I remember as a kid, my mom would always get a bit upset when I sat too close to the TV screen. “Don’t sit so close, you’ll lose your eyesight!”, she’d say. I’d wonder what peer-reviewed study she’d gotten that information from, and question her research methods. Okay, maybe I wouldn’t; I was like 7 years old at the time, and I didn’t know very much about rigorous scientific analysis. That said, I did end up with myopia – nearsightedness. Was it because I spent too much time too close to the TV screen?
The answer to that question is: maybe? There’s no evidence of a strong causal link between how close you sit to a screen and myopia, but there seems to be a correlation between the two. There has been a startling increase in myopia over the last several years. In fact, sixty years ago, about 10-20% of the Chinese population was myopic; today, about 90% of teens and young adults are. For years, we suspected that myopia was mostly genetic, but such a sharp increase couldn’t be attributed to genes alone; they simply won’t change populations that drastically, that quickly.
That points pretty strongly to environmental considerations. What’s changed in the past 60 or so years? Well, the prevalence of smartphones and tablets are certainly one thing – is digital eye strain to blame? Researchers aren’t quite ready to give blue light all the credit just yet; rather, they speculate that the eye is adapting to the environment it’s raised in. In other words, when the eye is always focused on something nearby, it develops to focus on close-up objects instead of objects that are far away. That means that if you were to spend all of your waking hours staring at books, you might end up with the same effects as people who spend all their time staring at smartphones.
As a parent, or a curious youngster who loves reading optometry blogs, what are you to do? Well, there’s a glut of evidence that points to a great way to reduce your chances of developing myopia; get outside. In much the same way that we’re not entirely sure why spending time indoors and looking at screens seems to correlate to myopia, we’re not entirely sure why spending time outside seems to help matters; we are, however, pretty confident there’s a reasonable link. That means that conventional wisdom about spending time outdoors seems to be right, even if we’re not quite sure why. We could speculate, but that speculation won’t get us far, and might lead to more confusion than anything.
For those who do have myopia, stop by and visit your friendly Winnipeg optometrist so we can chat. We can get you glasses to help you see, no doubt, but we can also talk about steps you can take to reduce your chances of the myopia developing further. Eyes do most of their development before we’re adults, but it’s still a good idea to get checkups on the regular. We’ll see you soon!