Vitamin A - Need & Benefits

Vitamin A and Provitamin A Carotenoids (Beta Carotene)

Vitamin A refers to a group of compounds known as retinoids with varying degrees of vitamin A activity; the predominant compound is retinol. Active vitamin A can be synthesized endogenously from carotenoid precursors. More than 500 carotenoids are known, but only approximately 10% of them have provitamin A activity. Among that 10% are β-carotene, α-carotene, and cryptoxanthin.

Vitamin A is incorporated into the rod and cone cells of the retina; in the rods, it is a structural constituent of rhodopsin and functions in night vision. Vitamin A also functions in the generation of epithelial cells, in the growth of bones and teeth, in reproduction (by several mechanisms), and in immune function.

Vitamin A Benefits

Vitamin A is Essential for growth, bone development, night vision, reproduction, and good healthy skin.

Source of vitamin A

Preformed vitamin A is found in animal products, such as liver, dairy products, eggs, and fish liver oilorgan meats, especially liver, and in fish, egg yolks, and fortified milk. Provitamin A carotenoids are also found in dark red, green, and yellow vegetables and fruits. Requires some dietary fat to be absorbed. Carotenoids are abundant in brightly colored fruits and vegetables.

Vitamin A is potentially taratogenic in high doses, and thus prenatal vitamins generally provide lower levels than do standard supplements.