Other name(s):

b-carotene, beta-carotene, retinol, vitamin A-1

General description

Vitamin A is also called retinol. It was the first substance isolated in the group called vitamins. It is 1 of the 4 fat-soluble vitamins. This means it can dissolve in fats and oils. It’s found in animal products. Fat-soluble vitamins are stored in the body. They can build up to toxic levels if you take too much of them.

Precursors of vitamin A exist in plants. They’re called carotenoids. These are fat soluble but nontoxic, even in large quantities. The best-known carotenoid is beta-carotene. Both retinoids and carotenoids are good antioxidants.

Vitamin A is part of the reproductive process. It helps with the growth of sperm. It also helps with the growth of a baby in the womb. But high doses of vitamin A and synthetic retinols may lead to problems with growth in the womb. It may also lead to birth defects. Vitamin A seems to help the growing tissues in a baby in the womb. It also helps the placenta form during pregnancy.

Vitamin A is an important factor in growth throughout life. Vitamin A helps grow and maintain epithelial tissues. These include mucous membranes, the lining of the gastrointestinal tract, lungs, bladder, urinary tract, vagina, cornea, and skin. Vitamin A also helps the growth of bones and teeth.

Vitamin A prevents drying of the skin. This may protect the body from infectious diseases. It also helps maintain the immune system.

Vitamin A is also needed for night vision. Retinol (a vitamin A metabolite) combines with opsin (a pigment in the retina of the eye) to form rhodopsin. This is a chemical that helps with night vision.

Medically valid uses

Vitamin A helps with the reproductive process, growth, and development. It also keeps eyes and skin healthy and acts as an antioxidant.

Vitamin A supplements may reduce the risk for certain types of cancer. Vitamin A influences cell...