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科學(xué)家們說亞洲離校生中患有視力問題的人數(shù)這幾年急劇上升。研究人員在科學(xué)雜志《the lancet》上發(fā)表報告指出幾乎90%的年輕人患有近視—他們認(rèn)為主要原因是學(xué)生們有繁重的功課及沒有足夠的室外活動而缺乏室外光線。請聽bbc英國廣播公司科學(xué)記者matt mcgrath發(fā)回的報道:

the scientists say that young people need up to three hours a day of outdoor light, but many infants are also missing out as they nap during lunch time. dr. ian morgan is the lead author of the study:

i think what's happened in south-east asia is we've got a double whammy. we've got the massive educational pressures and we've got the construction of a child's day in a way that really minimises the amount of time they spend outside in bright light.

the scientists say that genetic factors, long thought to play a big role in short-sightedness, are not as important as the environment. they point to singapore as a place with several distinct ethnic groups, all of whom are now suffering high levels of myopia.

the authors suggest that mandatory time outdoors should be considered by educational authorities across south-east asia as a way of dealing with the problem.