Vitamin A is the Vitamin Deficiency that leads to cataracts and sometimes complete blindness if you don't get your required amount of Vitamin A.
The more Vitamin A you intake the less chance you have of developing cataracts and/or becoming blind.
Vitamin C and beta carotene can also help to prevent cataracts.
A good source of beta-carotene are sweet potatoes, kale, carrots, turnip and mustard greens, spinach, and butternut squash.
Eating those foods can prevent cataracts from developing and may even prevent total blindness.