眼睛大的人更容易近视？_BEC初级作文

眼睛大的人更容易近视？

Experts believe this might be because the eyeball grows too large, which causes the light to focus in front of the retina, rather than on it.

Short-sightedness is on the rise in Britain, with up to 50 per cent of people now estimated to have it.

One possible explanation for this is that our eyeballs are getting larger because we are spending more time indoors. A lack of outdoor light in our early years causes the size of the eyeball to increase. But the larger the eyeball, the more likely a person is to be short-sighted, explains Andy Luff, a consultant ophthalmic surgeon at Optegra, a chain of private eye hospitals.

'While big eyes can certainly look beautiful, the fact is that if your eyes are slightly too big, this will cause you to suffer short sight. If the eyeball is too big, the light focused by the lens of the eye does not reach the back the retina, where images are processed.

'If the eye is only 1 mm longer than 24 mm (the average size from front to back) a person will be significantly short-sighted. Longer than the average by 2 to 5mm will make you highly short-sighted.'

Dr Luff explains that in the past we thought the eye grew too large and became short-sighted due to genetic factors.

'Although genetics is still the most important reason behind short-sightedness, lack of exposure to outdoor light is another possible cause. And it's the one preventable cause which can be addressed in childhood.'