Night Light Not Implicated in Nearsightedness, Reports Say

Contrary to a widely circulated report released last May, two new studies indicate that sleeping with a night light does not make infants more likely to become myopic, or nearsighted. Animal studies had suggested that persistent exposure to light during infancy could impair development of the eye, producing myopia, and a study of 479 children by Dr. Richard A. Stone and his colleagues at the University of Pennsylvania supported that conclusion. But two efforts to reproduce the finding, reported in today’s Nature, failed.

One study of 1,120 children by a team headquartered at Ohio State University and a second of 213 children by researchers at the New England College of Optometry found that the incidence of myopia was roughly the same, no matter what lighting conditions the children slept in. But the teams found that myopic parents were much more likely to use night lights than those with normal vision, perhaps to help them navigate the nursery. Myopia is largely inherited, and that finding may have influenced the original results. But Stone responded that the two studies were performed after results of his study were announced, and that parents may have been reluctant to report a behavior--using night lights--that could have harmed their children.

--Compiled by Times medical writer Thomas H. Maugh II