I don’t want to say “glasses cause nearsightedness” because it’s not precise enough. Better to say glasses exacerbate nearsightedness so where you might’ve stayed at -1.25 to -1.5, you end up virtually blind by going to -4.0 or beyond by wearing glasses daily, which increases your prescription until it creeps up year by year.
I was nearsighted in fifth grade, and in seventh grade I got glasses at -1.0 prescription. I noticed that wearing it all day would cause chafed skin where the nose pads touch and my vision felt tired/blurry. So I stopped wearing the glasses and just sat at the front.
Astigmatism correction also seems to worsen astigmatism, just like spherical correction.
Since then, my vision has not become that much worse. Not accounting for genetic and extreme cases, the cause of nearsightedness is mainly the lack of sunlight and using glasses for near work plus the yearly ratcheting up in prescription strength.
Once, when I had a strong fever and headache, my eyes felt like they were being compressed from the back forward. During that time, my vision was much better.
There are many anecdotal reports on reversing myopia or even inducing it. It’s clear that if everyone had perfect vision and health, optometrists who rely on yearly checkups would go out of business.
It’s kind of sad, really. I meet a lot of people who are nonfunctional daily without glasses and are considering dangerous laser eye surgery. If only they had spent more time outside and not used glasses so much, they would be in a much better place. Yet when I tell them this, they don’t realize it or believe it.
As Ibn Khaldun says, God makes day and night. (Some people are blessed with the power of understanding, some are doomed to suffer.)
Other misc tips wrt vision:
- Don’t look at the sun during a solar eclipse, even if you have protective glasses. Seeing the change in the environment and how the animals would start chirping was much more interesting than looking at a circle overlap another circle.
- Don’t be too curious at where bright lights are coming from at night. Once I saw some cool purple lights at the side of a wall. I peeked in to look at it and it really hurt.