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Vitamin A

Family of essential fat-soluble retinoids including retinol, retinal, and retinoic acid, plus provitamin A carotenoids, required for vision, immunity, epithelial integrity, growth, and reproduction.

Also: Retinoid, Retinol

Adult RDA is 900 μg RAE men, 700 μg RAE women. Deficiency causes xerophthalmia, night blindness (impaired rhodopsin regeneration), Bitot spots, and increased infectious disease mortality, especially in children. Vitamin A is delivered by chylomicrons as retinyl esters, stored in hepatic stellate cells, and mobilized as retinol bound to retinol-binding protein. Excess preformed vitamin A (not β-carotene) is teratogenic and hepatotoxic; UL is 3,000 μg/d in adults.

How each textbook covers it

  • duyff-complete-food-and-nutrition-guide-5e

  • Modern Nutrition in Health and Disease, 12th ed. — Ch 17: Vitamin A

    Adult RDA is 900 μg RAE men, 700 μg RAE women. Deficiency causes xerophthalmia, night blindness (impaired rhodopsin regeneration), Bitot spots, and increased infectious disease mortality, especially in children. Vitamin A is delivered by chylomicrons as retinyl esters, stored in hepatic stellate cells, and mobilized as retinol bound to retinol-binding protein. Excess preformed vitamin A (not β-carotene) is teratogenic and hepatotoxic; UL is 3,000 μg/d in adults.

Related terms

Carotenoids, RAE, RAR, Xerophthalmia