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Medicine

Excess Time Indoors May Explain Rising Myopia Rates 144

Nature reports that an unexpected factor may be behind a growing epidemic of nearsightedness: time spent indoors. From the article: Because the eye grows throughout childhood, myopia generally develops in school-age children and adolescents. About one-fifth of university-aged people in East Asia now have this extreme form of myopia, and half of them are expected to develop irreversible vision loss. This threat has prompted a rise in research to try to understand the causes of the disorder — and scientists are beginning to find answers. They are challenging old ideas that myopia is the domain of the bookish child and are instead coalescing around a new notion: that spending too long indoors is placing children at risk. “We're really trying to give this message now that children need to spend more time outside,” says Kathryn Rose, head of orthoptics at the University of Technology, Sydney.
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Excess Time Indoors May Explain Rising Myopia Rates

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  • by ls671 ( 1122017 ) on Saturday March 21, 2015 @05:13AM (#49307649) Homepage

    I work in a basement 200 feet under the ground and I know it feels good to get outside once in a while.

  • People with agoraphobia are so screwed.
    • by Anonymous Coward

      Agoraphobia is not a fear of the outdoors or open spaces. Agoraphobia is a fear of any place/situation not easily escaped from. If you watch anime and want a humorous take on it find "Anime de Wakaru Shinryounaika - EP06" where for the format and time it is covered pretty well. If you prefer something a bit more rigorous try http://www.nlm.nih.gov/medlineplus/ency/article/000923.htm or better still http://www.dsm5.org/Research/Documents/Wittchen_Agoraphobia.pdf

      BTW for your other replier, agoraphobes do seek

      • The widely-understood meaning of agoraphobia is fear of open spaces, and wikipedia says it's mostly that plus fear of crowds. I think you've cast your net a little too widely, as your definition seems to include claustrophobia.
  • by bargainsale ( 1038112 ) on Saturday March 21, 2015 @05:40AM (#49307715)
    "About one-fifth of university-aged people in East Asia now have this extreme form of myopia, and half of them are expected to develop irreversible vision loss. "

    It doesn't actually say what "this extreme form" is, exactly. Presumably cut out in editing and nobody noticed that this was left stranded. There was probably a reference to so-called "high myopia", which does indeed cause people typically in their teens to go from the ordinary fully-corrected-with-glasses myopia to being much more so, with potential "myopic degeneration" of the retina. It's a mystery why this only happens to some myopes.

    The figures are scaremongering. Although this has indeed been a notable public health problem for a good while - the government of Singapore has been concerned about it for over a decade - it is nonsense that 10% of student-age people will go blind from it.

    I'm an ophthalmologist. I specialise in diseases of the retina.
    • I don't think there's anything missing, although it doesn't name a specific "syndrome" or such:

      In severe cases, the deformation stretches and thins the inner parts of the eye, which increases the risk of retinal detachment, cataracts, glaucoma and even blindness. Because the eye grows throughout childhood, myopia generally develops in school-age children and adolescents. About one-fifth of university-aged people in East Asia now have this extreme form of myopia.

      I think the middle sentence makes it harder to connect the two outer sentences.

      • Actually, I've got an increased risk of retinal detachment, although my ophthalmologists never mentioned increased risk of cataracts or glaucoma. I function normally with rather thick glasses, and would find it very difficult to function without them. No big deal, really, but it annoys me now and then.

    • by jpapon ( 1877296 ) on Saturday March 21, 2015 @07:13AM (#49307855) Journal
      From TFA:

      In Seoul, a whopping 96.5% of 19-year-old men are short-sighted.

      Say what you want about fear-mongering, that's a pretty crazy statistic. Sounds like I should invest in some Korean laser correction company.

      • By what definition of short sighted? Less than perfect vision?
        Technically you are short sighted when you do not have perfect vision, nor are far sighted. Its not hard to trick.

        • Considering only the myopia-hyperopia scale, myopia means only being able to focus at points closer than infinity. One weakness in the article is failing to give a number for the borderline of severe myopia, e.g. 10 diopters or whatever.
    • by Reziac ( 43301 ) *

      I'm a pro dog trainer, specifically retrievers, which need to have good distance vision. I've noticed that if puppies around weaning age don't have a long line of sight available, they never really learn to see distance later on, either. (Incidentally, there once was a bloodline that was infamous for myopia, so there is an inherited component too. Those dogs are not improved by environment.)

      I recall a study some years back that found if babies sleep in a lighted room, they are likely to become myopic.

      I'm th

  • Use it or lose it (Score:4, Insightful)

    by PSVMOrnot ( 885854 ) on Saturday March 21, 2015 @06:13AM (#49307763)

    So, as with many of the bodies abilities; it's just a case of use that distance vision, or lose it when your eyes adapt to shorter ranges.

    Just like muscle strength, flexibility, cognitive function, etc.

    • by Anonymous Coward

      That is exactly the PROBLEM though, they ARE using it, way too much.
      Focusing requires more effort that looking at far away things.

      Reading, being inside, watching TV, videogames, anything near you done long periods, all seriously damaging to your vision.

      Focusing too much on nearby things is causing you to tone the muscles in said eyes, which leaves their rest state at a larger size, which ends up being a size capable of shifting your max focal point closer and closer the more toned it gets.
      This can happen tw

      • Oddly enough, blue-only light is a solution

        Strange, isn't it? I thought it was new-age BS when I read that blue light tends to cure myopia in Linda Clark's The Ancient Art of Color Therapy (1981). 20 months ago I painted my house deep sky blue, and noticed after that staring at a blue wall for several hours, my vision was noticeably better. I'm over 60; this was a surprising result. I wonder what part of the eye is changing.

    • Re:Use it or lose it (Score:4, Informative)

      by dasunt ( 249686 ) on Saturday March 21, 2015 @11:09AM (#49308671)

      So, as with many of the bodies abilities; it's just a case of use that distance vision, or lose it when your eyes adapt to shorter ranges.

      Except according to the article, that isn't the mechanism. It's the intensity of light that causes the body to prevent myopia due to changes in dopamine levels.

      Not only that, but in animal studies, if chicks were given a drug that inhibited dopamine's effects on the eyes, they'd develop myopia in the same conditions that the control chicks would not.

      So it's not "use it or lose it". It's "you need bright light".

  • by gringer ( 252588 ) on Saturday March 21, 2015 @06:19AM (#49307773)

    For those who didn't pick up on the bit in the summary, this is not due to close work, it's most likely due to exposure to bright light:

    But time engaged in indoor sports had no such protective association; and time outdoors did, whether children had played sports, attended picnics or simply read on the beach. And children who spent more time outside were not necessarily spending less time with books, screens and close work.... Close work might still have some effect, but what seemed to matter most was the eye's exposure to bright light.

    If this is the case, then what we should do to reduce the myopia problem is to use brighter lights inside.

    • Internal lighting is so much dimmer than light outside that this is probably not practical.

      The eye is very accomodating and will adapt to great extremes of light.

      This is credible as a mechanism. Optical acuity is improved by having a smaller pupil (this is why squinting to improve your vision is a thing - you're sacrificing light collection to reduce the number of stray unfocussed lightpaths entering your pupil). Therefore if you don't get enough light, your iris muscles will atrophy making your pupil wider

    • by PPH ( 736903 )

      This seems to be counterintuitive. Bright lights cause pupils to contract, increasing the depth of field and reducing the work that the ciliary (focusing) muscles have to do. The more work these muscles have to do, the stronger they get and the more they flex the lens, keeping it pliable.

      In times past, the best test for visual acuity was the ability to resolve double stars.

      • Even though a tiny iris opening means not having to do as much work to achieve acceptable focus, that's not how the body works. Regardless of light level, eyes try to reach perfect focus, which does not change with different light levels.

        It could easily be argued that overworking the eyes' muscles by trying to focus in dim light would lead to exhaustion or even spasm - see the hypothesis of William Bates. I don't accept that argument, but it has been seriously proposed.

    • by unimacs ( 597299 )
      Average indoor light levels at an office or school are about 500 lux. Outdoors on a cloudy day is about 10,000. You think we consume a lot of energy now, just try illuminating all the classrooms to 10,000 lux.

      Just get the kids outside. There are so many other benefits.
      • by gringer ( 252588 )

        Replace a room lit with incandescent lights with LEDs consuming a similar amount of power, and that's getting close to this level of light (5,000 lux vs 10,000 lux using today's technology). So it's not too much extra energy required to get to 10,000 lux.

        • by unimacs ( 597299 )
          An office or school room is typically lit with fluorescent lighting which consumes more energy than LEDs but much less than incandescents. The problem with lighting whole rooms with LEDs is that the light tends to be more focused and directional. They are getting better but remember we are talking about going from 500 lux to 10,000. That would be a challenge to do with LEDs.

          You'd need a lot more fixtures. It would not only require more power but the cost of retrofitting a school would be very high. Thoug
  • by ciaran2014 ( 3815793 ) on Saturday March 21, 2015 @06:23AM (#49307779) Homepage

    A few years ago I worked at a desk facing a wall and I got the feeling that it wasn't good for my eyes that they never focussed on anything more than a metre away, so I put a mirror on the wall and I think this has helped my eyes.

    I tilted the mirror up a little so I could stare into it whenever I wanted without making eye contact with others.

    • by hcs_$reboot ( 1536101 ) on Saturday March 21, 2015 @06:46AM (#49307805)
      A few years ago I worked at a barn facing a meadow and I got the feeling that it wasn't good for my eyes that they never focussed on anything fewer than a metre away, so I put a wall and I think this has helped my eyes.
  • FTFA :

    They are challenging old ideas that myopia is the domain of the bookish child and are instead coalescing around a new notion: that spending too long indoors is placing children at risk.

    Doesn't that amount to the same thing? Not spending much time on distance focussing?

    • FTFA :

      They are challenging old ideas that myopia is the domain of the bookish child and are instead coalescing around a new notion: that spending too long indoors is placing children at risk.

      Doesn't that amount to the same thing? Not spending much time on distance focussing?

      Yeah, I laughed when I saw that. Someone's pretty clueless.

    • by afgam28 ( 48611 )

      Not enough time spent distance focusing is possibly a cause of myopia, but the article presents an alternative hypothesis: that it is the reduced level of light indoors that is the problem.

    • by sjames ( 1099 )

      If you had kept reading, you would have seen that the new theory (backed by experimental evidence) is that it's the light level that makes the difference.

  • by Applehu Akbar ( 2968043 ) on Saturday March 21, 2015 @08:24AM (#49308055)

    Can we develop an e-book reader that presents a virtual image that must be focused on as though it were at a distance? Let a cohort of Asian kids go through childhood reading from this device and see what happens to their vision.

  • Stop it (Score:3, Informative)

    by itchybrain ( 2538928 ) * on Saturday March 21, 2015 @08:39AM (#49308093)
    Stop masturbating, people.
  • by Dr_Barnowl ( 709838 ) on Saturday March 21, 2015 @09:18AM (#49308209)

    I started noticing this when I was revising for A-Levels. (17-18)

    My distance vision would start to fuzz after hours on the books, and be restored by a long walk.

    It's pretty much done the same thing ever since.

    One thing I do is make sure to focus on distant objects while looking out of the window a few times an hour.

    The other thing that helps is wearing +1D reading glasses (just cheap ones from the supermarket). These are designed for oldies who can't focus on close objects anymore - so they move the focal point of close up material much further away. A foot or two away, my monitor is basicaly at infinity, which stops/reverses the atrophy of my distance vision.

    Focussing is mediate by muscles! Like any others, use them, or lose them.

    • 1 meter away, actually. +1D is 1 diopter; a diopter is an inverse meter.

      There are those who state that muscles are used only to close-focus, changing the shape of the lens and the whole eyeball, and that distance focusing is a state of relaxation. Others claim that muscles are also used for far-focus. If the first group is correct, no amount of eye-exercise will help the myopic.

  • So they can breath polluted air. Soon to become even more polluted due to deregulation in the US and lack of regulation elsewhere.

  • stop the tech the test ideas and have recess come back in schools.

  • Or at least not wear their "normal" prescription when reading. I know for sure what happened to me. I spent plenty of time outside but I read a lot of books too. I acquired nearsightedness by about 5th grade, so of course they gave me corrective lenses to restore 20/20 vision, i.e., perfect focus at something 20 feet away. That meant that for reading, my eyes had to focus even closer than they would otherwise, in order to compensate for the glasses trying to focus farther away, so I got even more nearsi
  • Ask the kids to focus on owning their own home some day.
    It'll cure 'em in minutes.

  • I grew up in the 50s and 60s, and I spent most of my time (when not in school) outdoors. We rarely went indoors during summer break, in fact they had to make us come back in during thunderstorms. I was nearsighted by the time I was in 4th grade and had glasses shortly after that.

    As an adult I've worked outside for the past 39 years. Still nearsighted and still wear glasses.

    What caused my bad vision? Certainly not too much time spent indoors, right?
  • I've been spending all this time indoors, and now my eyesight is around -9.00 diopters. (yes, true, and yes, that's pretty high powered myopia right there).

    Of course, as a child of the '60s, I spent plenty of time outside. And it was always baffling that my eyes where so bad, because none of my parents had this bad of eyesight. Both could actually carry on without prescription lenses, unlike my daily life. Turn out, both carried the recessive gene for it, and those are the ones that I inherited.

    I needed

  • I call "bullshit", as would my opthamologist.

    Most childhood-developing myopia is a result of growth factors (The eyesocket changes size and shape as you get older and the eyeball can end up with distorted curves. Only 1-2mm variation is enough to cause issues). The predominant cause is genetic, not environmental.

    Anything beyond 3 meters is close enough to "infinity" as makes no odds, so "indoors" would have to be extremely claustrophobic to even factor into this.

    Bookish children tend to be myopic for the si

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