It is estimated that half of the world’s population will become myopic by 2050.
— ‘Outdoor activity and myopia progression in children’, National Institutes of Health, 2021.
My sister got diagnosed as myopic — nearsighted — when she was still in elementary school. She came home from school one day and confessed that she couldn’t read the blackboard. She claimed she needed glasses.
My dad was skeptical. Of everything. But especially, of things that cost money, like optometrists and glasses.
And he had good cause to be skeptical, because my sister’s two best friends had just gotten glasses. The cool-looking kind that was popular in the 1970s, when glasses switched from a symbol of physical weakness into a fashion statement.
Many really cool people were wearing glasses in the ’70s, like John Lennon. Elvis Costello. Elton John. Johnny Depp. Meryl Streep. Julia Roberts. Clark Kent.
Okay, we shouldn’t count Clark Kent, even though he was pretty handsome in glasses.
But John Lennon!
My sister pulled out her favorite weapon — tears — and my dad relented, finally.
Low and behold, my sister was in fact myopic. She really could not read the blackboard — much to my dad’s embarrassment.
According to what I’ve learned online, my sister was myopic because her eyeballs had stopped being ’round’ and had elongated into more of a football shape. This is not something that happens to everyone, but at the rate things are going, the whole world is going to be myopic someday.
This is a different problem from hyperopia — farsightedness — when you can’t read stuff up close. That’s generally a result of your eyes getting lazy and no one around to tell them to straighten up.
But we’re talking here about myopia. For good reason. Like, the whole world needing glasses.
Back in the 1990s, doctors still thought myopia was genetic. If your parents were myopic, well, good luck, you were probably going to be myopic. But an Australian scientist named Ian Morgan, at the University of Sydney, was studying the actions of dopamine as a retinal transmitter. I’ve heard of dopamine, but I had no idea it was a retinal transmitter. You learn something new every day, don’t you?
Apparently, something really weird was going on in Asia. The incidence of myopia among Asian children had increased over the past few decades, from about 20% of the population to 80-90%. Which was great for optometrists and the companies that manufacture glasses, but not so good for parents and kids. The ’70s fashions had gone out of style in the ’80s. Also, severe myopia can eventually lead to blindness in adults.
Obviously, this was not a problem of genetics, because 80-90% of Asian parents had not suddenly become myopic. Only their kids had.
In 2008, the Sydney Myopia Study published research showing that children who spent more time outdoors were less likely to become myopic. This was confirmed by comparing children of Chinese ancestry growing up in Australia and Singapore. The two groups had vastly different prevalence of myopia — 3% in Australia compared to 27% in Singapore at the age of 6. The children in Singapore reported less than one quarter of the time outdoors reported by those in Australia.
Singapore subsequently adopted voluntary increased time outdoors as its national myopia prevention strategy, and, with a bit more evidence, in 2010, Taiwan schools adopted a compulsory program requiring “2 hours per day outside”. The positive effects are even stronger when preschoolers are forced to play outside.
Scientists are not sure why being outside is good for your eyes, when you’re a child (especially if you’re an Asian child?) It’s possible you simply exercise your eyes differently outside. It’s possible that having fun (which doesn’t happen inside a classroom) generates chemicals that are good for your eyes. It’s possible honest-to-goodness sunlight is good for your eyes.
Maybe ‘all of the above’.
Why did my sister develop myopia, and I didn’t? We both spent a good deal of time outside, but maybe I had more fun.
Underrated writer Louis Cannon grew up in the vast American West, although his ex-wife, given the slightest opportunity, will deny that he ever grew up at all.