There is a nearsighted epidemic going on in the world. In the 1970’s about 20% of NorthAmerican and Asian 20 year olds were nearsighted. Now it is about 40% of North American and 96% of Asian 20 year olds.
While we don’t fully understand why or how, studies seem to indicate that more time spent outdoors seems to protect against becoming nearsighted. Studies show that about 90-120 minutes outdoors in the sun can reduce nearsightedness. What we do know is that it is not related to amounts of upclose work, as the studies have corrected for that. In fact, there are some schools in Taiwan that have ‘bright-light’ classrooms where the walls and ceilings are made of see through plastic and these students seem to be less nearsighted than in other schools.