Why We're Losing Sight
"This study confirms high myopia prevalence and a high rate of myopia progression among law students. The strongest association, especially in those with myopia onset before college, was a relation of myopia progression during law school with less daily exposure to darkness, a potential risk factor previously identified in childhood myopia," the researchers write.
Other researchers, however, argue that it's not too much light exposure, but too much time spent hunched over textbooks that has studious students squinting.
Karla Zadnik, OD, PhD, and colleagues at the Ohio State University College of Optometry in Columbus found in a study of eighth graders that children who had at least one myopic parent, who did more near work and/or less sports, and who scored higher in reading on a standardized test were more likely to be myopic. Significantly, increasing the amount of near work doubled the risk of becoming myopic, but that was less significant an effect than having a myopic parent. The finding suggests both heredity and environment play a role, the researchers say.
A third study found that among 71 nearsighted schoolchildren, myopia progressed more during the school year, when the kids were more likely to be doing the three "R's" or working at a computer, than it did during the summer months, when they were more likely to use their eyes for tasks requiring distance vision.
Researcher George W. Fulk, PhD, OD, a professor of optometry at Northeastern State University in Tallequah, Okla., tells WebMD that when they measured the eyes of these students, they found that the change in nearsightedness was much greater after three months of school than after three months of vacation, and that the changes could be explained by the need for the eyes to adapt to close work during the academic year.
The bottom line is that when your mom yelled, "Get your nose out of that comic book or you'll ruin your eyes!" -- she may just have been right.