Daily Court Reporter - News Ohio State study: Outdoor play, light good for kids' eyes
Ohio State study: Outdoor play, light good for kids' eyes
KEITH ARNOLD, Daily Reporter Staff Writer
A recent Ohio State University study has found that more time outdoors has a protective effect and reduces the chances that a child would go on to need myopic refractive correction in the future.
And the magnitude of the effect was impressive, researchers noted.
A child of two nearsighted parents has about a 60 percent chance of needing glasses, per hereditary genetic effects and if time spent outdoors is low.
More time outdoors - about 14 hours per week - can nearly neutralize that genetic risk, College of Optometry Dean Karla Zadnik and professor Don Mutti found in the comprehensive study.
The chance that a child with more outdoor time would need glasses was slashed to about 20 percent - the same chance as a child with no nearsighted parents claims.
Zadnik and Mutti studied the question in excess of 20 years in 4,979 children as part of the Collaborative Longitudinal Evaluation of Ethnicity and Refractive Error Study which was to consider effects of near-work, computer use and watching television in their proper place.
Myopia typically starts during the early elementary school years, a press release detailed. The condition results in the eye growing too long for distant rays of light to focus accurately on the back of the eye, resulting in a blurry image.
The researchers posed the question: What's so good about being outdoors for a child?
One, is that children may exercise more when they are out of doors and that exercise is somehow protective, they reckoned.
Another theory is that more ultraviolet B radiation from the sun makes for more circulating vitamin D, which somehow prevents abnormal childhood eye growth and myopia onset.
A third consideration is that light itself slows abnormal myopic eye growth and that outdoor light is simply brighter.
The dominant theory, however, is that the brighter light outside stimulates a release of dopamine from specialized cells in the retina, the researchers reasoned. Dopamine then initiates a molecular signaling cascade that ends with normal growth of the eye and no myopia.
The study's results were published originally online at The Conversation.
Date Published: October 31, 2017