Vitamin A

Last Updated: September 28 2022

Vitamin A refers to a group of compounds that serve important roles in modulating skin health, vision, gene transcription, and immune system functioning. Deficiencies, which are common in developing countries, can lead to impaired vision, dry skin and poor immunity.

Vitamin A is most often used for

Summary

Vitamin A is not a single compound but a group of chemical compounds that are structurally similar. These compounds include retinol, retinaldehyde, retinoic acid, and provitamin A caretenoids which include beta-carotene, alpha-carotene, gamma-carotene and cryptoxanthin. Retinol and beta-carotene are some of the most common forms of vitamin A found in food and supplements, with the former being found in animals and the latter in plants.

Vitamin A is involved in the modulation of skin health, vision, the immune system, and gene transcription. Different forms of vitamin A will serve different functions. For example, it is retinoic acid that is involved in gene transcription and the maintenance of skin health; it is retinaldehyde that binds certain proteins to the cones and rods of the eye, allowing the eye to function in low-light environments.

What else is Vitamin A known as?
Note that Vitamin A is also known as:
  • retinol
  • retinal
  • retinoic acid
  • tretinoin
  • beta-carotene
Dosage information

For topical application, the form of all-trans retinoic acid (Tretinoin) should be used in a facial cream/lotion containing it in the range of 0.01-0.10%, with the lowest concentration having low side-effects but less efficacy and 0.025-0.05% being the sweet spot. Topical application is once nightly.

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      References
      1.^Schreiber R, Taschler U, Preiss-Landl K, Wongsiriroj N, Zimmermann R, Lass ARetinyl ester hydrolases and their roles in vitamin A homeostasisBiochim Biophys Acta.(2012 Jan)
      2.^O'Byrne SM, Blaner WSRetinol and retinyl esters: biochemistry and physiologyJ Lipid Res.(2013 Jul)
      6.^Bauer EA, Seltzer JL, Eisen AZInhibition of collagen degradative enzymes by retinoic acid in vitroJ Am Acad Dermatol.(1982 Apr)
      8.^Kligman LH1, Schwartz E, Lesnik RH, Mezick JATopical tretinoin prevents corticosteroid-induced atrophy without lessening the anti-inflammatory effectCurr Probl Dermatol.(1993)
      10.^Kafi R1, Kwak HS, Schumacher WE, Cho S, Hanft VN, Hamilton TA, King AL, Neal JD, Varani J, Fisher GJ, Voorhees JJ, Kang SImprovement of naturally aged skin with vitamin A (retinol)Arch Dermatol.(2007 May)
      11.^Fisher GJ1, Wang ZQ, Datta SC, Varani J, Kang S, Voorhees JJPathophysiology of premature skin aging induced by ultraviolet lightN Engl J Med.(1997 Nov 13)
      12.^Fisher GJ1, Kang S, Varani J, Bata-Csorgo Z, Wan Y, Datta S, Voorhees JJMechanisms of photoaging and chronological skin agingArch Dermatol.(2002 Nov)
      13.^Griffiths CE1, Russman AN, Majmudar G, Singer RS, Hamilton TA, Voorhees JJRestoration of collagen formation in photodamaged human skin by tretinoin (retinoic acid)N Engl J Med.(1993 Aug 19)
      15.^Weiss JS1, Ellis CN, Headington JT, Tincoff T, Hamilton TA, Voorhees JJTopical tretinoin improves photoaged skin. A double-blind vehicle-controlled studyJAMA.(1988 Jan 22-29)
      17.^Griffiths CE1, Goldfarb MT, Finkel LJ, Roulia V, Bonawitz M, Hamilton TA, Ellis CN, Voorhees JJTopical tretinoin (retinoic acid) treatment of hyperpigmented lesions associated with photoaging in Chinese and Japanese patients: a vehicle-controlled trialJ Am Acad Dermatol.(1994 Jan)
      18.^Weinstein GD1, Nigra TP, Pochi PE, Savin RC, Allan A, Benik K, Jeffes E, Lufrano L, Thorne EGTopical tretinoin for treatment of photodamaged skin. A multicenter studyArch Dermatol.(1991 May)