Quote Originally Posted by Big King Sanctaphrax
I think the carrots thing comes from the fact that they contain beta-carotene, which is converted into vitamin A, which is necessary for vision. Any beyond the required amount won't improve it, though.
I heard polar bear liver has a lethal concentration of Vitamin A. That's why the Inuit don't eat it.

Guess if it kills you it doesn't do much for your vision either.