Vitamin A is of essential for normal growth of human body and skeleton as well as for night vision improvement. This vitamin contributes to normal growth of bone and tooth formation. Vitamin A is used as an antioxidant, but can be toxic at high levels. Of course, the amounts needed for the human body vary at different ages; for example, it is recommended to absorb up to 400 to 500 micrograms for infants, up to 600 to 900 micrograms for children, up to 700 to 900 micrograms for adults, up to 750 to 770 micrograms for pregnant women and up to 1200 to 1300 micrograms during lactation period.
Deficiency of vitamin A can affect human’s vision; for instance, xerophthalmia, an abnormal dryness of the cornea of the eye, with inflammation and ridge formation, typically is associated with vitamin A deficiency. At severe deficiency, the person will become blind but slight deficiency causes Nyctalopia. Vitamin A can be useful in treatment of skin wounds, pimples and other skin diseases. Its deficiency delays the healing of wounds. It also plays a key role in the treatment of warts or pimples, infections of various parts of the body, as well as respiratory diseases and mucosal cells.
Margarine, liver, kidney, milk, egg yolks, leafy yellow and dark green vegetables, apricots, cantaloupe and peaches are all sort of foods that contain vitamin A, which provides the body with the vitamins it needs. Vitamin A is stable against light and heat during common cooking procedures but decomposed by oxidation, dryness, very high temperatures and ultraviolet light. Therefore, it is recommended to use foods containing vitamin A in daily diet.