Researchers suspect that bright outdoor light helps children’s developing eyes maintain the correct distance between the lens and the retina — which keeps vision in focus. Dim indoor lighting doesn’t seem to provide the same kind of feedback. As a result, when children spend too many hours inside, their eyes fail to grow correctly and the distance between the lens and retina becomes too long, causing far-away objects to look blurry.
This leads us to a recommendation that may satisfy tiger and soccer moms alike: if your child is going to stick his nose in a book this summer, get him to do it outdoors.
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