • I guess I will need to head to the red light district every day. Need to take care of my eyesight.
  • Can an OLED iPhone display this wavelength?

    • by caseih ( 160668 )

      Probably not. Aren't RGB color sources only capable of displaying spectral colors, not real colors?

  • Comment removed based on user account deletion
  • Did not read TFA but curious how did then know to set up this experiment?
    Obviously they wanted to prove or disproof what they already suspect, no?

  • No control group (Score:5, Insightful)

    by bradley13 ( 1118935 ) on Wednesday July 01, 2020 @02:41AM (#60249498) Homepage

    This pilot study lacked a control group of patients who could have been exposed to a dummy light that emitted, he noted.

    This invalidates the study completely. For all we know, the people got better at discriminating colors, because the study had them practicing this skill, or because it was a Tuesday, or because Mars was in conjunction, or...

    Seriously, WTF is any scientist doing, carrying out a study without a control group?

    • Agreed.

      At an improvement of only 14%-20% can one explain an increase with a) an increased willingness by the participants to commit to the tests as there will always be moments where someone will try to get past it quickly and b) a more trained ability to recognise letters on low contrast and light signals.

      Then it also depends if they've used the same font and signals, which one can also train to better recognise, and if they've been shown different letters, words and signals each time, or if these were alw

    • Re:No control group (Score:5, Interesting)

      by Mr. Barky ( 152560 ) on Wednesday July 01, 2020 @04:41AM (#60249670)

      A study without a control group can be cheaper to run and hence you can look at more things with the same budget. Once an interesting correlation is found (such as this) it shows that further study might be interesting. To really demonstrate that it is cause/effect you need to do a higher quality study with control groups etc. It isn't necessarily a waste to do a lower threshold study - if they find no correlation, they just move on to their next idea.

      Of course, if they present the study as more than it is, that is a problem. I have no idea if that happened (or if the write-up implied things the author of the study did not - something that quite often happens).

      • No, that's just a waste of money. They could have bought some pizzas, have an interesting conversation and then decided to do it right.

        Doing it wrong, to then do it right, isn't a reason to keep doing it wrong. You do it wrong, you learn from the failure, and then you stop doing it wrong. You don't keep it up, because it was interesting.

        Or ask yourself, what if they hadn't found a correlation? Would this have sufficed to exclude any existence of a correlation and not to do further studies? No, it doesn't! A

    • by njvack ( 646524 )

      No, it doesn't invalidate the study. It just means "don't go buying a red flashlight because of this study."

      Well-designed randomized controlled studies are difficult and expensive to design and run. If the researchers had found that after this pilot study, people hadn't improved, it would have told them something important: It's probably not worth it to plan and run the big expensive study. Randomized controlled trials are very important, but they aren't the only important thing in clinical research.

      If you'

      • This is just more of the same nonsense... Yes, it does invalidate it, because your test doesn't show why there was an improvement. This could be anything from a false measurement, to psychological effects or there being an actual positive effect.

        They didn't just decide to shine a red light into 24 people's eyes out of mere curiosity. Or how would this work? You have an idea, you pick a colour, perhaps green, and start shining light into people's ears, no wait, lets shine it into their eyes and make it a red

    • Seems like this preliminary study was the cheapest way to test if this hypothesis could possibly be true.

      Preliminary results in hand, on a topic of import to many grant organizations, the researchers shouldn't have much trouble getting the funding to find out whether this effect truly exists with larger sample sizes and controls and over longer periods.

      • Seems like this preliminary study was the cheapest way to test if this hypothesis could possibly be true.

        Yes, it may seem like it, but it's wrong.

        Say you want to bring back blood letting. Your hypothesis is that when it has success then the number of your patients visiting you must go down. So you perform it on your patients whenever they come in sick and you monitor how many of them return. Over time does the number of your patience go done. You can now use the test result to ask for funding in order to do more research, because your test has shown the improvement you were looking for and it has reassured you

  • See you all in Amsterdam!

  • I just keep getting angrier and angrier. Maybe I'm just bullish about the market.
  • by ibirman ( 176167 ) on Wednesday July 01, 2020 @09:00AM (#60250106) Homepage

    I looked up the hex color, it's #ff0000, so I created a website, https://670nm.net where you can look at the color on your screen. Enjoy!

    • I went there and there wasn't enough advertising all over the page. Furthermore, the site wasn't nearly web 2.0 enough. Not one CSS popover to ask me to sign up for email updates, and it didn't even obscure 70% of the window with a cookie policy. Where's the ever floating navbar? The second, third, or fourth bars with special media links, social reactions, etc? And why couldn't you at least load ab autoplaying video of someone reading the text of this story very slowly interspersed with color commentary? He

    • by jmkaza ( 173878 )

      I tired this (mid forties, eyesight started degrading a year ago, willing to try anything, bookmarked). One interesting thing I noticed is that when I went to the sight, it was bright red. As I stared, it seems to fade to orange. Eyes are definitely doing something!

    • Thank you - quite interesting.

  • ... does that geezer have to sit through before he sees the green and drives on?

  • Does it improve my ability to read small text? Will it help improve my ability to see near or far?

    There are great solutions for low light situations, flashlights are not new. What I need is improved vision, an improved total range of vision - not a compromise between near or far or better low light vision.

  • Two of my 3 sons are currently doing "light therapy" (among a number of other things including eye excercises), which involves:
    * for one child, looking at a red light for 10m and a green light for 10m, daily
    * for the other, looking at a green light for 20m, daily

    This is treatment by a well-respected opthalmologist for heridirory conditions (which if untreated can lead to lack of depth perception due to the brain rejecting one eye).

    Since I am finding it more difficult to read small text in poor lighting (eve

  • This sounds implausible. I'll believe it when I see it.

Solutions are obvious if one only has the optical power to observe them over the horizon. -- K.A. Arsdall

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