Misplaced Pages

Latest revision as of 21:53, 2 November 2024

Vitamin
Drug class
A bottle of B-complex vitamin pills
Pronunciation	UK: /ˈvɪtəmɪn, ˈvaɪt-/ VIT-ə-min, VYTE-, US: /ˈvaɪtəmɪn/ VY-tə-min
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.

Major health organizations list thirteen vitamins:

• 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.

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. 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. 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. Governments have mandated the addition of some vitamins to staple foods such as flour or milk, referred to as food fortification, to prevent deficiencies. Recommendations for folic acid supplementation during pregnancy reduced risk of infant neural tube defects.

List of vitamins

History

The value of eating certain foods to maintain health was recognized long before vitamins were identified. The ancient Egyptians knew that feeding liver to a person may help with night blindness, an illness now known to be caused by a vitamin A deficiency. The advance of ocean voyages during the Age of Discovery resulted in prolonged periods without access to fresh fruits and vegetables, and made illnesses from vitamin deficiency common among ships' crews.

In 1747, the Scottish surgeon James Lind discovered that citrus foods helped prevent scurvy, a particularly deadly disease in which collagen is not properly formed, causing poor wound healing, bleeding of the gums, severe pain, and death. In 1753, Lind published his Treatise on the Scurvy, which recommended using lemons and limes to avoid scurvy, which was adopted by the British Royal Navy. This led to the nickname limey for British sailors. However, during the 19th century, limes grown in the West Indies were substituted for lemons; these were subsequently found to be much lower in vitamin C. As a result, Arctic expeditions continued to be plagued by scurvy and other deficiency diseases. In the early 20th century, when Robert Falcon Scott made his two expeditions to the Antarctic, the prevailing medical theory was that scurvy was caused by "tainted" canned food.

In 1881, Russian medical doctor Nikolai Lunin studied the effects of scurvy at the University of Tartu. He fed mice an artificial mixture of all the separate constituents of milk known at that time, namely the proteins, fats, carbohydrates, and salts. The mice that received only the individual constituents died, while the mice fed by milk itself developed normally. He made a conclusion that "a natural food such as milk must therefore contain, besides these known principal ingredients, small quantities of unknown substances essential to life." However, his conclusions were rejected by his advisor, Gustav von Bunge. A similar result by Cornelis Adrianus Pekelharing appeared in Dutch medical journal Nederlands Tijdschrift voor Geneeskunde in 1905, but it was not widely reported.

In East Asia, where polished white rice was the common staple food of the middle class, beriberi resulting from lack of vitamin B₁ was endemic. In 1884, Takaki Kanehiro, a British-trained medical doctor of the Imperial Japanese Navy, observed that beriberi was endemic among low-ranking crew who often ate nothing but rice, but not among officers who consumed a Western-style diet. With the support of the Japanese navy, he experimented using crews of two battleships; one crew was fed only white rice, while the other was fed a diet of meat, fish, barley, rice, and beans. The group that ate only white rice documented 161 crew members with beriberi and 25 deaths, while the latter group had only 14 cases of beriberi and no deaths. This convinced Takaki and the Japanese Navy that diet was the cause of beriberi, but they mistakenly believed that sufficient amounts of protein prevented it. That diseases could result from some dietary deficiencies was further investigated by Christiaan Eijkman, who in 1897 discovered that feeding unpolished rice instead of the polished variety to chickens helped to prevent a kind of polyneuritis that was the equivalent of beriberi. The following year, Frederick Hopkins postulated that some foods contained "accessory factors" – in addition to proteins, carbohydrates, fats etc. – that are necessary for the functions of the human body.

"Vitamine" to vitamin

In 1910, the first vitamin complex was isolated by Japanese scientist Umetaro Suzuki, who succeeded in extracting a water-soluble complex of micronutrients from rice bran and named it aberic acid (later Orizanin). He published this discovery in a Japanese scientific journal. When the article was translated into German, the translation failed to state that it was a newly discovered nutrient, a claim made in the original Japanese article, and hence his discovery failed to gain publicity. In 1912 Polish-born biochemist Casimir Funk, working in London, isolated the same complex of micronutrients and proposed the complex be named "vitamine". It was later to be known as vitamin B₃ (niacin), though he described it as "anti-beri-beri-factor" (which would today be called thiamine or vitamin B₁). Funk proposed the hypothesis that other diseases, such as rickets, pellagra, coeliac disease, and scurvy could also be cured by vitamins. Max Nierenstein a friend and Reader of Biochemistry at Bristol University reportedly suggested the "vitamine" name (from "vital amine"). The name soon became synonymous with Hopkins' "accessory factors", and, by the time it was shown that not all vitamins are amines, the word was already ubiquitous. In 1920, Jack Cecil Drummond proposed that the final "e" be dropped to deemphasize the "amine" reference, hence "vitamin", after researchers began to suspect that not all "vitamines" (in particular, vitamin A) have an amine component.

Nobel Prizes for vitamin research

The Nobel Prize for Chemistry for 1928 was awarded to Adolf Windaus "for his studies on the constitution of the sterols and their connection with vitamins", the first person to receive an award mentioning vitamins, even though it was not specifically about vitamin D.

The Nobel Prize in Physiology or Medicine for 1929 was awarded to Christiaan Eijkman and Frederick Gowland Hopkins for their contributions to the discovery of vitamins. Thirty-five years earlier, Eijkman had observed that chickens fed polished white rice developed neurological symptoms similar to those observed in military sailors and soldiers fed a rice-based diet, and that the symptoms were reversed when the chickens were switched to whole-grain rice. He called this "the anti-beriberi factor", which was later identified as vitamin B₁, thiamine.

In 1930, Paul Karrer elucidated the correct structure for beta-carotene, the main precursor of vitamin A, and identified other carotenoids. Karrer and Norman Haworth confirmed Albert Szent-Györgyi's discovery of ascorbic acid and made significant contributions to the chemistry of flavins, which led to the identification of lactoflavin. For their investigations on carotenoids, flavins and vitamins A and B₂, they both received the Nobel Prize in Chemistry in 1937.

In 1931, Albert Szent-Györgyi and a fellow researcher Joseph Svirbely suspected that "hexuronic acid" was actually vitamin C, and gave a sample to Charles Glen King, who proved its activity counter to scurvy in his long-established guinea pig scorbutic assay. In 1937, Szent-Györgyi was awarded the Nobel Prize in Physiology or Medicine for his discovery. In 1943, Edward Adelbert Doisy and Henrik Dam were awarded the Nobel Prize in Physiology or Medicine for their discovery of vitamin K and its chemical structure.

In 1938, Richard Kuhn was awarded the Nobel Prize in Chemistry for his work on carotenoids and vitamins, specifically B₂ and B₆.

Five people have been awarded Nobel Prizes for direct and indirect studies of vitamin B₁₂: George Whipple, George Minot and William P. Murphy (1934), Alexander R. Todd (1957), and Dorothy Hodgkin (1964).

In 1967, George Wald, Ragnar Granit and Haldan Keffer Hartline were awarded the Nobel Prize in Physiology and Medicine "...for their discoveries concerning the primary physiological and chemical visual processes in the eye." Wald's contribution was discovering the role vitamin A had in the process.

History of promotional marketing

Once discovered, vitamins were actively promoted in articles and advertisements in McCall's, Good Housekeeping, and other media outlets. Marketers enthusiastically promoted cod-liver oil, a source of vitamin D, as "bottled sunshine", and bananas as a "natural vitality food". They promoted foods such as yeast cakes, a source of B vitamins, on the basis of scientifically determined nutritional value, rather than taste or appearance. In 1942, when flour enrichment with nicotinic acid began, a headline in the popular press said "Tobacco in Your Bread." In response, the Council on Foods and Nutrition of the American Medical Association approved of the Food and Nutrition Board's new names niacin and niacin amide for use primarily by non-scientists. It was thought appropriate to choose a name to dissociate nicotinic acid from nicotine, to avoid the perception that vitamins or niacin-rich food contains nicotine, or that cigarettes contain vitamins. The resulting name niacin was derived from nicotinic acid + vitamin. Researchers also focused on the need to ensure adequate nutrition, especially to compensate for what was lost in the manufacture of processed foods.

Robert W. Yoder is credited with first using the term vitamania, in 1942, to describe the appeal of relying on nutritional supplements rather than on obtaining vitamins from a varied diet of foods. The continuing preoccupation with a healthy lifestyle led to an obsessive consumption of vitamins and multi-vitamins, the beneficial effects of which are questionable. As one example, in the 1950s, the Wonder Bread company sponsored the Howdy Doody television show, with host Buffalo Bob Smith telling the audience, "Wonder Bread builds strong bodies 8 ways", referring to the number of added nutrients.

Etymology

The term "vitamin" was derived from "vitamine", a portmanteau coined in 1912 by the biochemist Casimir Funk while working at the Lister Institute of Preventive Medicine. Funk created the name from vital and amine, because it appeared that these organic micronutrient food factors that prevent beriberi and perhaps other similar dietary-deficiency diseases were required for life, hence "vital", and were chemical amines, hence "amine". This was true of thiamine, but after it was found that vitamin C and other such micronutrients were not amines, the word was shortened to "vitamin" in English.

Classification

Vitamins are classified as either water-soluble or fat-soluble. In humans there are 13 vitamins: 4 fat-soluble (A, D, E, and K) and 9 water-soluble (8 B vitamins and vitamin C). Water-soluble vitamins dissolve easily in water and, in general, are readily excreted from the body, to the degree that urinary output is a strong predictor of vitamin consumption. Because they are not as readily stored, more consistent intake is important. Fat-soluble vitamins are absorbed through the gastrointestinal tract with the help of lipids (fats). Vitamins A and D can accumulate in the body, which can result in dangerous hypervitaminosis. Fat-soluble vitamin deficiency due to malabsorption is of particular significance in cystic fibrosis.

Anti-vitamins

Anti-vitamins are chemical compounds that inhibit the absorption or actions of vitamins. For example, avidin is a protein in raw egg whites that inhibits the absorption of biotin; it is deactivated by cooking. Pyrithiamine, a synthetic compound, has a molecular structure similar to thiamine, vitamin B₁, and inhibits the enzymes that use thiamine.

Biochemical functions

Each vitamin is typically used in multiple reactions, and therefore most have multiple functions.

On fetal growth and childhood development

Vitamins are essential for the normal growth and development of a multicellular organism. Using the genetic blueprint inherited from its parents, a fetus develops from the nutrients it absorbs. It requires certain vitamins and minerals to be present at certain times. These nutrients facilitate the chemical reactions that produce among other things, skin, bone, and muscle. If there is serious deficiency in one or more of these nutrients, a child may develop a deficiency disease. Even minor deficiencies may cause permanent damage.

On adult health maintenance

Once growth and development are completed, vitamins remain essential nutrients for the healthy maintenance of the cells, tissues, and organs that make up a multicellular organism; they also enable a multicellular life form to efficiently use chemical energy provided by food it eats, and to help process the proteins, carbohydrates, and fats required for cellular respiration.

Intake

Sources

For the most part, vitamins are obtained from the diet, but some are acquired by other means: for example, microorganisms in the gut flora produce vitamin K and biotin; and one form of vitamin D is synthesized in skin cells when they are exposed to a certain wavelength of ultraviolet light present in sunlight. Humans can produce some vitamins from precursors they consume: for example, vitamin A is synthesized from beta carotene; and niacin is synthesized from the amino acid tryptophan. Vitamin C can be synthesized by some species but not by others. Vitamin B₁₂ is the only vitamin or nutrient not available from plant sources. The Food Fortification Initiative lists countries which have mandatory fortification programs for vitamins folic acid, niacin, vitamin A and vitamins B₁, B₂ and B₁₂.

Deficient intake

The body's stores for different vitamins vary widely; vitamins A, D, and B₁₂ are stored in significant amounts, mainly in the liver, and an adult's diet may be deficient in vitamins A and D for many months and B₁₂ in some cases for years, before developing a deficiency condition. However, vitamin B₃ (niacin and niacinamide) is not stored in significant amounts, so stores may last only a couple of weeks. For vitamin C, the first symptoms of scurvy in experimental studies of complete vitamin C deprivation in humans have varied widely, from a month to more than six months, depending on previous dietary history that determined body stores.

Deficiencies of vitamins are classified as either primary or secondary. A primary deficiency occurs when an organism does not get enough of the vitamin in its food. A secondary deficiency may be due to an underlying disorder that prevents or limits the absorption or use of the vitamin, due to a "lifestyle factor", such as smoking, excessive alcohol consumption, or the use of medications that interfere with the absorption or use of the vitamin. People who eat a varied diet are unlikely to develop a severe primary vitamin deficiency, but may be consuming less than the recommended amounts; a national food and supplement survey conducted in the US over 2003–2006 reported that over 90% of individuals who did not consume vitamin supplements were found to have inadequate levels of some of the essential vitamins, notably vitamins D and E.

Well-researched human vitamin deficiencies involve thiamine (beriberi), niacin (pellagra), vitamin C (scurvy), folate (neural tube defects) and vitamin D (rickets). In much of the developed world these deficiencies are rare due to an adequate supply of food and the addition of vitamins to common foods. In addition to these classical vitamin deficiency diseases, some evidence has also suggested links between vitamin deficiency and a number of different disorders.

Excess intake

Some vitamins have documented acute or chronic toxicity at larger intakes, which is referred to as hypertoxicity. The European Union and the governments of several countries have established Tolerable upper intake levels (ULs) for those vitamins which have documented toxicity (see table). The likelihood of consuming too much of any vitamin from food is remote, but excessive intake (vitamin poisoning) from dietary supplements does occur. In 2016, overdose exposure to all formulations of vitamins and multi-vitamin/mineral formulations was reported by 63,931 individuals to the American Association of Poison Control Centers with 72% of these exposures in children under the age of five. In the US, analysis of a national diet and supplement survey reported that about 7% of adult supplement users exceeded the UL for folate and 5% of those older than age 50 years exceeded the UL for vitamin A.

Effects of cooking

The USDA has conducted extensive studies on the percentage losses of various nutrients from food types and cooking methods. Some vitamins may become more "bio-available" – that is, usable by the body – when foods are cooked. The table below shows whether various vitamins are susceptible to loss from heat—such as heat from boiling, steaming, frying, etc. The effect of cutting vegetables can be seen from exposure to air and light. Water-soluble vitamins such as B and C dissolve into the water when a vegetable is boiled, and are then lost when the water is discarded.

Recommended levels

In setting human nutrient guidelines, government organizations do not necessarily agree on amounts needed to avoid deficiency or maximum amounts to avoid the risk of toxicity. For example, for vitamin C, recommended intakes range from 40 mg/day in India to 155 mg/day for the European Union. The table below shows U.S. Estimated Average Requirements (EARs) and Recommended Dietary Allowances (RDAs) for vitamins, PRIs for the European Union (same concept as RDAs), followed by what three government organizations deem to be the safe upper intake. RDAs are set higher than EARs to cover people with higher than average needs. Adequate Intakes (AIs) are set when there is not sufficient information to establish EARs and RDAs. Governments are slow to revise information of this nature. For the U.S. values, with the exception of calcium and vitamin D, all of the data date to 1997–2004.

All values are consumption per day:

EAR US Estimated Average Requirements.

RDA US Recommended Dietary Allowances; higher for adults than for children, and may be even higher for women who are pregnant or lactating.

AI US and EFSA Adequate Intake; AIs established when there is not sufficient information to set EARs and RDAs.

PRI Population Reference Intake is European Union equivalent of RDA; higher for adults than for children, and may be even higher for women who are pregnant or lactating. For Thiamin and Niacin the PRIs are expressed as amounts per MJ of calories consumed. MJ = megajoule = 239 food calories.

UL or Upper Limit Tolerable upper intake levels.

ND ULs have not been determined.

NE EARs have not been established.

Supplementation

In those who are otherwise healthy, there is little evidence that supplements have any benefits with respect to cancer or heart disease. Vitamin A and E supplements not only provide no health benefits for generally healthy individuals, but they may increase mortality, though the two large studies that support this conclusion included smokers for whom it was already known that beta-carotene supplements can be harmful. A 2018 meta-analysis found no evidence that intake of vitamin D or calcium for community-dwelling elderly people reduced bone fractures.

Europe has regulations that define limits of vitamin (and mineral) dosages for their safe use as dietary supplements. Most vitamins that are sold as dietary supplements are not supposed to exceed a maximum daily dosage referred to as the tolerable upper intake level (UL or Upper Limit). Vitamin products above these regulatory limits are not considered supplements and should be registered as prescription or non-prescription (over-the-counter drugs) due to their potential side effects. The European Union, United States and Japan establish ULs.

Dietary supplements often contain vitamins, but may also include other ingredients, such as minerals, herbs, and botanicals. Scientific evidence supports the benefits of dietary supplements for persons with certain health conditions. In some cases, vitamin supplements may have unwanted effects, especially if taken before surgery, with other dietary supplements or medicines, or if the person taking them has certain health conditions. They may also contain levels of vitamins many times higher, and in different forms, than one may ingest through food.

Governmental regulation

Most countries place dietary supplements in a special category under the general umbrella of foods, not drugs. As a result, the manufacturer, and not the government, has the responsibility of ensuring that its dietary supplement products are safe before they are marketed. Regulation of supplements varies widely by country. In the United States, a dietary supplement is defined under the Dietary Supplement Health and Education Act of 1994. There is no FDA approval process for dietary supplements, and no requirement that manufacturers prove the safety or efficacy of supplements introduced before 1994. The Food and Drug Administration must rely on its Adverse Event Reporting System to monitor adverse events that occur with supplements.

In 2007, the US Code of Federal Regulations (CFR) Title 21, part III took effect, regulating Good Manufacturing Practices (GMPs) in the manufacturing, packaging, labeling, or holding operations for dietary supplements. Even though product registration is not required, these regulations mandate production and quality control standards (including testing for identity, purity and adulterations) for dietary supplements. In the European Union, the Food Supplements Directive requires that only those supplements that have been proven safe can be sold without a prescription. For most vitamins, pharmacopoeial standards have been established. In the United States, the United States Pharmacopeia (USP) sets standards for the most commonly used vitamins and preparations thereof. Likewise, monographs of the European Pharmacopoeia (Ph.Eur.) regulate aspects of identity and purity for vitamins on the European market.

Naming

The reason that the set of vitamins skips directly from E to K is that the vitamins corresponding to letters F–J were either reclassified over time, discarded as false leads, or renamed because of their relationship to vitamin B, which became a complex of vitamins.

The Danish-speaking scientists who isolated and described vitamin K (in addition to naming it as such) did so because the vitamin is intimately involved in the coagulation of blood following wounding (from the Danish word Koagulation). At the time, most (but not all) of the letters from F through to J were already designated, so the use of the letter K was considered quite reasonable. The table Nomenclature of reclassified vitamins lists chemicals that had previously been classified as vitamins, as well as the earlier names of vitamins that later became part of the B-complex.

The missing numbered B vitamins were reclassified or determined not to be vitamins. For example, B₉ is folic acid and five of the folates are in the range B₁₁ through B₁₆. Others, such as PABA (formerly B₁₀), are biologically inactive, toxic, or with unclassifiable effects in humans, or not generally recognised as vitamins by science, such as the highest-numbered, which some naturopath practitioners call B₂₁ and B₂₂. There are also lettered B substances (e.g., B_m) listed at B vitamins that are not recognized as vitamins. There are other "D vitamins" now recognised as other substances, which some sources of the same type number up to D₇. The controversial cancer treatment laetrile was at one point lettered as vitamin B₁₇. There appears to be no consensus on the existence of substances that may have at one time been named as vitamins Q, R, T, V, W, X, Y or Z.

"Vitamin N" is a term popularized for the mental health benefits of spending time in nature settings. "Vitamin I" is slang among athletes for frequent/daily consumption of ibuprofen as a pain-relieving treatment.

See also

• Vitamin deficiency
• Hypervitaminosis
• Human nutrition

References

1. 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.
2. 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.
3. "Vitamins and Minerals". National Institute on Aging. Retrieved 12 May 2020.
4. 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.
5. 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
6. "Listing of vitamins". Harvard Health Publishing. 9 June 2009. Retrieved 12 May 2020.
7. ^ Bender DA (2003). Nutritional biochemistry of the vitamins. Cambridge, UK: Cambridge University Press. ISBN 978-0-521-80388-5.
8. ^ Price C (2015). Vitamania: Our obsessive quest for nutritional perfection. Penguin Press. ISBN 978-1594205040.
9. ^ "Food Fortification Initiative". Food Fortification Initiative, Enhancing Grains for Better Lives. Archived from the original on 4 April 2017. Retrieved 18 August 2018.
10. ^ 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.
11. ^ Dietary Reference Intakes (DRIs) Archived 11 September 2018 at the Wayback Machine Food and Nutrition Board, Institute of Medicine, National Academies
12. ^ "Vitamin A: Fact Sheet for Health Professionals". National Institute of Health: Office of Dietary Supplements. 5 June 2013. Archived from the original on 23 September 2009. Retrieved 3 August 2013.
13. "Thiamin, vitamin B1: MedlinePlus Supplements". U.S. Department of Health and Human Services, National Institutes of Health.
14. Hardman, J.G.; et al., eds. (2001). Goodman and Gilman's Pharmacological Basis of Therapeutics (10th ed.). McGraw-Hill. p. 992. ISBN 978-0071354691.
15. "Pantothenic acid, dexpanthenol: MedlinePlus Supplements". MedlinePlus. Retrieved 5 October 2009.
16. Vitamin and Mineral Supplement Fact Sheets Vitamin B6 Archived 23 September 2009 at the Wayback Machine. Dietary-supplements.info.nih.gov (15 September 2011). Retrieved on 3 August 2013.
17. Institute of Medicine (1998). "Vitamin B₆". Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline. Washington, DC: The National Academies Press. pp. 150–195. doi:10.17226/6015. ISBN 978-0-309-06554-2. LCCN 00028380. OCLC 475527045. PMID 23193625.
18. Vitamin and Mineral Supplement Fact Sheets Vitamin B12 Archived 23 September 2009 at the Wayback Machine. Dietary-supplements.info.nih.gov (24 June 2011). Retrieved on 3 August 2013.
19. Vitamins and minerals (3 March 2017). Retrieved on 2 June 2020.
20. ^ The Merck Manual: Nutritional Disorders: Vitamin Introduction Please select specific vitamins from the list at the top of the page.
21. Gaby AR (2005). "Does vitamin E cause congestive heart failure? (Literature Review & Commentary)". Townsend Letter for Doctors and Patients. Archived from the original on 10 September 2016.
22. Higdon J (2011). "Vitamin E recommendations". Linus Pauling Institute's Micronutrient Information Center.
23. Rohde LE, de Assis MC, Rabelo ER (January 2007). "Dietary vitamin K intake and anticoagulation in elderly patients". Current Opinion in Clinical Nutrition and Metabolic Care. 10 (1): 120–124. doi:10.1097/MCO.0b013e328011c46c. PMID 17143047. S2CID 20484616.
24. ^ Jack Challem (1997)."The Past, Present and Future of Vitamins" Archived 30 November 2005 at the Wayback Machine
25. Jacob RA (1996). "Introduction: Three Eras of Vitamin C Discovery". Three eras of vitamin C discovery. Subcellular Biochemistry. Vol. 25. pp. 1–16. doi:10.1007/978-1-4613-0325-1_1. ISBN 978-1-4613-7998-0. PMID 8821966.
26. Kögl F, Tönnis B (1936). "Über das Bios-Problem. Darstellung von krystallisiertem Biotin aus Eigelb. 20. Mitteilung über pflanzliche Wachstumsstoffe". Hoppe-Seyler's Zeitschrift für Physiologische Chemie. 242 (1–2): 43–73. doi:10.1515/bchm2.1936.242.1-2.43.
27. "The relative content of antiscorbutic principle in limes and lemons, together with some new facts and some old observations concerning the value of "lime juice" in the prevention of scurvy". The Lancet. 192 (4970): 735–738. 1918. doi:10.1016/S0140-6736(00)59026-6.
28. Lewis HE (January 1972). "Medical aspects of polar exploration: sixtieth anniversary of Scott's last expedition. State of knowledge about scurvy in 1911". Proceedings of the Royal Society of Medicine. 65 (1): 39–42. doi:10.1177/003591577206500116. PMC 1644345. PMID 4552518.
29. ^ Gratzer W (2006). "9. The quarry run to earth". Terrors of the table: the curious history of nutrition. Oxford: Oxford University Press. ISBN 978-0199205639. Retrieved 5 November 2015.
30. Semba RD (April 1999). "Vitamin A as "anti-infective" therapy, 1920–1940". The Journal of Nutrition. 129 (4): 783–791. doi:10.1093/jn/129.4.783. PMID 10203551.
31. ^ Rosenfeld L (April 1997). "Vitamine – vitamin. The early years of discovery". Clinical Chemistry. 43 (4): 680–685. doi:10.1093/clinchem/43.4.680. PMID 9105273.
32. ^ Wendt D (2015). "Packed full of questions: Who benefits from dietary supplements?". Distillations Magazine. 1 (3): 41–45. Retrieved 22 March 2018.
33. Suzuki, U.; Shimamura, T. (1911). "Active constituent of rice grits preventing bird polyneuritis". Tokyo Kagaku Kaishi. 32: 4–7, 144–146, 335–358. doi:10.1246/nikkashi1880.32.4.
34. ^ Funk C (1912). "The etiology of the deficiency diseases. Beri-beri, polyneuritis in birds, epidemic dropsy, scurvy, experimental scurvy in animals, infantile scurvy, ship beri-beri, pellagra". Journal of State Medicine. 20: 341–368. The word "vitamine" is coined on p. 342: "It is now known that all these diseases, with the exception of pellagra, can be prevented and cured by the addition of certain preventative substances; the deficient substances, which are of the nature of organic bases, we will call "vitamines"; and we will speak of a beri-beri or scurvy vitamine, which means a substance preventing the special disease."
35. ^ Combs G (2008). "Discovery of Vitamins". The vitamins: fundamental aspects in nutrition and health. Elsevier. ISBN 9780121834937.
36. Funk, C. and Dubin, H. E. (1922). The Vitamines. Baltimore: Williams and Wilkins Company.
37. Wolf G (June 2004). "The discovery of vitamin D: the contribution of Adolf Windaus". The Journal of Nutrition. 134 (6): 1299–1302. doi:10.1093/jn/134.6.1299. PMID 15173387.
38. ^ Carpenter K (22 June 2004). "The Nobel Prize and the Discovery of Vitamins". Nobelprize.org. Retrieved 5 October 2009.
39. "Paul Karrer-Biographical". Nobelprize.org. Retrieved 8 January 2013.
40. "The Nobel Prize in Chemistry 1938". Nobelprize.org. Retrieved 5 July 2018.
41. "The Nobel Prize and the Discovery of Vitamins". www.nobelprize.org. Archived from the original on 16 January 2018. Retrieved 15 February 2018.
42. "The Nobel Prize in Physiology or Medicine 1967". Nobel Foundation. Archived from the original on 4 December 2013. Retrieved 28 July 2007.
43. ^ Price C (Fall 2015). "The healing power of compressed yeast". Distillations Magazine. 1 (3): 17–23. Retrieved 20 March 2018.
44. "Niacin and Niacin Amide". Journal of the American Medical Association. 118 (10): 819. 7 March 1942. doi:10.1001/jama.1942.02830100049011.
45. "Niacin and Nicotinic Acid". Journal of the American Medical Association. 118 (10): 823. 7 March 1942. doi:10.1001/jama.1942.02830100053014.
46. Kelly K (27 October 2021). "Wonder Bread: The Most Famous White Bread". America Comes Alive. Retrieved 26 February 2022.
47. Fukuwatari T, Shibata K (June 2008). "Urinary water-soluble vitamins and their metabolite contents as nutritional markers for evaluating vitamin intakes in young Japanese women". Journal of Nutritional Science and Vitaminology. 54 (3): 223–229. doi:10.3177/jnsv.54.223. PMID 18635909.
48. Bellows L, Moore R. "Water-Soluble Vitamins". Colorado State University. Archived from the original on 25 September 2015. Retrieved 7 December 2008.
49. Maqbool A, Stallings VA (November 2008). "Update on fat-soluble vitamins in cystic fibrosis". Current Opinion in Pulmonary Medicine. 14 (6): 574–581. doi:10.1097/MCP.0b013e3283136787. PMID 18812835. S2CID 37143703.
50. Roth KS (September 1981). "Biotin in clinical medicine—a review". The American Journal of Clinical Nutrition. 34 (9): 1967–1974. doi:10.1093/ajcn/34.9.1967. PMID 6116428.
51. Rindi G, Perri V (July 1961). "Uptake of pyrithiamine by tissue of rats". The Biochemical Journal. 80 (1): 214–216. doi:10.1042/bj0800214. PMC 1243973. PMID 13741739.
52. Kutsky, R.J. (1973). Handbook of Vitamins and Hormones. New York: Van Nostrand Reinhold, ISBN 0-442-24549-1
53. Gavrilov, Leonid A. (10 February 2003) "Pieces of the Puzzle: Aging Research Today and Tomorrow". fightaging.org
54. Institute of Medicine (1998). "Niacin". Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline. Washington, DC: The National Academies Press. pp. 123–149. ISBN 978-0-309-06554-2. Retrieved 29 August 2018.
55. Pemberton J (June 2006). "Medical experiments carried out in Sheffield on conscientious objectors to military service during the 1939–45 war". International Journal of Epidemiology. 35 (3): 556–558. doi:10.1093/ije/dyl020. PMID 16510534.
56. ^ Bailey RL, Fulgoni VL, Keast DR, Dwyer JT (May 2012). "Examination of vitamin intakes among US adults by dietary supplement use". Journal of the Academy of Nutrition and Dietetics. 112 (5): 657–663.e4. doi:10.1016/j.jand.2012.01.026. PMC 3593649. PMID 22709770.
57. Lakhan SE, Vieira KF (January 2008). "Nutritional therapies for mental disorders". Nutrition Journal. 7: 2. doi:10.1186/1475-2891-7-2. PMC 2248201. PMID 18208598.
58. Boy E, Mannar V, Pandav C, de Benoist B, Viteri F, Fontaine O, Hotz C (May 2009). "Achievements, challenges, and promising new approaches in vitamin and mineral deficiency control". Nutrition Reviews. 67 (Suppl 1): S24–S30. doi:10.1111/j.1753-4887.2009.00155.x. PMID 19453674.
59. ^ Tolerable Upper Intake Levels For Vitamins And Minerals (PDF), European Food Safety Authority, 2006
60. ^ Dietary Reference Intakes for Japanese (2010) National Institute of Health and Nutrition, Japan
61. Gummin DD, Mowry JB, Spyker DA, Brooks DE, Fraser MO, Banner W (December 2017). "2016 Annual Report of the American Association of Poison Control Centers' National Poison Data System (NPDS): 34th Annual Report". Clinical Toxicology. 55 (10): 1072–1252. doi:10.1080/15563650.2017.1388087. PMID 29185815. S2CID 28547821.
62. "USDA Table of Nutrient Retention Factors, Release 6" (PDF). USDA. USDA. December 2007.
63. Comparison of Vitamin Levels in Raw Foods vs. Cooked Foods. Beyondveg.com. Retrieved on 3 August 2013.
64. Effects of Cooking on Vitamins (Table). Beyondveg.com. Retrieved on 3 August 2013.
65. "Nutrient Requirements and Recommended Dietary Allowances for Indians: A Report of the Expert Group of the Indian Council of Medical Research" (PDF). 2009. pp. 283–295. Archived (PDF) from the original on 15 June 2016.
66. ^ "Overview on Dietary Reference Values for the EU population as derived by the EFSA Panel on Dietetic Products, Nutrition and Allergies" (PDF). 2017. Archived (PDF) from the original on 28 August 2017.
67. Dietary Reference Intakes: The Essential Guide to Nutrient Requirements, published by the Institute of Medicine's Food and Nutrition Board, currently available online at "DRI Reports". Archived from the original on 5 July 2014. Retrieved 14 July 2014.
68. Fortmann SP, Burda BU, Senger CA, Lin JS, Whitlock EP (December 2013). "Vitamin and mineral supplements in the primary prevention of cardiovascular disease and cancer: An updated systematic evidence review for the U.S. Preventive Services Task Force". Annals of Internal Medicine. 159 (12): 824–834. doi:10.7326/0003-4819-159-12-201312170-00729. PMID 24217421.
69. ^ Moyer VA (April 2014). "Vitamin, mineral, and multivitamin supplements for the primary prevention of cardiovascular disease and cancer: U.S. Preventive services Task Force recommendation statement". Annals of Internal Medicine. 160 (8): 558–564. doi:10.7326/M14-0198. PMID 24566474.
70. Jenkins DJ, Spence JD, Giovannucci EL, Kim YI, Josse R, Vieth R, et al. (June 2018). "Supplemental Vitamins and Minerals for CVD Prevention and Treatment". Journal of the American College of Cardiology. 71 (22): 2570–2584. doi:10.1016/j.jacc.2018.04.020. PMID 29852980.
71. Bjelakovic G, Nikolova D, Gluud LL, Simonetti RG, Gluud C (February 2007). "Mortality in randomized trials of antioxidant supplements for primary and secondary prevention: systematic review and meta-analysis". JAMA. 297 (8): 842–857. doi:10.1001/jama.297.8.842. PMID 17327526.
72. Zhao JG, Zeng XT, Wang J, Liu L (December 2017). "Association Between Calcium or Vitamin D Supplementation and Fracture Incidence in Community-Dwelling Older Adults: A Systematic Review and Meta-analysis". JAMA. 318 (24): 2466–2482. doi:10.1001/jama.2017.19344. PMC 5820727. PMID 29279934.
73. ^ Use and Safety of Dietary Supplements Archived 27 March 2019 at the Wayback Machine NIH office of Dietary Supplements.
74. Legislation. Fda.gov (15 September 2009). Retrieved on 12 November 2010.
75. "Adverse Event Reporting System (AERS)". FDA. 20 August 2009. Retrieved 12 November 2010.
76. U.S. Food and Drug Administration. CFR – Code of Federal Regulations Title 21. Retrieved 16 February 2014.
77. Directive 2002/46/EC of the European Parliament and of the Council of 10 June 2002 on the approximation of the laws of the Member States relating to food supplements
78. ^ Bennett D. "Every Vitamin Page" (PDF). All Vitamins and Pseudo-Vitamins. Archived from the original (PDF) on 24 October 2019. Retrieved 24 July 2008.
79. ^ Davidson, Michael W. (2004) Anthranilic Acid (Vitamin L) Florida State University. Retrieved 20-02-07.
80. Welch AD (1983). "Folic acid: discovery and the exciting first decade". Perspectives in Biology and Medicine. 27 (1): 64–75. doi:10.1353/pbm.1983.0006. PMID 6359053. S2CID 31993927.
81. "Vitamins and minerals – names and facts". pubquizhelp.34sp.com. Archived from the original on 4 July 2007.
82. Vitamins: What Vitamins Do I Need?. Medical News Today. Retrieved on 30 November 2015.

Notes

1. Pekelharing CA (1905). "Over onze kennis van de waarde der voedingsmiddelen uit chemische fabrieken" [About our knowledge of the value of food products from chemical factories]. Nederlands Tijdschrift voor Geneeskunde (in Dutch). 41: 111–124.

External links

• USDA RDA chart in PDF format
• Health Canada Dietary Reference Intakes Reference Chart for Vitamins
• NIH Office of Dietary Supplements: Fact Sheets Archived 16 September 2008 at the Wayback Machine
• "Vitamins and minerals". nhs.uk. 23 October 2017.

• Vitamins
• Essential nutrients
• Nutrition