• Night blindness
• Keratomalacia
• Pale, dry skin

! bgcolor="#ffeedd" colspan="2" | Excess symptoms

• Liver toxicity
• Dry skin
• Hair loss
• Teratological effects
• Osteoporosis (suspected, long-term)

! bgcolor="#ffddaa" colspan="2" | Common sources

• Liver
• Dairy products
• Darkly colored fruits
• Leafy vegetables

Vitamin A (Retinol)
General
Chemical formula	C20H30O
Molecular weight	286.456 g/mol
Vitamin properties
Solubility	Fat
RDA (adult male)	900 µg/day
RDA (adult female)	700 µg/day
RDA upper limit (adult male)	3,000 µg/day
RDA upper limit (adult female)	3,000 µg/day
Deficiency symptoms

Retinol, the dietary form of vitamin A, is a fat-soluble, antioxidant vitamin important in vision and bone growth. It belongs to the family of chemical compounds known as retinoids. Retinol is ingested in a precursor form; animal sources (milk and eggs) contain retinyl esters, whereas plants (carrots, spinach) contain pro-vitamin A carotenoids. Hydrolysis of retinyl esters results in retinol while pro-vitamin A carotenoids can be cleaved to produce retinal. Retinal, also known as retinaldehyde, can be reversibly reduced to produce retinol or it can be irreversibly oxidized to produce retinoic acid. The best described active retinoid metabolites are 11-cis-retinal and the all-trans and 9-cis-isomers of retinoic acid.

Discovery

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In 1913, Elmer McCollum, a biochemist at the University of Wisconsin, and colleague Marguerite Davis identified a fat-soluble nutrient in butterfat and cod liver oil. Their work confirmed that of Thomas Osborne and Lafayette Mendel, at Yale, which suggested a fat-soluble nutrient in butterfat, also in 1913 Semba RD. Vitamin A as "Anti-Infective" Therapy, 1920–1940. Journal of Nutrition. 1999;129:783-791. PMID 10203551. Full Text Available. Vitamin A was first synthesized in 1947.

More on [ Retinol ]

Vitamin A - Twitter Search

SKIN NUTRITION: Stretch Mark cream with Shea Butter, Vitamin A, E and C with added skin tightner (Professional Grad... http://bit.ly/8s6vTR
cheapshopping (shoppingdad.com) Fri, 25 Dec 2009 16:05:23 -0000
SKIN NUTRITION: Stretch Mark cream with Shea Butter, Vitamin A, E and C with added skin tightner (Professional Grad... http://bit.ly/8s6vTR
For Christmas I got De-Icer for my Bronco, Vitamin C and a UMD shot glass!! Other things too, but those were the most notable lol
LyndsieSmyser (Lyndsie Smyser) Fri, 25 Dec 2009 15:55:54 -0000
For Christmas I got De-Icer for my Bronco, Vitamin C and a UMD shot glass!! Other things too, but those were the most notable lol
tempted to pour my vitamin water on him but that would be a waste of vitamin water!
bethanybean (Bethany) Fri, 25 Dec 2009 15:45:35 -0000
tempted to pour my vitamin water on him but that would be a waste of vitamin water!
Vitamin C can knock out a cold right?!
lilcrazedkid (Lil Crazed) Fri, 25 Dec 2009 15:39:47 -0000
Vitamin C can knock out a cold right?!
#tvxq is.. a vitamin to the eye! ♥
heykimee (Kiiiiiim ★) Fri, 25 Dec 2009 15:38:12 -0000
#tvxq is.. a vitamin to the eye! ♥
Every vitamin I make comes from a food or plant source that your body would read as food @drdavesbest http://j.mp/DrDave
tanqSJ (TanqSJ at Marriott) Fri, 25 Dec 2009 15:36:49 -0000
Every vitamin I make comes from a food or plant source that your body would read as food @drdavesbest http://j.mp/DrDave

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