Outdoor play tied to better eyesight, but why?


(CBS) Parents worried about their kids' eyesight will want to take a look at a new study from England. It suggests a simple way to reduce the risk for nearsightedness - and it doesn't come in a pill bottle or an eye dropper.

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It's spending more time out of the house.

"Increasing children's outdoor time could be a simple and cost-effective measure with important benefits for their vision," Dr. Anthony Khawaja, an ophthalmology professor at the University of Cambridge, said in written statement.

For the study - presented at an American Academy of Ophthalmology conference Monday in Orlando, Fla. - researchers analyzed eight previous studies involving more than 10,000 children and adolescents. The study showed that nearsighted kids spent an average of four fewer hours per week outdoors, compared with kids who were farsighted or had normal vision.

What's so special about being outdoors?

Nearsightedness "could be caused by not enough UV radiation, but it could also be spending less time looking into the distance or not enough physical activity, "study co-author Dr. Justin Sherwin, told The Telegraph.

Khawaja said more research is needed to give an exact recommendation of how much outdoor time might be helpful. He said previous research suggested that boosting outdoor time could keep existing nearsightedness from getting worse as well as preventing nearsightedness in the first place.

Nearsightedness, a.k.a. myopia, is very common around the world, with some studies showing the condition affecting 42 percent of people in the U.S., and more than 80 percent of peope in some Asian Countries.

The National Institutes of Health has more on nearsightedness.