Why is there an epidemic of short-sightedness in Asia?

Asked by: Joanne Moore, York

In China, around 90 per cent of young people are now affected with short-sightedness – a six-fold increase since the 1950s. In Seoul, 96.5 per cent of 19-year-old men are affected.

The problem is also spreading worldwide. The cause is hotly debated, but attention is focusing on the lifestyle of 21st-Century children – specifically, getting too little exposure to daylight, which seems to influence eye development.

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