Sunlight Improves Your Eyesight

The Economist has an article out about Asian children, particularly those from wealthier families who place a high value on education, reading, and technology, and how they tend to have poorer eyesight because they don't spend enough hours outside when the sun is shining.  I don't know what it is like in South Korea or Singapore or Taiwan, but if they are anything like Shanghai, then I doubt that they'll get enough sunlight to keep stem this trend.  

"The incidence of myopia is high across East Asia, afflicting 80-90% of urban 18-year-olds in Singapore, South Korea and Taiwan. The problem is social rather than genetic. A 2012 study of 15,000 children in the Beijing area found that poor sight was significantly associated with more time spent studying, reading or using electronic devices—along with less time spent outdoors. These habits were more frequently found in higher-income families, says Guo Yin of Beijing Tongren Hospital, that is, those more likely to make their children study intensively. Across East Asia worsening eyesight has taken place alongside a rise in incomes and educational standards."

The author explains the causes:

"The biggest factor in short-sightedness is a lack of time spent outdoors. Exposure to daylight helps the retina to release a chemical that slows down an increase in the eye’s axial length, which is what most often causes myopia. A combination of not being outdoors and doing lots of work focusing up close (like writing characters or reading) worsens the problem. But if a child has enough time in the open, they can study all they like and their eyesight should not suffer, says Ian Morgan of Australian National University."

With all of the hours spent indoors, it reminds me of the unfortunate victims from one of Ray Bradbury's short stories, titled "All Summer in a Day," about a class of school aliens on Venus, a world of constant rainstorms, where the sun is only visible for one hour every seven years.  You can read that short story here.