Japan is in the top 3 nations for highest myopia rates in young adults, with some studies showing as high as 80% having nearsightedness.

For comparison, US is at 30-40%.

A common characteristic in myopic adults is elongated eyeballs (when eyeballs are misshaped).

Lack of time spent outdoors is considered to be a factor that increases myopia rates, yet I see more kids outside in Japan doing extracurricular activities than in US.

One thing I’ve noticed is that just about everywhere you go there is a lack of natural lighting so people use lights.

There’s no strong causal link between indoor lightning and myopia but I suspect it’s plays a much larger role than anyone imagines or cares to admit. I’d be curious to see if Singapore or South Korea also has a culture of keeping the lights on during the day 🤔