
Increased rates of myopia linked to reduced time outside, studies suggest (2015) - oska
https://www.nature.com/news/the-myopia-boom-1.17120
======
dxbydt
Its a very well studied dataset in (graduate) Stats. So many contingency
tables where you correlate onset of myopia - myopia vs Asian/non-Asian, myopia
verus Male/Female, with/without computer, w/wo smartphone, w/wo outdoor time,
w/wo myopic parents, on & on.

If you know how to run a ChiSq, you can look at some 2x2 tables here. You can
convince yourself with 1 line of R.

[https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1771677/](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1771677/)

Or if you want someone else to run the analysis & just skip to the
interpretation of results, try this -
[http://astro1.panet.utoledo.edu/~terencezl/projects/myopia.h...](http://astro1.panet.utoledo.edu/~terencezl/projects/myopia.html)

But honestly, there's a ton of data on this subject. Conclusion is mostly the
same - if you spend more time outside, less likely to be myopic. That's the
one factor you can control. The others (being Asian or male or having myopic
parents etc) is luck of the draw.

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notkid
The other side of this problem is that more than one billion people around the
world can't afford glasses.

"More than a billion people around the world need eyeglasses but don’t have
them, researchers say, an affliction long overlooked on lists of public health
priorities. Some estimates put that figure closer to 2.5 billion people. They
include thousands of nearsighted Nigerian truck drivers who strain to see
pedestrians darting across the road and middle-aged coffee farmers in Bolivia
whose inability to see objects up close makes it hard to spot ripe beans for
harvest. Then there are the tens of millions of children like Shivam across
the world whose families cannot afford an eye exam or the prescription
eyeglasses that would help them excel in school."

[https://www.nytimes.com/2018/05/05/health/glasses-
developing...](https://www.nytimes.com/2018/05/05/health/glasses-developing-
world-global-health.html)

~~~
notkid
VisionSpring, a social venture, provides people glasses - which they say costs
them $4-5 each. They claim that uncorrected refractive error costs the global
economy an estimated $227 billion a year. [https://visionspring.org/why-
eyeglasses](https://visionspring.org/why-eyeglasses)

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littlestymaar
Related: myopia is one of the most common health problem that occurs to
prisoners.

~~~
epmaybe
Do we know if that myopia is caused while in prison, or if it is just picked
up while they are in prison. Because it would be very unusual to see myopic
changes from emmetropization (eye remodeling) occurring in adults.

~~~
littlestymaar
> Because it would be very unusual to see myopic changes from emmetropization
> (eye remodeling) occurring in adults.

What makes you think it's unusual?

~~~
epmaybe
So some background information is necessary to get everyone on the same page.
The optics of the eye are such that the lens and cornea focus light onto the
back of the eye, the retina. That focusing power can be inadequate or
overpowered depending on the axial length of the eye. You can imagine that you
would need a diverging lens to help focus light better in a longer (myopic, or
near-sighted) eye, and a converging light to help focus light better in a
shorter (hyperopic, or far-sighted) eye.

We know from several large scale studies that eye reaches its maximum axial
length by around age 13, and while the eye gets ever so slightly shorter
(hyperopic, rather than myopic) as you age, it's far outweighed by the effects
of presbyopia, whereby the lens of your eye becomes less elastic with age, and
thus is unable to focus up close. In effect, it makes you more farsighted, and
why people with myopia feel that their vision somewhat improves with age.

Sources (with references to the large scale studies, which unfortunately I
cannot currently access):
[https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4347057/](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4347057/)
[https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3843406/](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3843406/)

------
xedeon
This is a real issue in South Korea and many other Asian countries, where it's
prevalent.

In these countries, having a "fair/light" skin signifies social prestige.
Which is why most parents do not let their children go out to play and explore
while the sun is out.

This mentality is primarily rooted from imperial times, where tan skin was
associated with lower-class field or farm work. I personally experienced this,
growing up in SE Asia. The population is also bombarded with ads for skin
whitening soaps, creams, lotions, and even glutathione iv treatments.

It's a multibillion-dollar skin-whitening market in China, Malaysia, the
Philippines, Thailand and South Korea.

More on the subject:

 _The high prevalence of myopia in Korean children with influence of parental
refractive errors_ :

[https://journals.plos.org/plosone/article?id=10.1371/journal...](https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0207690)

2008 Article:

 _Outdoor Activity Reduces the Prevalence of Myopia in Children_ :

[https://www.sciencedirect.com/science/article/pii/S016164200...](https://www.sciencedirect.com/science/article/pii/S0161642007013644)

~~~
ChuckNorris89
In northern Europe it's the exact opposite. Youths go out of their way to get
tanned skin as is signifies social prestige on Instagram and IRL, as in you
can afford to go often on vacations in sunny places year round as opposed to
the poor wage slaves who are at their desks most of the year.

------
ak39
I had 2020 vision till 2012 (39 years old then). I am convinced that my myopia
onset was perceptibly accelerated with the purchase of my first "smart phone".
And the constant use of it: Whatsapp & twitter.

Can the damage be reversed?

~~~
tluyben2
Is there any proof/research that it is because of smartphones (screens?)? My
anecdote; I have had myopia since I was 7 (I am 45 now), 1 year _before_ my
first computer. Since then I have spent most my waking life behind screens and
my myopia has been getting less slowly since my first glasses. I now can see
quite well without glasses which I could not do 15+ years ago. Also, I should
be up for reading glasses soon, but I can read the tiniest fonts on the
tiniest screens without reading glasses (I need my normal glasses for that
though), which gives me a lot of real estate on small devices (for instance
working on a 4k remote desktop on my iPad pro 10inch; of course it does not
show the entire desktop at once (you scroll which makes it really a nice kind
of 'virtual desktop' system for me) but for me it's comfortable to read while
other people cannot even see what i'm doing as the fonts are really
minuscule). My eyes don't get tired though and never have on screens, even
when screens where crappy flickering low res CRT things (huge fonts of course,
compared to what I use now).

Maybe the spending time outside is more related to it as this article says; I
work almost exclusively outside. I abhor cold so I only spend my days in warm
climes where I work outside behind my computer/phone/tablet/... for the entire
day. When I have meetings, I try to get people to meet outside, which usually
works (most people like this far more than staying inside, even if it's
chilly, but not with freeze/rain/snow of course).

~~~
mywacaday
Pre smartphone days(1997) but when I was in college I had to get glasses to
see the whiteboard at the end of the first year spent looking at monitors and
a drafting board for large periods of the day. I spent my summers lifeguarding
on a beach so three months off staring hard into the distance from 10am to 7pm
6 days a week with hardly any screen time. When returning to college in
September I could see the board without glasses for the first 2-3 months but
then would revert to needing glasses. This cycle repeated itself for several
years but the time reverting to glasses got shorter each year. Sample size of
1, YMMV

~~~
EForEndeavour
Fascinating story, and I love the implication that you were lifeguarding
without glasses. I know from personal experience that bright sunlight improves
visual acuity (bright images, pupil constriction, and squinting all help), so
obviously you were able to do your job, but the mental image is pretty funny!

~~~
mywacaday
I actually never though of that and had a good laugh reading your comment. I
had to pass a medical with an eye test for the job so I presume I was safe.
Eyesight is a complicated thing, I have one eye much worse than the other, can
read the monitor fine with my right eye and not at all with my left eye. I can
use a monitor OK for an hour or two with no glasses but after that I get a
headache. My right eye defiantly compensates for my left.

------
MarkusWandel
I've needed glasses for myopia since my early teens. As the inevitable decline
in eye focusing ability set in (I'm now 52), I've taken to keeping a pair of
glasses with weakened prescription (-1, 1.25, 1.5 diopter all seem to work
equally well, just affects posture i.e. ideal distance to screen) near every
computer workstation I use. With cheap mail-order outfits like Zenni cost is
not an issue.

With these on, my eyes' comfortable (and nearly only remaining) "infinity
focus" is used to work at a computer. One wonders, if myopia is, in fact,
caused by long-term eye strain from excessive near focus time during
developing years, whether a disciplined approach of using normal reading
glasses designed for older folks, while doing all paper/computer work, might
help against developing myopia.

I'm aware of bifocals and contact lenses/laser surgery (with these, ordinary
cheap reading glasses would suffice) but I've always been most comfortable
just wearing normal eyeglasses, so switching to weakened glasses as necessary
works for me.

------
Mikeb85
I believe it. While I was in university, my eyes strained a lot to the point
where they'd start to tear uncontrollably for days on end, I'd get headaches
and my vision literally got worse. But every summer I'd spend weeks on end
outdoors, camping, hiking, etc... It got better, all the eye strain went away.
My mother used to have 20/20 vision, until a decade into her career as an
accountant (it could have been age, but eye problems aren't prevalent in her
family).

That's part of the reason I decided to do something outside of my degree path
(that and the fact economics is depressing AF). I still enjoy computers,
economics, all the things I studied, but working with my hands, stints in the
outdoors, not staring at a screen makes me happier (and healthier).

------
garyclarke27
Since I started walking our dog everyday on the beach, for health reasons,
I’ve noticed a definite improvement in my eyesight, I still don’t need glasses
age 56. I also remember when when I had a job in London that required
commuting on the tube my eyesight deteriorated quickly, when I switched jobs
and drove to work, it got better again, driving gives your eyes a good workout
because one constantly switches focus between far and close objects.

------
graeme
I moved to a ground floor place, and basically get no direct light. Sort of a
shock after years of a sunny place.

I have some studio lights around for recording. Would these benefit the eye
the way the sun does? I had considered using them while working for seasonal
affective disorder.

It's hard to be sure but my eyes feel a little weaker since moving in.

~~~
aeternum
I had a similar situation and did notice a positive improvement after getting
a super bright (5000 lumen) light. Could have been coincidence but I was
pleasantly surprised when my prescription decreased in strength.

I assumed using it at night would mess up my sleep, but it didn't.

------
fghkbvj
Isn't myopia beneficial? When eyes get adapted to screens, books maybe it's
bettter? I can see every single pixel on screens and it's very useful in daily
life. Far sight is useful only rarely - when driving, and when hiking in
mountains. And near sight worsens with age, maybe previous myopia slightly
prevents that.

On quora they agree [https://www.quora.com/What-are-the-benefits-being-short-
sigh...](https://www.quora.com/What-are-the-benefits-being-short-sighted-
myopia)

Thanks for reminding me about myopia, I will get glasses (if anything, just
for mountain views). One time I tried someone else's glasses and it was
wonderful, completely different world when being outside, extremely sharp, not
blurry.

~~~
frant-hartm
No, I have -4D and can't see a screen clearly from more than 25 cm.

~~~
unicornfinder
I have -5.50D and to be honest, whilst my vision is pretty poor I can
definitely tell that, when not wearing glasses, my close-up vision is better.
Not that it's actually helpful.

------
octosphere
I do an exercise each day where I try to (for at least 10 minutes) look at
very distant objects like the horizon or a tree in the distance. I do this
because it relaxes the eye especially if you work with screens all day (which
I do).

~~~
jolmg
I've heard the rule that it should be like at least 20 seconds every 20
minutes or so. Of course, it's all just heuristics, though.

~~~
lern_too_spel
None of these eye exercises have any benefit for myopia prevention. They might
reduce eyestrain, but that is not related to the article.

------
AlexDragusin
Next correlation: Increased risk of myopia linked to time spent on HN!

------
srbby
I can attest that I'm short sighted and the problem becomes much much worse if
I spend a lot of time in front of my computer.

Some days when I go out early in the morning I can see everything perfectly,
and other days I can't even read a number plate that is five metres away.

------
taneq
"Increased risk of wetness linked to reduced distance from water, studies
suggest."

Human bodies autocalibrate for their environment to a remarkable degree on
virtually every axis, moreso during childhood and adolescence and to a lesser
degree after reaching maturity. I can't fathom why anyone would doubt that
spending all of your time staring at nearby objects causes your eyes to adapt
to staring at nearby objects.

~~~
lern_too_spel
This article specifically says the near work hypothesis does not fit the data.

~~~
taneq
I'm not talking about the near-work hypothesis (ie. "too much close work
causes myopia"), but the related idea that "not enough far work causes
myopia."

And this perfectly fits the article's findings.

Anecdotally, a few of my friends are into sailing, in a 'crewing a large
sailing ship' sense, and apparently some have seen noticeable improvements to
their myopia after being out at sea for a couple of weeks and spending a lot
of time staring at the horizon.

