I heard carrots improve your vision.. its a load of bollocks
Fish oily fish
A lack of the right vitamins will cause problems in your eyes, but having a healthy balanced diet doesn't do anything especially helpful towards keeping your eyes healthy. Your eyes will always deteriorate with age and there's nothing you can do about it.
Some diseases such as diabetes can also cause problems with your vision.
I've always healthy and I never had a problem with my ajs.