A new report has found that 80-90 percent of Asian children (in Singapore, China, Taiwan, Hong Kong, Japan, and Korea) suffer from myopia, or nearsightedness. And it’s not only Asian; myopia is also on the rise in Europe.
While science has uncovered genes linked to condition, the sudden increase in numbers points to environmental factors, and the main cause at the top of most experts theory list is due to an increased amount of time spent at computer screens, televisions and books, instead of playing outside.
Myopia causes the eyeball to become elongated; this results in the retina being unable to focus on incoming light because of the distorted shape.Image Credit: Jack Everett, 2011.
Numerous studies in humans and animals have shown a link between reading at close distances and developing elongated eyeballs. Other studies have shown that a lack of bright light may also lead to myopia.
In the past 30 years, myopia in Singapore has increased three fold amongst all three major ethnic groups – Chinese, Indian and Malay. When researching environmental causes for the increase in numbers studies showed that schoolchildren who read more than two books per week were more likely to have myopia.
Similar research in both Singapore and Australia found correlations between the amount of time spent outside and lower rates of myopia. Research on animals showed that while intense UV rays damage the eyes, a small amount helps to stimulate dopamine release, which has been linked to eye growth. A recent study in tree shrews also suggest that bright fluorescent lights could help fight off myopia.
Other research suggests that the way we read may also be a factor in developing myopia. For example ultra-orthodox Jewish boys who study the Torah intensely at close distance while swaying have higher rates of myopia than girls, who don’t.
While the studies are far from conclusive, it does give us one more reason to step away from the computer screen, and go catch some rays whilst relaxing in the sun.