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> Asian are prone to nearsightedness. Of people aged 20 and under, 96% of South Koreans, 95% of Japanese, 87% of Hong Kongers, 85% of Taiwanese and 82% of Singa

> Asian are prone to nearsightedness. Of people aged 20 and under, 96% of South Koreans, 95% of Japanese, 87% of Hong Kongers, 85% of Taiwanese and 82% of Singaporeans are affected by the condition, according to Kubota. Wow, this is so stark. Is it genetic or is it something lifestyle related? It would seem strange if it was genetic as glasses were invented quite late and vast population suffering from near sightedness without glasses seems like such a disadvantage.

givemeethekeys 5y ago
Perhaps living in cities with tall buildings produces a higher rate of nearsightedness since the eyes don't get to look to the horizon much.
jaggederest 5y ago
It seems that, like the way that environmental factors affect jaw development[1], environmental factors that are different between modern lifestyles and pre-historical ones drive the development of myopia.[2] But there have always been a percentage of people who are myopic due to other factors, as well, so it's not a single story. [1] https://www.bbc.com/news/science-environment-15823276 https://www.bbc.com/news/science-environment-15823276 [2] https://www.aao.org/editors-choice/sunlight-exposure-reduces-myopia-in-children https://www.aao.org/editors-choice/sunlight-exposure-reduces...
powerapple 5y ago
the most effect you can have on your eyes can be cause by study. When you have to use your eyes and your brain at the same time. My parents told me that too much video games is bad for my eyes, from my experience, I became shortsighted in the period I had to study a lot and not playing video games.
- beebeepka 5y ago
  Ah, but is the worst kind if non-binary thinking! Studying is good, and therefore it cannot be bad for your eyesight. Games, on the other hand, are bad and can only be associated with negatives. "You'll get this when get older"
pbazarnik 5y ago
Exposing eyes to sunlight (or high intensity light) is a very important factor preventing and reversing myopia [1] There was also Australian paper I cant find now, showing that prevalence of myopia in Asians in Australia is much lower due to school systen encouraging more free time and play outdoors. (not explainable by genetic factors) Children must play outside in the sun or they become myopic. [1] https://pubmed.ncbi.nlm.nih.gov/29371008/ https://pubmed.ncbi.nlm.nih.gov/29371008/
- qsdf38100 5y ago
  I heard that playing outside also generally makes you focus on much more distant objects, and that as the eye optimizes for a "at rest" focal point that best fits what you're looking at most of the time. So when you're looking at close screens or books for most of your day, the eye makes that be the "at rest" state, but now distant objects are blurry. Now if you insist on having distant objects not blurry (by wearing glasses _all the time_), it's the same situation again and the eye will "adapt" even more, and you'ell get more power glasses, and so on... If that's true, then people with myopia shouldn't wear their glasses _all the time_, particularly when staring at close objects (screens and books). I have myopia and that explanation fits my experience. Most of the time I'm looking at a screen not wearing my glasses, and the screen is exactly at the right distance for me to not to have focus, so my eye is "at rest" for most of the day. It sounds weird that a lot of eyes are dysfunctional. Maybe we don't understand how eyes find a trade-off that best suits your average focal distance. It also gives a rational as to why myopia went from a few 1% to 50% of the population in some countries. People started staring at close objects. I don't know if it's actually true, but it makes a lot of sense to me.
  - akiselev 5y ago
    > So when you're looking at close screens or books for most of your day, the eye makes that be the "at rest" state, but now distant objects are blurry. Now if you insist on having distant objects not blurry (by wearing glasses _all the time_), it's the same situation again and the eye will "adapt" even more, and you'ell get more power glasses, and so on... My optometrist specifically prescribes me lenses/contacts that are slightly worse than optimal (i.e. -2.25 instead of -2.5) based on the fact that I stare at a computer screen the entire day. IIRC her explanation was along these lines, and I've had no degradation in eyesight in nearly a decade since. (I am not an optometrist, for god's sake find your own)
mellavora 5y ago
Lifestyle. It comes from spending too much time indoors instead of outside. https://pubmed.ncbi.nlm.nih.gov/33878199/ https://pubmed.ncbi.nlm.nih.gov/33878199/
ammmir 5y ago
studying too much at close distance, and not spending enough time outside
p0larboy 5y ago
Notice how these mentioned Asian countries are countered that focus on academics. I'm a Singaporean and we spent alot of time in our younger years straining our eyes on books and computers.

givemeethekeys 5y ago

Perhaps living in cities with tall buildings produces a higher rate of nearsightedness since the eyes don't get to look to the horizon much.

jaggederest 5y ago

It seems that, like the way that environmental factors affect jaw development[1], environmental factors that are different between modern lifestyles and pre-historical ones drive the development of myopia.[2] But there have always been a percentage of people who are myopic due to other factors, as well, so it's not a single story. [1] https://www.bbc.com/news/science-environment-15823276 https://www.bbc.com/news/science-environment-15823276 [2] https://www.aao.org/editors-choice/sunlight-exposure-reduces-myopia-in-children https://www.aao.org/editors-choice/sunlight-exposure-reduces...

powerapple 5y ago

the most effect you can have on your eyes can be cause by study. When you have to use your eyes and your brain at the same time. My parents told me that too much video games is bad for my eyes, from my experience, I became shortsighted in the period I had to study a lot and not playing video games.

beebeepka 5y ago
Ah, but is the worst kind if non-binary thinking! Studying is good, and therefore it cannot be bad for your eyesight. Games, on the other hand, are bad and can only be associated with negatives. "You'll get this when get older"

pbazarnik 5y ago

Exposing eyes to sunlight (or high intensity light) is a very important factor preventing and reversing myopia [1] There was also Australian paper I cant find now, showing that prevalence of myopia in Asians in Australia is much lower due to school systen encouraging more free time and play outdoors. (not explainable by genetic factors) Children must play outside in the sun or they become myopic. [1] https://pubmed.ncbi.nlm.nih.gov/29371008/ https://pubmed.ncbi.nlm.nih.gov/29371008/

qsdf38100 5y ago
I heard that playing outside also generally makes you focus on much more distant objects, and that as the eye optimizes for a "at rest" focal point that best fits what you're looking at most of the time. So when you're looking at close screens or books for most of your day, the eye makes that be the "at rest" state, but now distant objects are blurry. Now if you insist on having distant objects not blurry (by wearing glasses _all the time_), it's the same situation again and the eye will "adapt" even more, and you'ell get more power glasses, and so on... If that's true, then people with myopia shouldn't wear their glasses _all the time_, particularly when staring at close objects (screens and books). I have myopia and that explanation fits my experience. Most of the time I'm looking at a screen not wearing my glasses, and the screen is exactly at the right distance for me to not to have focus, so my eye is "at rest" for most of the day. It sounds weird that a lot of eyes are dysfunctional. Maybe we don't understand how eyes find a trade-off that best suits your average focal distance. It also gives a rational as to why myopia went from a few 1% to 50% of the population in some countries. People started staring at close objects. I don't know if it's actually true, but it makes a lot of sense to me.
- akiselev 5y ago
  > So when you're looking at close screens or books for most of your day, the eye makes that be the "at rest" state, but now distant objects are blurry. Now if you insist on having distant objects not blurry (by wearing glasses _all the time_), it's the same situation again and the eye will "adapt" even more, and you'ell get more power glasses, and so on... My optometrist specifically prescribes me lenses/contacts that are slightly worse than optimal (i.e. -2.25 instead of -2.5) based on the fact that I stare at a computer screen the entire day. IIRC her explanation was along these lines, and I've had no degradation in eyesight in nearly a decade since. (I am not an optometrist, for god's sake find your own)

mellavora 5y ago

Lifestyle. It comes from spending too much time indoors instead of outside. https://pubmed.ncbi.nlm.nih.gov/33878199/ https://pubmed.ncbi.nlm.nih.gov/33878199/

ammmir 5y ago

studying too much at close distance, and not spending enough time outside

p0larboy 5y ago

Notice how these mentioned Asian countries are countered that focus on academics. I'm a Singaporean and we spent alot of time in our younger years straining our eyes on books and computers.