Last month, my five-year-old daughter, Gillian, and I visited our local ophthalmologist for routine eye exams. Gillian's last visit was when she was 18 months old and, now that she's in full-day kindergarten, I wanted to catch any vision problems that could inhibit her learning. I discovered she's slightly near-sighted, but doesn't require vision correction yet. Most kids, the doctor assured me, outgrow near-sightedness (also called myopia) by puberty.
According to the Canadian National Institute for the Blind (CNIB), myopia is an inherited condition, and few factors outside of genetics cause the condition. However, developing research out of Australia suggests a link between the alarming rise in myopia and the significant amount of time children spend indoors.
Kathryn Rose, head of orthoptics at Sydney's University of Technology, spoke on CBC's The Current earlier this week about the high rate of myopia in children living in East Asia. For example, rates of myopia in young men in South Korea are as high as 96.5 percent. A study published in the journal Nature revealed that 90 percent of teenagers and young adults in China are myopic, compared to only 10 to 20 percent 50 years ago. (The rate among Canadian adults is 35 to 45 percent, and six percent in children.) According to Rose, this sharp increase cannot be attributed to genetics since our genes do not change that fast. While one hypothesis was that the emphasis on studying and reading in East Asia could be the source of higher rates of myopia, researchers now believe lack of daylight may be the issue.
After the analysis of the habits and vision of thousands of kids, researchers believe they've found the culprit: lack of time spent outdoors. Sunlight stimulates the release of dopamine (a growth inhibitor) in the retina, which blocks the elongation of the eye—the cause of myopia. The study published in Nature also found that by adding only 40 minutes outdoor studies a day decreased the rate of myopia in students by 10 percent.
Winnipeg-based ophthalmologist Gillian Robinson says that "as with any other area of health and vision care, our knowledge is always evolving." While she hasn't yet written a prescription for kids to spend more time outside, Robinson likes the idea of getting kids outdoors if it means improving their eye health. "For all the opportunities we have in Canada to enjoy the outdoors and how easy it is to get outside, I don't think there is any reason why we shouldn't all make a point of it," she says.
So, in case you needed another reason to soak up that springtime sunshine, grab everyone's sunglasses and take your kids outdoors—their eyes will thank you for it.