Vitamin A is a vitamin that is needed by the retina of the eye in the form of a specific metabolite, the light-absorbing molecule retinal, that is necessary for both low-light and color vision. Vitamin A also functions in a very different role, as an irreversibly oxidized form of retinol known as retinoic acid, which is an important hormone-like growth factor for epithelial and other cells.

The daily dose for vitamin A is 2000-3500 IU/day. taking Vitamin A more than the recommend daily use can injury your lever.

Food that contain Vitamin A: lever, fish, carrot, broccoli, egg, mango, milk.