The Epidemics of Myopia - A good epidemiolgical study

I’ve been reading this good epidemiolgical study released in 2018.

It focuses on reforming the education system with a focus on Asia, essentially ground zero of this epidemic. Got a whole bunch of really good data.

published location:
Accepted PDF manuscript:

Obviously EMers will know a bunch more stuff than what’s covered in this paper but what I found particularly intersting is the idea of educational reform to prevent myopia. Many of these initiative have already started to take place WITH good results. Taiwan and China for example has already had promising reductions in myopia rates in test schools.

“These two school-based clinical trials (one in Guangzhou, China and the other in Kaohsiung, Taiwan) have shown that this approach can produce reductions of 25-50% in cases of incident myopia”

Their reccomendations to halt the myopia epidemic. Help the KEEEEEDDS. (As jake would say)
In a nutshell:

1. Reform of myopigenic education systems - i.e. asia is the worst with a focus on nearwork, repetitive study and memorisation with little to know active or outdoor focused education.
2. Increase time outdoors - self explanatory
3. Pharmacological and optic interventions - This bit is underwealming with a stardard ortho-k and atrophine drops stuff. But they do touch on myopic defocus which is where EM would step in.
4. A systematic school-based approach - A way to measure and monitor myopia prevention in schools for more scientific rigor.

Enjoy and thoughts!


The Education Department of China has put myopia prevention as one of its high priorities. We just need to see how that follows through to the undergoing education reforming…


Thanks for this. I am enjoying, and thoughts, if any relevant ones, will come later.

There must be a way to offer good education without ruining the eyes of children. That said, I would not exchange all that I have learned (and enjoyed) through reading for the absence of myopia. In my case it was not for lack of outdoor time and good sunlight, as we lived in South Africa.

It is good to hear that this is being taken seriously in China.


I did myself the favour of printing out the article and reading it in the excellent sunlight we have here today. It brings together a great deal of the other reading I have done since I started EM, and the only thing that really stuck out for me was the difference in accuracy between cycloplegic and non-cycloplegic measurement of myopia. I had met this concept when investigating pathological pseudomyopia, but I am now led to think that all tests of vision should include this, to prevent the danger of over-correction or any correction at all. I know it is time-consuming and unpleasant for the subject, but it may delay or avoid lens-induced myopia.

Sadly, it seems to confirm that increasing outdoor time may not be all that effective in either slowing the progression of myopia, or reversing it, as EM has led us to believe. But as outdoor time and exposure to good light have plenty of other health benefits, we should nevertheless expose ourselves to good doses.

But for low myops and parents whose kids get a prescription first time:
Section 6&7 + later, too: There is now consistent evidence that children who spend more time outdoors are less likely to be or become myopic. About 2 hours a day outdoors, out of school hours, in western countries, eliminates the additional risk associated with more near work.

I don’t think EM recommends outdoor time as in vs. out, closed vs. open. But it is the fact that if kids are indoors or in a study environment, they are more likely to engage in activities that require close up vision only. Going outdoors, playing ball games, cycling, beach time, flying kites, running around playing it, etc keeps the eyes’ full range of motion in use.
In my view, full ROM is superimportant below -2D

For children I agree, absolutely, but most of us on the forum are not children and have more than 2D of myopia.

I hear you. Kids treated with increased outdoor time for pseudo myopia will not become EM forum members, the members below -2D already spend less time here and more time outdoors. But I would not discard this part of the study completely, as in the next 3 years it will become relevant for those who are now between -2D and -5D. :wink:


this soundds interesting. Do you have any other readings on it?

Alot of these studies that talk about outdoor time don’t really flesh out their position on causality and correlation. I’ve read others that also plain get it wrong! Saying that ‘outdoor time prevents myopia’ inferring causation.

I think we can only assume a correlation between outdoor time and reducing myopia progression.

Nor do I think that EM claims that outdoor time slows the progression of myopia. The only message I get is “go outside because your more likely to use your distance vision + AF”. No?

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The first one I came across. It seems to be more relevant to children, but then the whole issue of the myopia epidemic starts with children now.

I may be mistaken in the impression I got on this. It seems that @varakari ‘tortured’ himself :wink: to get more outdoor time, thinking it would help, but apparently without much benefit. Sorry if I misread or misremember this. :smile:
For me it was paying attention to vision at all distances that seemed to work, and the biggest effect was with aggressive print pushing at screen distance from the start. As my lifestyle includes lots of outdoor time and distance vision, this may be the reason why I found little benefit from this - wihout actually paying close attention to what I could and could not see. My vision habits did not change with EM, simply my intention and degree of attention.

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Nice I’ll give it a read! Looks dense.

I think there is truth to that.

outdoor exercise produces at least temporary axial length reduction in myopes (I’m guessing wearing full correction):

but I’m curious as to what would happen immediately after outdoor exercise for myopes who wear an intermediate distance correction

uv light exposure also helps with myopia:

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Very interesting! This is also a great one. Both an animal and human trial in one!
This could be a big rabbit hole to go down. :upside_down_face:

As my previous comment, I think it helps being very specific about causaility. This study you’ve linked is proposing Violet Light exposure is important in reducing/controlling myopia. The outdoors, and therefore outdoor time means you’re more likely to get more VL, but outdoor time does not necessarily CAUSE myopia reduction.

I have only seen epidemiological/correlational studies linking outdoor time to myopia control. I’ve linked many of these in the wiki.

As we can’t do random double blind controlled trials on human vision, this is going to be the best we can do for the present. I am convinced that there are many factors in the development, control or reversal of myopia.

I would be just as interested in finding out why some people with the same vision habits and history as myopes fail to develop myopia. A lot of research has been done on the candidate genes and clusters of genes that predispose one to myopia, but it might be just as interesting to investigate which genes are ‘protective’ against the development of myopia. I think we all know emmetropes who get away with murder as far as vision is concerned.

A very distant prophecy - we will be able to edit out the predisposition to myopia in human embryos in the future. :astonished: But in the meantime we myopes plod on.


This is a can of worms I am scared to open.

My wife! Oh god!

Better the worms you know than the worms you don’t know. I have never doubted my genetic predisposition to myopia, as it was far too obvious. As it is a question of epigenetics most of the time, we can do something about it, although perhaps not as much as we hope for. For children we have much more wriggle room to prevent the genes from being switched on in the first place (pun intended).

My daughter, but as she how has presbyopia I am getting a small dose of revenge.

that’s interesting. makes me think of a hyperopic person that I know. she reads a ton and has been hyperopic all her life

And that includes several family members including a brother for me, which is why I think what predisposes us is not so much genes, or at least if they do it is less than other risk factors. In the same fashion I am more prone to getting a viral infection at some times but not at others, depending on my overall health. For instance, it is pretty common knowledge that pregnant women can suffer a decrease in visual acuity and that their vision goes back to normal later on. However, young girls going through puberty and hormonal changes are given glasses for myopia under -1D and told to wear them all the time.
Not saying puberty causes myopia, of course. But if someone is going through hormone changes, is very stressed, underslept and does a lot of close up work, well I would think that makes them likely to develop some myopia regardless of their genetic predisposition. And I would think that the same person, in other circumstances health-wise, could probably get away with murder as far as vision is concerned.
If I remember correctly, you did mention that you started like the rest of us with low myopia and it was made worse by lens use. Are you sure the genetic factor is strong for you?

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4 out of 5 siblings developed myopia. Neither of my parents were myopic, but they also only had primary education and were not readers, so did not have the environment likely to switch on the myopia genes. In my case it was not lens-induced, as I already had a fair degree of myopia before it was noticed and I got to see an optometrist for the first time. It depends on what one means by low myopia - but it is unlikely to have been as low as -1 or -0.75. He told me that he was surprised that I did not bump into every lamp-post that I passed. :smile: It was certainly aggravated by wearing glasses, although I did so as little as possible.

Of course I cannot be sure of this, but I am also not inclined to sweep a large amount of research on the genetic/epigenetic factors in myopia under the rug, just because it does not suit the EM narrative. These people are not all lens sellers. :crazy_face: As with all other aspects of our physiology, it is an interaction between nature and nurture.


I’m always very hesistant to mark anything as ‘genetic’ unless proven by a genetic test. Its easy to dismiss anything as ‘genetic’ because its so acceptable to do so these days, from doctors to the general public. I’ve learned this the hard way with my own and my family’s health.

Ditto. Well said. Its such a big piece of myopia but quite daunting to start reading about properly.

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