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A vitamin is an
organic molecule , CH4; is among the simplest organic compounds. In chemistry, organic compounds are generally any chemical compounds that contain carbon-hydrogen chemical bond, bonds. Due to carbon's ability to Catenation, catenate (form chains with other carbon ...
(or a set of molecules closely related chemically, i.e.
vitamer Vitamins A vitamin is an organic molecule (or a set of molecules closely related chemically, i.e. vitamers) that is an essential micronutrient which an organism In biology, an organism (from Ancient Greek, Greek: ὀργανισμ ...
s) that is an essential micronutrient which an
organism In biology, an organism () is any organic, life, living system that functions as an individual entity. All organisms are composed of cells (cell theory). Organisms are classified by taxonomy (biology), taxonomy into groups such as Multice ...

organism
needs in small quantities for the proper functioning of its
metabolism Metabolism (, from el, μεταβολή ''metabolē'', "change") is the set of life-sustaining chemical reactions in organisms. The three main purposes of metabolism are: the conversion of the energy in food to energy available to run cellu ...

metabolism
. Essential nutrients cannot be
synthesized Synthesis or synthesize may also refer to: Science Chemistry and biochemistry *Chemical synthesis, the execution of chemical reactions to form a more complex molecule from chemical precursors **Organic synthesis, the chemical synthesis of or ...

synthesized
in the organism, either at all or not in sufficient quantities, and therefore must be obtained through the
diet Diet may refer to: Food * Diet (nutrition), the sum of the food consumed by an organism or group * Dieting, the deliberate selection of food to control body weight or nutrient intake ** Diet food, foods that aid in creating a diet for weight loss ...
.
Vitamin C Vitamin C (also known as ascorbic acid and ascorbate) is a vitamin A vitamin is an organic molecule (or a set of molecules closely related chemically, i.e. vitamers) that is an Nutrient#Essential nutrients, essential micronutrient which ...

Vitamin C
can be synthesized by some species but not by others; it is not a vitamin in the first instance but is in the second. The term ''vitamin'' does not include the three other groups of
essential nutrient A nutrient is a substance Substance may refer to: * Substance (Jainism), a term in Jain ontology to denote the base or owner of attributes * Chemical substance, a material with a definite chemical composition * Matter, anything that has mass and ta ...
s:
minerals In geology and mineralogy, a mineral or mineral species is, broadly speaking, a solid chemical compound with a fairly well-defined chemical composition and a specific crystal structure that occurs naturally in pure form.John P. Rafferty, ed. (20 ...
,
essential fatty acid Essential fatty acids, or EFAs, are fatty acids that humans and other animals must ingest because the body requires them for good health but cannot Biosynthesis, synthesize them. The term "essential fatty acid" refers to fatty acids required for ...
s, and
essential amino acid An essential amino acid, or indispensable amino acid, is an amino acid Amino acids are organic compounds that contain amino (–NH2) and Carboxylic acid, carboxyl (–COOH) functional groups, along with a Substituent, side chain (R group) spe ...
s. Most vitamins are not single molecules, but groups of related molecules called
vitamer Vitamins A vitamin is an organic molecule (or a set of molecules closely related chemically, i.e. vitamers) that is an essential micronutrient which an organism In biology, an organism (from Ancient Greek, Greek: ὀργανισμ ...
s. For example, there are eight vitamers of
vitamin E Vitamin E is a group of eight fat soluble compounds that include four tocopherols and four tocotrienols. Vitamin E deficiency, which is rare and usually due to an underlying problem with digesting dietary fat rather than from a diet low in vi ...

vitamin E
: four
tocopherolTocopherols (; TCP) are a class of organic chemical compounds (more precisely, various methylated phenol Phenol (also called carbolic acid) is an aromatic organic compound , CH4; is among the simplest organic compounds. In chemistry, organic ...
s and four
tocotrienol The vitamin E family comprise four tocotrienols (alpha, beta, gamma, delta) and four tocopherols (alpha, beta, gamma, delta). The critical chemical structural difference between tocotrienols and tocopherols is that tocotrienols have unsaturated i ...
s. Some sources list fourteen vitamins, by including
choline Choline is an essential nutrient A nutrient is a substance Substance may refer to: * Substance (Jainism), a term in Jain ontology to denote the base or owner of attributes * Chemical substance, a material with a definite chemical composition * ...

choline
, but major health organizations list thirteen:
vitamin A Vitamin A is a group of unsaturated nutritional organic compounds , CH4; is among the simplest organic compounds. In chemistry, organic compounds are generally any chemical compounds that contain carbon-hydrogen chemical bond, bonds. Due to ...

vitamin A
(as all-''trans''-
retinol Retinol, also called vitamin A1, is a vitamin in the vitamin A family found in food and used as a dietary supplement. As a supplement it is used to treat and prevent vitamin A deficiency, especially that which results in xerophthalmia. In regi ...

retinol
, all-''trans''-retinyl-esters, as well as all-''trans''- beta-carotene and other
provitaminA provitamin is a substance that may be converted within the body to a vitamin A vitamin is an organic molecule (or a set of molecules closely related chemically, i.e. vitamers) that is an Nutrient#Essential nutrients, essential micronutrient w ...
A carotenoids), vitamin B1 (
thiamine Thiamine, also known as thiamin or vitamin B1, is a vitamin A vitamin is an organic molecule , CH4; is among the simplest organic compounds. In chemistry, organic compounds are generally any chemical compounds that contain carbon-hydrogen ...

thiamine
), vitamin B2 (
riboflavin Riboflavin, also known as vitamin B2, is a vitamin found in food and used as a dietary supplement. It is required by the body for cellular respiration. Food sources include egg (food), eggs, green vegetables, milk and other dairy products, meat, ...

riboflavin
), vitamin B3 (
niacin Niacin, also known as nicotinic acid, is an organic compound , CH4; is among the simplest organic compounds. In chemistry, organic compounds are generally any chemical compounds that contain carbon-hydrogen chemical bond, bonds. Due to carb ...

niacin
), vitamin B5 (
pantothenic acid Pantothenic acid, also called vitamin B5 is a water-soluble B vitamin and therefore an essential nutrient. All animals require pantothenic acid in order to synthesize coenzyme A (CoA) – essential for fatty acid metabolism – as well as to ...

pantothenic acid
), vitamin B6 (
pyridoxine Pyridoxine, also known as vitamin B6, is a form of vitamin B6 found commonly in food and used as dietary supplement. As a supplement it is used to treat and prevent pyridoxine deficiency, sideroblastic anaemia, pyridoxine-dependent epilepsy, ...

pyridoxine
), vitamin B7 (
biotin Biotin, also called vitamin B7, is one of the B vitamins B vitamins are a class of water-soluble vitamin A vitamin is an organic molecule (or a set of molecules closely related chemically, i.e. vitamers) that is an Nutrient#Essential nutrien ...

biotin
), vitamin B9 (
folic acid Folate, also known as vitamin B9 and folacin, is one of the B vitamins. Manufactured folic acid, which is converted into folate by the body, is used as a dietary supplement and in food fortification as it is more stable during processing and s ...

folic acid
or
folate Folate, also known as vitamin B9 and folacin, is one of the B vitamins. Manufactured folic acid, which is converted into folate by the body, is used as a dietary supplement A dietary supplement is a manufactured product intended to ...
), vitamin B12 (
cobalamin Vitamin B12, also known as cobalamin, is a water-soluble vitamin involved in the metabolism of every cell (biology), cell of the human body. It is one of eight B vitamins. It is a cofactor (biochemistry), cofactor in DNA synthesis, and in both ...

cobalamin
s), vitamin C (
ascorbic acid Vitamin C (also known as ascorbic acid and ascorbate) is a vitamin A vitamin is an organic molecule (or a set of molecules closely related chemically, i.e. vitamers) that is an Nutrient#Essential nutrients, essential micronutrient which ...

ascorbic acid
),
vitamin D Vitamin D is a group of Lipophilicity, fat-soluble secosteroids responsible for increasing intestinal absorption of calcium, magnesium, and phosphate, and many other biological effects. In humans, the most important compounds in this group ar ...
( calciferols),
vitamin E Vitamin E is a group of eight fat soluble compounds that include four tocopherols and four tocotrienols. Vitamin E deficiency, which is rare and usually due to an underlying problem with digesting dietary fat rather than from a diet low in vi ...

vitamin E
(
tocopherolTocopherols (; TCP) are a class of organic chemical compounds (more precisely, various methylated phenol Phenol (also called carbolic acid) is an aromatic organic compound , CH4; is among the simplest organic compounds. In chemistry, organic ...
s and
tocotrienol The vitamin E family comprise four tocotrienols (alpha, beta, gamma, delta) and four tocopherols (alpha, beta, gamma, delta). The critical chemical structural difference between tocotrienols and tocopherols is that tocotrienols have unsaturated i ...
s), and
vitamin K Vitamin K refers to structurally similar, fat-soluble vitamers found in foods and marketed as dietary supplements. The human body requires vitamin K for post-translational modification, post-synthesis modification of certain proteins that are r ...
(
phylloquinone Phytomenadione, also known as vitamin K1 or phylloquinone, is a vitamin A vitamin is an organic molecule (or a set of molecules closely related chemically, i.e. vitamers) that is an Nutrient#Essential nutrients, essential micronutrient which ...

phylloquinone
and
menaquinone Vitamin K2 or menaquinone () is one of three types of vitamin K, the other two being vitamin K1 (phylloquinone Phytomenadione, also known as vitamin K1 or phylloquinone, is a vitamin A vitamin is an organic molecule (or a set of molecules ...

menaquinone
s). 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 B vitamins are a class of water-soluble vitamins that play important roles in Cell (biology), cell metabolism and synthesis of red blood cells. Though these vitamins share similar names (B1, B2, B3, etc.), they are chemically distinct compounds that ...
vitamins function as enzyme cofactors (coenzymes) or the precursors for them. Vitamins C and E function as
antioxidant Antioxidants are Chemical compound, compounds that inhibit oxidation (mild reducing agent) are added to powdered potassium permanganate Potassium permanganate is an inorganic compound with the chemical formula KMnO4 and composed of potass ...

antioxidant
s. 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. Before 1935, the only source of vitamins was from food. If intake of vitamins was lacking, the result was vitamin deficiency and consequent deficiency diseases. Then, 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
multivitamin A multivitamin is a preparation intended to serve as a dietary supplement A dietary supplement is a manufactured product intended to supplement one's diet by taking a pill, capsule, tablet, powder or liquid. A supplement can provide nut ...
s, to prevent vitamin deficiencies in the general population. Governments have mandated the addition of some vitamins to
staple food 215px, Unprocessed seeds of spelt, a historically important staple food A staple food, food staple, or simply a staple, is a food Food is any substance consumed to provide Nutrient, nutritional support for an organism. Food is usually of pla ...

staple food
s such as flour or milk, referred to as
food fortification Food fortification or enrichment is the process of adding micronutrientMicronutrients are nutrient, essential elements required by organisms in varying quantities throughout life to orchestrate a range of physiological functions to maintain health. ...
, to prevent deficiencies. Recommendations for
folic acid Folate, also known as vitamin B9 and folacin, is one of the B vitamins. Manufactured folic acid, which is converted into folate by the body, is used as a dietary supplement and in food fortification as it is more stable during processing and s ...

folic acid
supplementation during
pregnancy Pregnancy, also known as gestation, is the time during which one or more offspring develops inside a woman. A multiple birth, multiple pregnancy involves more than one offspring, such as with twins. Pregnancy usually occurs by sexual intercour ...
reduced risk of infant neural tube defects. The term ''vitamin'' is derived from the word ''vitamine'', which was coined in 1912 by Polish biochemist Casimir Funk, who isolated a complex of micronutrients essential to life, all of which he presumed to be amines. 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." When this presumption was later determined not to be true, the "e" was dropped from the name. All vitamins were discovered (identified) between 1913 and 1948.


List


Classification

Vitamins are classified as either Hydrophilicity, water-soluble or lipophilicity, 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 intestinal 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 Biotin, also called vitamin B7, is one of the B vitamins B vitamins are a class of water-soluble vitamin A vitamin is an organic molecule (or a set of molecules closely related chemically, i.e. vitamers) that is an Nutrient#Essential nutrien ...

biotin
; it is deactivated by cooking. Pyrithiamine, a synthetic compound, has a molecular structure similar to thiamine, vitamin B1, 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.Kutsky, R.J. (1973). Handbook of Vitamins and Hormones. New York: Van Nostrand Reinhold,


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 prenatal development, 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 Vitamin A is a group of unsaturated nutritional organic compounds , CH4; is among the simplest organic compounds. In chemistry, organic compounds are generally any chemical compounds that contain carbon-hydrogen chemical bond, bonds. Due to ...

vitamin A
is synthesized from beta carotene; and
niacin Niacin, also known as nicotinic acid, is an organic compound , CH4; is among the simplest organic compounds. In chemistry, organic compounds are generally any chemical compounds that contain carbon-hydrogen chemical bond, bonds. Due to carb ...

niacin
is synthesized from the amino acid tryptophan. Vitamin C can be synthesized by some species but not by others. Vitamin B12, 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 human body, 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 Food fortification, 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.Dietary Reference Intakes (DRIs)
Food and Nutrition Board, Institute of Medicine, National Academies
Dietary Reference Intakes for Japanese (2010)
National Institute of Health and Nutrition, Japan
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.Dietary Reference Intakes: The Essential Guide to Nutrient Requirements, published by the Institute of Medicine's Food and Nutrition Board, currently available online at 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 cardiovascular disease, 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 tobacco smoking, 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.Use and Safety of Dietary Supplements
NIH office of Dietary Supplements.
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, pharmacopoeia, 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 language, 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 B vitamins were reclassified or determined not to be vitamins. For example, B9 is
folic acid Folate, also known as vitamin B9 and folacin, is one of the B vitamins. Manufactured folic acid, which is converted into folate by the body, is used as a dietary supplement and in food fortification as it is more stable during processing and s ...

folic acid
and five of the folates are in the range B11 through B16. Others, such as 4-Aminobenzoic acid, 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 nine lettered B complex vitamins (e.g., Bm). 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 any vitamins Q, R, T, V, W, X, Y or Z, nor are there substances officially designated as vitamins N or I, although the latter may have been another form of one of the other vitamins or a known and named nutrient of another type.


History

The value of eating certain foods to maintain health was recognized long before vitamins were identified. The ancient Egyptians knew that feeding liver (food), liver to a person may help with night blindness, an illness now known to be caused by a
vitamin A Vitamin A is a group of unsaturated nutritional organic compounds , CH4; is among the simplest organic compounds. In chemistry, organic compounds are generally any chemical compounds that contain carbon-hydrogen chemical bond, bonds. Due to ...

vitamin A
deficiency. The advancement 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 Scotland, Scottish surgeon James Lind (physician), 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 gingiva, gums, severe pain, and death.Jack Challem (1997
"The Past, Present and Future of Vitamins"
In 1753, Lind published his ''Treatise on the Scurvy'', which recommended using lemons and Lime (fruit), limes to avoid scurvy, which was adopted by the British Royal Navy. This led to the nickname ''limey'' for British sailors. Lind's discovery, however, was not widely accepted by individuals in the Royal Navy's Arctic expeditions in the 19th century, where it was widely believed that scurvy could be prevented by practicing good hygiene, regular exercise, and maintaining the morale of the crew while on board, rather than by a diet of fresh food. 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 at the time was that scurvy was caused by "tainted" canning, canned food. During the late 18th and early 19th centuries, the use of deprivation studies allowed scientists to isolate and identify a number of vitamins. Lipid from fish oil was used to cure rickets in rats, and the fat-soluble nutrient was called "antirachitic A". Thus, the first "vitamin" bioactivity ever isolated, which cured rickets, was initially called "vitamin A"; however, the bioactivity of this compound is now called
vitamin D Vitamin D is a group of Lipophilicity, fat-soluble secosteroids responsible for increasing intestinal absorption of calcium, magnesium, and phosphate, and many other biological effects. In humans, the most important compounds in this group ar ...
. In 1881, Russian Empire, Russian medical doctor 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 salt (chemistry), 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 Cornelius Pekelharing appeared in a Dutch medical journal 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 (epidemiology), 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. Hopkins and Eijkman were awarded the Nobel Prize for Physiology or Medicine in 1929 for their discoveries.


"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. Maximilian Nierenstein, 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 Vitamin A is a group of unsaturated nutritional organic compounds , CH4; is among the simplest organic compounds. In chemistry, organic compounds are generally any chemical compounds that contain carbon-hydrogen chemical bond, bonds. Due to ...

vitamin A
) have an amine component.


Nobel Prizes for vitamin research

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 Vitamin C (also known as ascorbic acid and ascorbate) is a vitamin A vitamin is an organic molecule (or a set of molecules closely related chemically, i.e. vitamers) that is an Nutrient#Essential nutrients, essential micronutrient which ...

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 anti-scurvy, scorbutic activity 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 Vitamin K refers to structurally similar, fat-soluble vitamers found in foods and marketed as dietary supplements. The human body requires vitamin K for post-translational modification, post-synthesis modification of certain proteins that are r ...
and its chemical structure. In 1967, George Wald was awarded the Nobel Prize (along with Ragnar Granit and Haldan Keffer Hartline) for his discovery that vitamin A could participate directly in a physiological process. 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, Ragnar Granit, Haldan Keffer Hartline and George Wald were awarded the Nobel Prize in Physiology and Medicine "..."for their discoveries concerning the primary physiological and chemical visual processes in the eye." Photoreceptor cells in the eye contain a chromophore composed of the protein opsin and 11-cis retinal. When struck by light, 11-cis retinal undergoes photoisomerization to all-trans retinal and via signal transduction cascade send a nerve signal to the brain. The all-trans retinal is reduced to all-trans retinol and travels back to the retinal pigment epithelium to be recycled to 11-cis retinal and conjugated to opsin.


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. World War II researchers focused on the need to ensure adequate nutrition, especially in 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 has led to an obsessive consumption of additives, the beneficial effects of which are questionable.


Etymology

The term ''vitamin'' was derived from "vitamine", a compound (linguistics), compound word coined in 1912 by the Polish biochemist Casimir Funk when working at the Lister Institute of Preventive Medicine. The name is from ''vital'' and ''amine'', meaning amine of life, because it was suggested in 1912 that the organic micronutrient food factors that prevent beriberi and perhaps other similar dietary-deficiency diseases might be chemical amines. This was true of
thiamine Thiamine, also known as thiamin or vitamin B1, is a vitamin A vitamin is an organic molecule , CH4; is among the simplest organic compounds. In chemistry, organic compounds are generally any chemical compounds that contain carbon-hydrogen ...

thiamine
, but after it was found that other such micronutrients were not amines the word was shortened to vitamin in English.


See also

*Vitamin deficiency *Hypervitaminosis *Human nutrition *Phytochemical


References


External links


USDA RDA chart in PDF format
*[http://dietary-supplements.info.nih.gov/Health_Information/Vitamin_and_Mineral_Supplement_Fact_Sheets.aspx NIH Office of Dietary Supplements: Fact Sheets] {{Authority control Vitamins, Essential nutrients Nutrition