导读：据法新社5月4日报道，澳大利亚国立大学研究者在医学杂志《柳叶刀》上发表文章称，东亚青少年十之有九近视，与基因或阅读这样的静态活动无关，最主要的原因是缺乏户外活动，太少晒太阳。
东亚青少年90%的近视因晒太阳太少
据法新社5月4日报道，澳大利亚国立大学研究者在医学杂志《柳叶刀》上发表文章称，东亚青少年十之有九近视，与基因或阅读这样的静态活动无关，最主要的原因是缺乏户外活动，太少晒太阳。
文章称，晒太阳能够刺激化学物质多巴宁(dopamine)在体内生成，这类化学物质有助阻止眼球伸长，防止扭曲眼球焦点。
该文作者，澳大利亚国立大学的伊恩•莫干(Ian Morgan)研究员表示，东亚的近视学生数量最多，如在中国、日本、新家坡和韩国，近视率几乎达到80%-90%。例如，新加坡学生平均每天在户外的时间是30分钟，近视率达到90%。而每天户外活动达3小时的澳大利亚学生近视率只有10%左右，非洲青少年的近视率则只有2-3%。
莫干称，学习也许并不是近视的原因，东亚学生的近视问题很大程度上是由于环境而不是基因。最易患近视的人群其实是闭门不出的人，不管他是在室内阅读、玩游戏还是看电视。
Myopia
Prof Ian G Morgan PhD , Prof Kyoko Ohno-Matsui MD , Prof Seang-Mei Saw PhD
Myopia has emerged as a major health issue in east Asia, because of its increasingly high prevalence in the past few decades (now 80鈥?0% in school-leavers), and because of the sight-threatening pathologies associated with high myopia, which now affects 10鈥?0% of those completing secondary schooling in this part of the world. Similar, but less marked, changes are occurring in other parts of the world. The higher prevalence of myopia in east Asian cities seems to be associated with increasing educational pressures, combined with life-style changes, which have reduced the time children spend outside. There are no reported major genes for school myopia, although there are several genes associated with high myopia. Any genetic contribution to ethnic differences may be small. However, to what extent many genes of small effect and gene-environment interactions contribute to variations in school myopia within populations remains to be established. There are promising optical and pharmacological interventions for preventing the development of myopia or slowing its progression, which require further validation, and promising vision-sparing treatments for pathological myopia.
文献链接：https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(12)60272-4/abstract
