[HN Gopher] Blue-light filtering spectacles probably make no dif...
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       Blue-light filtering spectacles probably make no difference to
       sleep quality
        
       Author : clumsysmurf
       Score  : 43 points
       Date   : 2023-08-18 18:35 UTC (4 hours ago)
        
 (HTM) web link (medicalxpress.com)
 (TXT) w3m dump (medicalxpress.com)
        
       | treprinum wrote:
       | Without Gunnars I can look at a display for 5 hours before eye
       | strain sets in, with Gunnars I can look for 12 hours. So either
       | they used shoddy lens/filters or I am just special somehow.
        
         | aljgz wrote:
         | Placebo effect, maybe?
        
           | anon84873628 wrote:
           | Maybe. We also need to know whether they have a non-tinted
           | but still "computer glasses" control. I think computer
           | glasses have other tweaks specifically for viewing screens.
        
         | anon84873628 wrote:
         | Well Gunnars are actually amber tinted. At the end of TFA it
         | says, "Filtering out higher levels of blue light would require
         | the lenses to have an obvious amber tint, which would have a
         | substantial effect on color perception."
         | 
         | This implies that they studied lenses that aren't tinted, which
         | obviously can't be that effective...
        
           | karmakaze wrote:
           | > which would have a substantial effect on color perception.
           | 
           | Our vision system is pretty good at compensating for white
           | balance. What I've noticed is with reduced higher
           | wavelengths, my visual acuity drops substantially.
           | 
           | These glasses may not improve sleep quality, but my
           | experience is that it increases sleep quantity as looking at
           | a white display keeps me awake longer like it's still
           | daylight hours, where as with reduced blues my body tends to
           | think it's near bedtime and I do tire and hit the sack
           | sooner.
        
       | ChrisArchitect wrote:
       | Not sure about the effectiveness in "lens-form" but the dimming
       | that apps like f.lux and on mobile definitely feel like they help
       | turn down the harshness of bright displays in dark rooms. I have
       | sworn by those apps for like 20 years. It's just like using dark
       | mode. "Easier on the eyes". Less strain on the muscles.
        
         | gowld wrote:
         | Phone/computer apps actually reduce the blue substantially and
         | visible, unlike the nearly-transparent lenses in the article.
        
       | walterbell wrote:
       | https://gembared.com/blogs/musings/the-best-daytime-white-li...
       | 
       |  _> Do white LEDs really exist that are low in blue light,
       | balanced with red, low flicker, and low EMF? ... especially for
       | LEDs, we want lower Kelvin which helps minimize the blue light
       | that many people have had issues with LEDs in the past. For this
       | review we mostly selected 2700K LEDs as it usually has a natural
       | feeling balanced spectrum that is lower in Blue light. But for
       | office areas during the daytime the 3000K versions might be
       | better._
        
       | Stratoscope wrote:
       | A couple of months ago we had some neighbors over, a couple and
       | their two sons, for an early dinner in the back yard.
       | 
       | They just got back from a family vacation, and one of the sons
       | showed me some photos he took on his iPhone.
       | 
       | The photos were in focus and well composed, but everything had a
       | strong orange cast. They almost reminded me of Kodacolor
       | negatives [1] but of course they were positives, not negatives,
       | just very orange.
       | 
       | I meant to ask if he was using some artistic filter or manual
       | white balance, but I figured "he's having fun showing his
       | pictures, let him run with it."
       | 
       | Then the other son showed some photos on his phone, and they were
       | orange too!
       | 
       | It wasn't until later when I got a glimpse of their mom's phone
       | that I realized what the problem was. She didn't have a photo on
       | the screen, just some text or a web page that would have a white
       | background.
       | 
       | You guessed it, that was orange too. And I finally realized they
       | all had Apple's Night Shift turned on.
       | 
       | Well, if nothing else, this gives me a good excuse to get
       | together with them again so I can see their photos as they were
       | meant to be seen. :-)
       | 
       | [1]
       | https://web.archive.org/web/20101128030127/http://photo.net/...
        
       | gitpusher wrote:
       | That may be true. But for people like me who have good eyesight
       | and don't need glasses, they provide a socially acceptable way to
       | wear cool-looking glasses in the workplace.
        
       | jrockway wrote:
       | Yeah, none of these glasses filter out anything close to "all"
       | blue light, because nobody would buy them if they only had
       | red+green color vision.
       | 
       | As an aside, there was some time in the recent past where blue
       | antireflective coatings on eyeglasses were popular. I actually
       | had to make a special request for the old purple/green coating
       | for a few years, because the blue reflections were so distracting
       | while working in an office with overhead fluorescent lights. Many
       | years have passed since that trend and modern coatings seem more
       | blue-ish than purple/green, but they aren't distracting at all.
       | I'm actually shocked how little light modern lenses reflect at
       | all.
        
         | anon84873628 wrote:
         | I didn't understand how people could claim they have "blue
         | light blocking glasses" with clear lenses. I can literally see
         | the blue light coming through it!
         | 
         | I think Gunnars was early to the market and they actually have
         | amber tint. Before that I would buy amber tinted safety glasses
         | meant for working with lasers. I still take these on trips if
         | I'm staying somewhere unfamiliar... You don't know if the place
         | is going to have hideous harsh blue-white LEDs. Fortunately
         | most places have figured out the need for comfortable warm
         | lighting. All the computer operating systems have a built-in
         | night mode too. I stopped short of putting an amber film over
         | the Kindle...
        
           | EA-3167 wrote:
           | I have some blue-light blockers which I use only in bed, when
           | reading before going to sleep. They are bulky with 'side
           | boards' to block light, and they turn everything into a sort
           | of orange, undifferentiated hellscape.
           | 
           | The upside is that they seem to work, the downside is that it
           | really only works if you're at a point in your day where
           | you're ONLY looking at text.
        
       | GoToRO wrote:
       | Do these glasses prevent you from fully waking up? Indoors
       | environment wirh little light, also block the blue light and you
       | can be sleepy all day.
        
       | reaperducer wrote:
       | Yesterday's New York Times article about this:
       | https://www.nytimes.com/2023/08/17/well/live/blue-light-glas...
        
       | mrguyorama wrote:
       | One of these "Blue blocker" coatings was $10 to add to my $400
       | (sticker price "$1400" because luxotica is a fucking racket)
       | glasses. I knew there was little real research on such a thing,
       | but in the moment I guess I didn't really care about wasting a
       | couple bucks. Very unlike me really.
       | 
       | I can't actually tell that there's anything different about them.
        
         | foobarian wrote:
         | I've been getting increasingly fed up with the US optical
         | services and the slow feedback loop. For the price of a pair of
         | glasses I could get this [1] and just choose my prescription
         | however I like!
         | 
         | [1] https://www.amazon.com/UCanSee-Optical-Trial-Metal-
         | Aluminum/...
        
       | marvindanig wrote:
       | Have you ever noticed that B(lue) and G(reen) are the center most
       | frequencies of the visible spectrum--VIBGYOR? If the human eye is
       | naturally adapted for blue skies and green forests, how could the
       | blue wavelength ever be harmful to our eyes? Those are the
       | healthiest frequencies our eyes "consume!"
       | 
       | So much bullshit is marketed these days that it is impossible to
       | sleep well.
        
         | Symmetry wrote:
         | During most of the evolution of our genus bright blue or green
         | light meant it was daytime and hence time to be awake. But the
         | red light from fires would often be present when our ancestors
         | were sleeping. It isn't that you should avoid bright blue or
         | green light in general, it's that you should avoid it for maybe
         | an hour or so before you go to bed until when you want to wake
         | up.
        
           | nomel wrote:
           | > But the red light from fires would often be present when
           | our ancestors were sleeping.
           | 
           | I don't believe this is related. I believe it's simply that
           | blue is the best/easiest/earliest color. The circadian rhythm
           | is ancient, used by bacteria, plants, and mammals [1], long
           | before humans had fire. Blue is most energetic, and is all
           | that can be seen in the depths of the ocean, where life
           | mostly likely originated.
           | 
           | [1]
           | https://schaechter.asmblog.org/schaechter/2023/04/sensing-
           | bl...
        
           | croes wrote:
           | We have way better receptors for dark and bright, so for that
           | color reception isn't necessary.
        
         | mgiampapa wrote:
         | Where did you go to school? It's ROYGBIV you monster!
        
           | jayd16 wrote:
           | Endianness strikes again.
        
         | talldrinkofwhat wrote:
         | Circadian rhythms are primary drivers for various hormones in
         | your body (e.g. melatonin, body temps, cortisol levels). These
         | rhythms are tightly tied to external/evolutionary triggers.
         | Yours body resets its internal clock* based on external cues,
         | the strongest of which are eating and exposure to daylight.
         | Since we don't have little clocks saying it's 6:05 in our
         | heads, the body uses blue light hitting the retinas as a proxy.
         | It's the knock-on-effects of having misaligned cortisol levels
         | (which further induce lack of sleep / stress) that are the
         | problem, not the blue light.
         | 
         | *The natural rhythm of each individual differs, hence the
         | cave/space experiments where some people naturally fall into a
         | ~25h cycle [due to lack of external cues]).
        
         | steve1977 wrote:
         | Well the theory behind it doesn't say ,,blue is unhealthy or
         | harmful" but ,,blue is daytime".
         | 
         | Hence the idea to filter out blue at times when there is no
         | blue sky in nature (aka at night).
        
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       (page generated 2023-08-18 23:02 UTC)