Back Vitamien AF فيتامين Arabic ভিটামিন AS Vitamina AST Vitaminlər AZ Витаминдар BA Bitamina BCL Вітаміны BE Вітаміны BE-X-OLD Витамин Bulgarian
| Vitamin | |
|---|---|
| Drug class | |
 A bottle of B-complex vitamin pills | |
| Pronunciation | UK: /ˈvɪtəmɪn, ˈvaɪt-/ VIT-ə-min, VYTE-, US: /ˈvaɪtəmɪn/ VY-tə-min[1] |
| Legal status | |
| In Wikidata | |
Vitamins are organic molecules (or a set of closely related molecules called vitamers) that are essential to an organism in small quantities for proper metabolic function. Essential nutrients cannot be synthesized in the organism in sufficient quantities for survival, and therefore must be obtained through the diet. For example, vitamin C can be synthesized by some species but not by others; it is not considered a vitamin in the first instance but is in the second. Most vitamins are not single molecules, but groups of related molecules called vitamers. For example, there are eight vitamers of vitamin E: four tocopherols and four tocotrienols.
The term vitamin does not include the three other groups of essential nutrients: minerals, essential fatty acids, and essential amino acids.[2]
Major health organizations list thirteen vitamins:[3][4][5]
- Vitamin A (all-trans-retinols, all-trans-retinyl-esters, as well as all-trans-β-carotene and other provitamin A carotenoids)
- Vitamin B1 (thiamine)
- Vitamin B2 (riboflavin)
- Vitamin B3 (niacin)
- Vitamin B5 (pantothenic acid)
- Vitamin B6 (pyridoxine)
- Vitamin B7 (biotin)
- Vitamin B9 (folic acid and folates)
- Vitamin B12 (cobalamins)
- Vitamin C (ascorbic acid and ascorbates)
- Vitamin D (calciferols)
- Vitamin E (tocopherols and tocotrienols)
- Vitamin K (phylloquinones, menaquinones, and menadiones)
Some sources include a fourteenth, choline.[6]
Vitamins have diverse biochemical functions. Vitamin A acts as a regulator of cell and tissue growth and differentiation. Vitamin D provides a hormone-like function, regulating mineral metabolism for bones and other organs. The B complex vitamins function as enzyme cofactors (coenzymes) or the precursors for them. Vitamins C and E function as antioxidants.[7] Both deficient and excess intake of a vitamin can potentially cause clinically significant illness, although excess intake of water-soluble vitamins is less likely to do so.
All the vitamins were discovered between 1913 and 1948. Historically, when intake of vitamins from diet was lacking, the results were vitamin deficiency diseases. Then, starting in 1935, commercially produced tablets of yeast-extract vitamin B complex and semi-synthetic vitamin C became available.[8] This was followed in the 1950s by the mass production and marketing of vitamin supplements, including multivitamins, to prevent vitamin deficiencies in the general population.[8] Governments have mandated the addition of some vitamins to staple foods such as flour or milk, referred to as food fortification, to prevent deficiencies.[9] Recommendations for folic acid supplementation during pregnancy reduced risk of infant neural tube defects.[10]
- ^ Jones, Daniel (2011). Roach, Peter; Setter, Jane; Esling, John (eds.). Cambridge English Pronouncing Dictionary (18th ed.). Cambridge University Press. ISBN 978-0-521-15255-6.
- ^ Maton A, Hopkins J, McLaughlin CW, Johnson S, Warner MQ, LaHart D, Wright JD (1993). Human Biology and Health. Englewood Cliffs, NJ: Prentice Hall. ISBN 978-0-13-981176-0. OCLC 32308337.
- ^ "Vitamins and Minerals". National Institute on Aging. Retrieved 12 May 2020.
- ^ Vitamin and mineral requirements in human nutrition 2nd Edition. World Health Organization and Food and Agriculture Organization of the United Nations. 2004. pp. 340–341. ISBN 9241546123. Archived from the original on 12 December 2012.
- ^ Regulation (EC) No 1925/2006 of the European Parliament and of the Council of 20 December 2006 on the addition of vitamins and minerals and of certain other substances to foods
- ^ "Listing of vitamins". Harvard Health Publishing. 9 June 2009. Retrieved 12 May 2020.
- ^ Bender DA (2003). Nutritional biochemistry of the vitamins. Cambridge, UK: Cambridge University Press. ISBN 978-0-521-80388-5.
- ^ a b Cite error: The named reference
Pricewas invoked but never defined (see the help page). - ^ "Food Fortification Initiative". Food Fortification Initiative, Enhancing Grains for Better Lives. Archived from the original on 4 April 2017. Retrieved 18 August 2018.
- ^ Wilson RD, Wilson RD, Audibert F, Brock JA, Carroll J, Cartier L, et al. (June 2015). "Pre-conception Folic Acid and Multivitamin Supplementation for the Primary and Secondary Prevention of Neural Tube Defects and Other Folic Acid-Sensitive Congenital Anomalies". Journal of Obstetrics and Gynaecology Canada. 37 (6): 534–552. doi:10.1016/s1701-2163(15)30230-9. PMID 26334606.