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Comment by modeless | Hacker News Reader

You are thinking of myopia. The article is about presbyopia. They are quite different.

The eye has a range in which it can focus. Myopia is a shift of the range due to the shape of the eye, while presbyopia is a shrinking of the range due to hardening of the lens.

                 zero        infinity
    --------------|-------------|--------------
    ----------------|            |------------- < normal focus range
    ----|            |------------------------- < range of myope 
    ----------------------| |------------------ < range of presbyope

Only some people get myopia. Everyone gets presbyopia.

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Yep. Myopia move the focus of the eye from infinity to 1m/diopters. I'm myope with 4 diopters, and my focus is at 25cm. This means that even being also presbyope, I can read a book without lens if I put it at 25 cm from my eye.

Both are collagen disorders, both seem to correlate to UV light exposure (lack of same.) Do drop a study citation if you know of a study showing otherwise, I'd be most interested.

On the contrary, I'm not aware of any evidence for UV providing protection against presbyopia (though I haven't done extensive research). This article seems to suggest the opposite. https://www.ncbi.nlm.nih.gov/m/pubmed/2677104/

You may have flipped the meaning, or it's more complex. The abstract is unclear. To quote: "Of all factors reported to affect the onset of presbyopia, UVR has the most scientific support..." Of course, if this is similar to other effects, such as longevity, intermittent UV exposure will be harmful, and constant exposure helpful.

This comment is great: it corrects a common misconception with detailed technical information, ASCII art, and the word "myope"!

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