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I don't know why western media always talks about myopia (in Asia) as if it's some sort of mystery. Where I'm from, everyone believes that myopia is caused by..
by nsonha 3y ago
I don't know why western media always talks about myopia (in Asia) as if it's some sort of mystery. Where I'm from, everyone believes that myopia is caused by... the habit of looking at close objects for prolonged periods, such as electronic devices or books. Like how shocking (it should not if you know how muscles around your eyeballs work). I think it's even written so in the textbooks.
- bryanlarsen 3y agoYes, that's a common belief in the West as well, and used to be generally accepted. But there's a very strong correlation between looking at close objects for prolonged periods and being inside so it's easy to understand why it was misunderstood for so long.
- nsonha 3y agoyou seem to think the real cause is "being inside" and not using your eyes in a particular way? (looking at close objects...). What is the exact mechanism by which being inside affects your eyes then?
- croes 3y agoArtificial lighting? Less sunlight? Lower light intensity?
- nsonha 3y agoyes, there is a theory on how the muscles of the eyes become "miscalibrated", so to speak, if you only look at close things. What is the exact mechanism of the "lower light" theory then?
- deleted 3y ago[deleted]
- jgtrosh 3y ago> There is preliminary evidence that the protective effect of outdoor activities on the development of myopia is due, at least in part, to the effect of long hours of exposure to daylight on the production and the release of retinal dopamine.
- nsonha 3y agothank you, I skimmed over this in the article
- smallnix 3y agoPlease read the article. Its about that. I'll try to explain what I understood from the article: the natural sunlight makes your body release dopamine, dopamine causes the eye not to elongate, not elongation equals not having near-sightedness. Probably I got that only half right. Anyhow the article claims it's not looking at close things and the real cause is being inside.
- cromulent 3y agoThat's the subject of the article.
- arrowleaf 3y agoClose-up work (crafts, reading, computers) causing myopia 'makes sense', I heard the same thing as a kid in the States. It makes me wish we would have had more P.E. classes outside, rather than 'giving our eyes a break' by playing kickball indoors under fluorescence.
- nsonha 3y agothe problem with playing indoor is that your "eye break" only goes so far as the walls of the space, still "close objects" in relative terms. In nature, humans use their eyes to gaze landscape, stars... really far things.
- garblegarble 3y agoMy understanding is that 20 feet or so is optical infinity, so whether you're looking at an object 20 feet away or 20 light years away, your eye muscles are just as relaxed (hence the 20-20-20 recommendation: every 20 minutes, stare at an object 20 feet away for 20 seconds)
- antisthenes 3y agoI don't know about you, but where I spent my childhood, most things indoors were much closer than 20 feet away. That's a fairly large room, and we typically don't focus on the furthest point while indoors anyway. So with the 20ft requirement, it's a lot easier to fulfill while being outdoors.
- garblegarble 3y agoOh yeah definitely - I was purely commenting on the parent comment's "really far" claim, and noting that it's all the same to the eye muscles once you hit 20 feet - you don't have to (no pun intended) set your sights on the stars to relax your eye muscles.
- arrowleaf 3y agoWell, the real problem is that children's eyes aren't getting enough sunlight exposure to trigger dopamine production, which regulates the lengthening of the eyeballs, while cooped up inside. Eye strain is muscle fatigue, unrelated to myopia.
- deleted 3y ago[deleted]
- gniv 3y agoThis used to be the leading theory, indeed. Turns out it was wrong, as the article explains.