vitamin A


vitamin A
= retinol
a fat-soluble vitamin that occurs preformed in foods of animal origin (especially milk products, egg yolk, and liver) and is formed in the body from the pigment β-carotene, present in some vegetable foods (for example cabbage, lettuce, and carrots). Retinol is essential for growth, vision in dim light, and the maintenance of soft mucous tissue. A deficiency causes stunted growth, night blindness, xerophthalmia, keratomalacia, and eventual blindness. The recommended daily intake is 750 μg retinol equivalents for an adult (1 μg retinol equivalent = 1 μg retinol or 6 μg β-carotene).

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