Question: What is it that makes someone short or long sighted?

Emma Reid answered on 17 Jun 2014:

Hi Lucy!
When someone is short sighted, light coming into the eye forms an image before it reaches the retina and this makes objects in the distance look all blurry. We don’t know exactly what causes this condition but it’s likely that genetic and environmental factors are involved. Long sightedness is the opposite to short sightedness because in this case light forms an image behind the retina and makes close up objects look blurry. You can inherit long sightedness from your parents and diabetes can sometimes cause it too but this is rare. Hope this answers your question Lucy! 🙂
Emma