I was looking at a photo of a friend' who lives in Shanghai kid's birthday party on FB and all the attendee's under 40 were wearing glasses. So it made me curious,(was it diet or genetic ?) and I Googled away. "86% of HS students in Shanghai suffer myopia" () They find it's because the kids are never outside and they spend all their time staring at screens or paper. The copious amount of homework in China (often 5 hrs/night) doesn't help either.The rural poor in China don't share the problem. From the Economist " In 1970 fewer than a third of 16- to 18-year-olds were deemed to be short-sighted (meaning that distant objects are blurred). Now nearly four-fifths are, and even more in some urban areas. A fifth of these have “high” myopia, that is, anything beyond 16 centimetres (just over six inches) is unclear. The fastest increase is among primary school children, over 40% of whom are short-sighted, double the rate in 2000. That compares with less than 10% of this age group in America or Germany.
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 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." LINK;

Interesting, I'd often noticed that as well, but never looked into it. I wonder of it'll cause bigger problems in the long-term.

I'm sure part of the reason could be genetics, just too many with glasses. Perhaps the ones in the country simply can't afford/don't bother with corrective eyeglasses.

Or maybe the optician just directs them to the animal-feed shop when they make enquiries, LOL.

I always assumed genetics were the culprit, because most of my Asian friends back in the west also wore glasses from a relatively early age, and it's not like they were always glued to their textbooks. My whole family wears glasses (brother and sister started wearing them in their early teens), yet I don't... I do think being outdoors and "looking far/at the horizon" helps. Don't doctors recommend it as a way of exercising ones eyes? Still, genetics must play a large role. We're they simply not being diagnosed as much in the early 2000s, or has there really been such a big rise in eyesight problems? Still an interesting read.

yeah agreed, it is quite often in the western world if both parents wear glasses, their children will usually wear glasses

It isn't genetic. Only 1/3 of the kids parents were myopic & 80% of the kids are.

wackyjacky wrote:It isn't genetic. Only 1/3 of the kids parents were myopic & 80% of the kids are.

But you concede that 30% could be genetic and the rest acquired?

They may have a genetic disposition which is compounded by artificial light, sounds more like it to me.