Retinol (one vitamer of Vitamin A)

A vitamin is an organic compound required as a nutrient in tiny amounts by an organism.^[1] A compound is called a vitamin when it cannot be synthesized in sufficient quantities by an organism, and must be obtained from the diet. Thus, the term is conditional both on the circumstances and the particular organism. For example, ascorbic acid functions as vitamin C for some animals but not others, and vitamins D and K are required in the human diet only in certain circumstances.^[2] Vitamins are defined by their biological activity, not their structure. Thus, each "vitamin" actually refers to a number of vitamer compounds, which form a set of distinct chemical compounds that show the biological activity of a particular vitamin. Such a set of chemicals are grouped under an alphabetized vitamin "generic descriptor" title, such as "vitamin A," which (for example) includes retinal, retinol, and many carotenoids. ^[3] Vitamers are often inter-convertible in the body. The term vitamin does not include other essential nutrients such as dietary minerals, essential fatty acids, or essential amino acids, nor does it encompass the large number of other nutrients that promote health but that are not essential for life. Image File history File links No higher resolution available. ... Image File history File links No higher resolution available. ... The structure of retinol, the most common dietary form of vitamin A Vitamin A is an essential human nutrient. ... A nutrient is a substance used in an organisms metabolism which must be taken in from the environment. ... Domains and Kingdoms Nanobes Acytota Cytota Bacteria Neomura Archaea Eukaryota Bikonta Apusozoa Rhizaria Excavata Archaeplastida Rhodophyta Glaucophyta Plantae Heterokontophyta Haptophyta Cryptophyta Alveolata Unikonta Amoebozoa Opisthokonta Choanozoa Fungi Animalia An ericoid mycorrhizal fungus Life on Earth redirects here. ... Biosynthesis is a phenomenon where chemical compounds are produced from simpler reagents. ... This article deals with the molecular aspects of ascorbic acid. ... This article is about the nutrient. ... Vitamin D is a fat soluble vitamin that contributes to the maintenance of normal levels of calcium and phosphorus in the bloodstream. ... Vitamin K1 (phylloquinone). ... Retinal, technically called retinene1 or retinaldehyde, is a light-sensitive retinene molecule found in the photoreceptor cells of the retina. ... Retinol, the animal form of vitamin A, is a yellow fat-soluble, antioxidant vitamin important in vision and bone growth. ... The orange ring surrounding Grand Prismatic Spring is due to carotenoid molecules, produced by huge mats of algae and bacteria. ... An essential nutrient is a nutrient required for normal body functioning that cannot be synthesized by the body. ... Dietary minerals are chemical elements required by living organisms. ... Essential fatty acids, or EFAs, are fatty acids that cannot be constructed within an organism from other components (generally all references are to humans) by any known chemical pathways; and therefore must be obtained from the diet. ... An essential amino acid or indispensable amino acid is an amino acid that cannot be synthesized de novo by the organism (usually referring to humans), and therefore must be supplied in the diet. ...

Vitamins have diverse biochemical functions, including function as hormones (e.g. vitamin D), antioxidants (e.g. vitamin E), and mediators of cell signaling and regulators of cell and tissue growth and differentiation (e.g. vitamin A) ^[4]. The largest number of vitamins (e.g. B complex vitamins) function as precursors for enzyme cofactor bio-molecules (coenzymes), that help act as catalysts and substrates in metabolism. When acting as part of a catalyst, vitamins are bound to enzymes and are called prosthetic groups. For example, biotin is part of enzymes involved in making fatty acids. Vitamins also act as coenzymes to carry chemical groups between enzymes. For example, folic acid carries various forms of carbon group – methyl, formyl and methylene - in the cell. Although these roles in assisting enzyme reactions are vitamins' best-known function, the other vitamin functions are equally important.^[5] Hormone is also the NATO reporting name for the Soviet/Russian Kamov Ka-25 military helicopter. ... An antioxidant is a chemical that prevents the oxidation of other chemicals. ... A cofactor is any substance that needs to be present in addition to an enzyme to catalyze a certain reaction. ... A representation of the 3D structure of myoglobin, showing coloured alpha helices. ... Coenzyme A Coenzymes are small organic non-protein molecules that carry chemical groups between enzymes. ... It has been suggested that this article or section be merged into Catalysis. ... For other uses, see Substrate. ... Structure of the coenzyme adenosine triphosphate, a central intermediate in energy metabolism. ... Ribbon diagram of the enzyme TIM, surrounded by the space-filling model of the protein. ... A prosthetic group is a non-protein (non-amino acid) component of a conjugated protein. ... Vitamin H redirects here. ... In chemistry, especially biochemistry, a fatty acid is a carboxylic acid often with a long unbranched aliphatic tail (chain), which is either saturated or unsaturated. ... Coenzymes are a small organic non-protein molecules that carry chemical groups between enzymes. ... Folic acid and folate (the anion form) are forms of the water-soluble Vitamin B9. ... In chemistry a methyl-group is a hydrophobic Alkyl functional group which is derived from methane (CH4). ... In organic chemistry, formyl is the radical or functional group with the formula -COH and structure - C = O | H The formyl group is the acyl of formic acid and the chief functional group of aldehydes. ... In chemistry, methylene is a divalent functional group CH2 derived formally from methane. ...

Until the 1800s, vitamins were obtained solely through food intake, and changes in diet (which, for example, could occur during a particular growing season) can alter the types and amounts of vitamins ingested. Vitamins have been produced as commodity chemicals and made widely available as inexpensive pills for several decades,^[6] allowing supplementation of the dietary intake.

Fruits and vegetables are often a good source of vitamins.

Image File history File links Download high resolution version (1280x960, 251 KB) Taken on July 5th in Barcelona photo by Dungodung File links The following pages link to this file: Market ... Image File history File links Download high resolution version (1280x960, 251 KB) Taken on July 5th in Barcelona photo by Dungodung File links The following pages link to this file: Market ...

History

The value of eating certain foods to maintain health was recognized long before vitamins were identified. The ancient Egyptians knew that feeding a patient liver would help cure night blindness, an illness now known to be caused by a vitamin A deficiency. The advancement of ocean voyage during the Renaissance resulted in prolonged periods without access to fresh fruits and vegetables, and made illnesses from vitamin deficiency common among ship's crew. For the bird, see Liver bird. ... Nyctalopia (literally night blindness) is a condition making it difficult or impossible to see in the dark. ... The structure of retinol, the most common dietary form of vitamin A Vitamin A is an essential human nutrient. ... This article is about the European Renaissance of the 14th-17th centuries. ...

In 1749, 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.^[7] 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 sailors of that organization. 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 by maintaining the morale of the crew while on board, rather than by a diet of fresh food.^[7] 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.^[7] Events While in debtors prison, John Cleland writes Fanny Hill (Memoirs of a Woman of Pleasure). ... This article is about the country. ... This article is about the medical specialty. ... James Lind (1716 in Edinburgh – 1794 in Gosport) was the pioneer of naval hygiene in the Royal Navy. ... For other uses, see Citrus (disambiguation). ... Scurvy (N.Lat. ... Tropocollagen triple helix. ... The gingiva (sing. ... 1753 was a common year starting on Monday (see link for calendar). ... Look up limey in Wiktionary, the free dictionary. ... This article is about the navy of the United Kingdom. ... The red line indicates the 10°C isotherm in July, commonly used to define the Arctic region border Artificially coloured topographical map of the Arctic region The Arctic is the region around the Earths North Pole, opposite the Antarctic region around the South Pole. ... Alternative meaning: Nineteenth Century (periodical) (18th century — 19th century — 20th century — more centuries) As a means of recording the passage of time, the 19th century was that century which lasted from 1801-1900 in the sense of the Gregorian calendar. ... Hygiene refers to practices associated with ensuring good health and cleanliness. ... This article or section does not cite any references or sources. ... (19th century - 20th century - 21st century - more centuries) Decades: 1900s 1910s 1920s 1930s 1940s 1950s 1960s 1970s 1980s 1990s As a means of recording the passage of time, the 20th century was that century which lasted from 1901–2000 in the sense of the Gregorian calendar (1900–1999 in the... Scott of the Antarctic redirects here. ... Greek ἀνταρκτικός, opposite the arctic) is a continent surrounding the Earths South Pole. ... For other uses, see Canning (disambiguation). ...

In 1881, Russian surgeon Nikolai Lunin studied the effects of scurvy while at the University of Tartu in present-day Estonia.^[8] 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".^[8] However, his conclusions were rejected by other researchers when they were unable to reproduce his results. One difference was that he had used table sugar (sucrose), while other researchers had used milk sugar (lactose) that still contained small amounts of vitamin B. Year 1881 (MDCCCLXXXI) was a common year starting on Saturday (link will display the full calendar) of the Gregorian calendar (or a common year starting on Thursday of the 12-day slower Julian calendar). ... This article is about the animal. ... A glass of cows milk. ... A representation of the 3D structure of myoglobin showing coloured alpha helices. ... For other uses, see FAT. Fats consist of a wide group of compounds that are generally soluble in organic solvents and largely insoluble in water. ... Lactose is a disaccharide found in milk. ... This article is about common table salt. ... Flash point N/A Except where noted otherwise, data are given for materials in their standard state (at 25 Â°C, 100 kPa) Infobox disclaimer and references Sucrose (common name: table sugar, also called saccharose) is a disaccharide (glucose + fructose) with the molecular formula C12H22O11. ... Lactose is a disaccharide that consists of β-D-galactose and β-D-glucose molecules bonded through a β1-4 glycosidic linkage. ... Vitamin B is a complex of several vitamins. ...

In the Orient where polished white rice was the common staple food of the middle class, beriberi resulting from lack of vitamin B was endemic. In 1884, Takaki Kanehiro, a British trained medical doctor of the Japanese Navy observed that beriberi was endemic among low ranking crew who often ate nothing but rice but not among crews of Western navies and officers who were entitled to a Western-style diet. Kanehiro initially believed that lack of protein was the chief cause of beriberi. With the support of 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 with beriberi and 25 deaths, while the latter group had only 14 cases of beriberi and no deaths. This convinced Kanehiro and the Japanese Navy that diet was the cause of beriberi. This was confirmed in 1897, when Christiaan Eijkman discovered that feeding unpolished rice instead of the polished variety to chickens helped to prevent beriberi in the chickens. The following year, Frederick Hopkins postulated that some foods contained "accessory factors"—in addition to proteins, carbohydrates, fats, et cetera—that were necessary for the functions of the human body.^[7] Hopkins was awarded the 1929 Nobel Prize for Physiology or Medicine with Christiaan Eijkman for their discovery of several vitamins. Beriberi is a nervous system ailment caused by thiamine (vitamin B1) deficiency. ... Takaki Kanehiro ); (30 October 1849–13 April 1920) was a Japanese naval physician. ... The Imperial Japanese Navy (IJN) (大日本帝國海軍 Dai-Nippon Teikoku Kaigun or 日本海軍 Nippon Kaigun) was the navy of Japan before 1945. ... For other uses, see Battleship (disambiguation). ... 1897 (MDCCCXCVII) was a common year starting on Friday (see link for calendar). ... Christiaan Eijkman (August 11, 1858—November 5, 1930) was a Dutch physician and pathologist whose demonstration that beriberi is caused by poor diet led to the discovery of vitamins. ... For other uses, see Rice (disambiguation). ... Sir Frederick Gowland Hopkins (June 20, 1861 – May 16, 1947) was an English biochemist, he was awarded the Nobel Prize in Physiology or Medicine in 1929 with Christiaan Eijkman for the discovery of vitamins. ... Year 1929 (MCMXXIX) was a common year starting on Tuesday (link will display the full calendar) of the Gregorian calendar. ... List of Nobel Prize laureates in Physiology or Medicine from 1901 to the present day. ...

In 1910, Japanese scientist Umetaro Suzuki succeeded in extracting a water-soluble complex of micronutrients from rice bran and named it aberic acid. He published this discovery in a Japanese scientific journal.^[9] 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. Polish biochemist Kazimierz Funk isolated the same complex of micronutrients and proposed the complex be named "Vitamine" (a portmanteau of "vital amine") in 1912.^[10] The name soon became synonymous with Hopkins' "accessory factors", and by the time it was shown that not all vitamins were amines, the word was already ubiquitous. In 1920, Jack Cecil Drummond proposed that the final "e" be dropped to deemphasize the "amine" reference after the discovery that vitamin C had no amine component. Suzuki Umetaro (鈴木梅太郎, April 7, 1874 – September 20, 1943) was a Japanese scientist. ... Thiamine mononitrate Thiamine or thiamin, also known as vitamin B1, is a colorless compound with chemical formula C12H17ClN4OS. It is soluble in water and insoluble in alcohol. ... Kazimierz Funk (February 23, 1884 - January 19, 1967), commonly anglicized as Casimir Funk, was a Polish biochemist, generally credited with the first formulation of the concept of Vitamins in 1912, which he called vital amines or vitamines. ... A portmanteau (IPA: ) is a word or morpheme that fuses two or more words or word parts to give a combined or loaded meaning. ... The general structure of an amine Amines are organic compounds and a type of functional group that contain nitrogen as the key atom. ... Year 1920 (MCMXX) was a leap year starting on Thursday (link will display 1920) of the Gregorian calendar. ... he was a weenie ... This article is about the nutrient. ...

Riboflavin (Vitamin B₂)

Throughout the early 1900s, the use of deprivation studies allowed scientists to isolate and identify a number of vitamins. Initially, lipid from fish oil was used to cure rickets in rats, and the fat-soluble nutrient was called "antirachitic A". The irony here is that the first "vitamin" bioactivity ever isolated, which cured rickets, was initially called "vitamin A", the bioactivity of which is now called vitamin D.^[11] What we now call "vitamin A" was identified in fish oil because it was inactivated by ultraviolet light. In 1931, Albert Szent-Györgyi and a fellow researcher Joseph Svirbely determined that "hexuronic acid" was actually vitamin C and noted its anti-scorbutic activity. In 1937, Szent-Györgyi was awarded the Nobel Prize for his discovery. In 1943 Edward Adelbert Doisy and Henrik Dam were awarded the Nobel Prize for their discovery of vitamin K and its chemical structure. Image File history File links No higher resolution available. ... Image File history File links No higher resolution available. ... Riboflavin (E101), also known as vitamin B2, is an easily absorbed micronutrient with a key role in maintaining health in animals. ... Vitamin B is a complex of several vitamins. ... Äž: For the film, see: 1900 (film). ... Fish Oil is oil derived from fishes. ... Rickets is a softening of the bones in children potentially leading to fractures and deformity. ... Species 50 species; see text *Several subfamilies of Muroids include animals called rats. ... Vitamin D is a fat soluble vitamin that contributes to the maintenance of normal levels of calcium and phosphorus in the bloodstream. ... For other uses, see Ultraviolet (disambiguation). ... Year 1931 (MCMXXXI) was a common year starting on Thursday (link will display full 1931 calendar) of the Gregorian calendar. ... Albert Szent-Györgyi at the time of his appointment to the National Institutes of Health Albert Szent-Györgyi de Nagyrápolt (September 16, 1893 – October 22, 1986) was a Hungarian physiologist who won the Nobel Prize in Physiology or Medicine in 1937. ... This article is about the nutrient. ... Scurvy (N.Lat. ... Emil Adolf von Behring was the first person to receive the Nobel Prize in Physiology or Medicine, for his work on the treatment of diphtheria. ... Year 1943 (MCMXLIII) was a common year starting on Friday (the link will display full 1943 calendar) of the Gregorian calendar. ... Dr. Edward Adelbert Doisy (November 3, 1893 - October 23, 1986) was an American biochemist, he was awarded the Nobel Prize in Physiology or Medicine in 1943 with Henrik Dam for their discovery of vitamin K and its chemical structure. ... Henrik Dam (Full name Carl Peter Henrik Dam) (February 21, 1895 – April 18, 1976) was a Danish biochemist and physiologist. ... Emil Adolf von Behring was the first person to receive the Nobel Prize in Physiology or Medicine, for his work on the treatment of diphtheria. ... Vitamin K1 (phylloquinone). ...

In humans

Vitamins are classified as either water-soluble, meaning that they dissolve easily in water, or fat-soluble vitamins, which are absorbed through the intestinal tract with the help of lipids (fats). In general, water-soluble vitamins are readily excreted from the body. Each vitamin is typically used in multiple reactions and, therefore, most have multiple functions.^[12] Impact from a water drop causes an upward rebound jet surrounded by circular capillary waves. ... For other uses, see FAT. Fats consist of a wide group of compounds that are generally soluble in organic solvents and largely insoluble in water. ... The gastrointestinal or digestive tract, also referred to as the GI tract or the alimentary canal or the gut, is the system of organs within multicellular animals which takes in food, digests it to extract energy and nutrients, and expels the remaining waste. ... Some common lipids. ...

In humans there are 13 vitamins: 4 fat-soluble (A, D, E and K) and 9 water-soluble (8 B vitamins and vitamin C).

Solubility is a chemical property referring to the ability for a given substance, the solute, to dissolve in a solvent. ... Reference Daily Intake (RDI) is the daily dietary intake level of a nutrient considered sufficient to meet the requirements of nearly all (97–98%) healthy individuals in each life-stage and gender group. ... The structure of retinol, the most common dietary form of vitamin A Vitamin A is an essential human nutrient. ... The Retinoids are a class of chemical compounds that are related chemically to vitamin A. Retinoids are used in medicine, primarily due to the way they regulate epithelial cell growth. ... Retinol, the animal form of vitamin A, is a yellow fat-soluble, antioxidant vitamin important in vision and bone growth. ... The Retinoids are a class of chemical compounds that are related chemically to vitamin A. Retinoids are used in medicine, primarily due to the way they regulate epithelial cell growth. ... The orange ring surrounding Grand Prismatic Spring is due to carotenoid molecules, produced by huge mats of algae and bacteria. ... Nyctalopia (literally night blindness) is a condition making it difficult or impossible to see in the dark. ... Keratomalacia is a eye disorder that leads to a dry cornea. ... The effects of excessive vitamin A intake include: birth defects liver abnormalities, reduced bone mineral density that may result in osteoporosis coarse bone growths hair loss excessive skin dryness/peeling Signs of acute toxicity include nausea and vomiting, headache, dizziness, blurred vision, and loss of muscular coordination. ... The B vitamins are eight water-soluble vitamins that play important roles in cell metabolism. ... For the similarly spelled nucleic acid, see Thymine Thiamine or thiamin, also known as vitamin B1, is one of the B vitamins. ... Beriberi is a nervous system ailment caused by thiamine (vitamin B1) deficiency. ... Riboflavin (E101), also known as vitamin B2, is an easily absorbed micronutrient with a key role in maintaining health in animals. ... Riboflavin (E101), also known as vitamin B2, is an easily absorbed micronutrient with a key role in maintaining health in animals. ... Riboflavin deficiency is seen in association with: protein and energy malnutrition alcoholism The clinical features include: dry mucus membranes, affecting: mouth eyes genitalia normochromic, normocytic anaemia Treatment with riboflavin, 6 mg per day. ... Niacin, also known as nicotinic acid or vitamin B3, is a water-soluble vitamin whose derivatives such as NADH, NAD, NAD+, and NADP play essential roles in energy metabolism in the living cell and DNA repair. ... Niacin, also known as nicotinic acid or vitamin B3, is a water-soluble vitamin whose derivatives such as NADH play essential roles in energy metabolism in the living cell. ... Pellagra is a vitamin deficiency disease caused by dietary lack of niacin (vitamin B3) and protein, especially proteins containing the essential amino acid tryptophan. ... Pantothenic acid, also called vitamin B5 (a B vitamin), is a water-soluble vitamin required to sustain life (essential nutrient). ... Paresthesia or paraesthesia (in British English) is a sensation of tingling, pricking, or numbness of a persons skin with no apparent long-term physical effect, more generally known as the feeling of pins and needles or of a limb being asleep (but not directly related to the phenomenon of... Main article: vitamin B6 Pyridoxine is one of the compounds that can be called vitamin B6, along with Pyridoxal and Pyridoxamine. ... The two major forms of vitamin B6 are pyridoxine and pyridoxamine. ... Pyridoxal is one of the three natural organic compounds, along with pyridoxamine and pyridoxine, that comprise vitamin B6. ... This article discusses the medical condition. ... // Proprioception (PRO-pree-o-SEP-shun (IPA pronunciation: ); from Latin proprius, meaning ones own and perception) is the sense of the relative position of neighbouring parts of the body. ... Vitamin H redirects here. ... Dermatitis is a blanket term literally meaning inflammation of the skin. It is usually used to refer to eczema, which is also known as Dermatitis eczema. ... Enteritis is the inflammation of the small intestine (inflammation of the large intestine is termed colitis). ... Folic acid and folate (the anion form) are forms of the water-soluble Vitamin B9. ... Folinic acid (INN) or leucovorin (USAN), generally administered as calcium folinate (or leucovorin calcium), is an adjuvant used in cancer chemotherapy involving the drug methotrexate. ... A congenital disorder is a medical condition or defect that is present at or before birth (for example, congenital heart disease). ... In the developing vertebrate nervous system, the neural tube is the precursor of the central nervous system, which comprises the brain and spinal cord. ... Cyanocobalamin is a compound that is metabolized to a vitamin in the B complex commonly known as vitamin B12 (or B12 for short). ... Hydroxocobalamin (OHCbl) is a natural analog of vitamin B12, a basic member of the cobalamin family of compounds. ... Chemical structure of Vitamin B12 The term vitamin B12 (or B12 for short) is used in two different ways. ... Megaloblastic anemia is anemia resulting from a deficiency of vitamin B12 and folic acid. ... This article is about the nutrient. ... This article deals with the molecular aspects of ascorbic acid. ... Scurvy (N.Lat. ... It has been suggested that Dynamic Flow be merged into this article or section. ... Vitamin D is a fat soluble vitamin that contributes to the maintenance of normal levels of calcium and phosphorus in the bloodstream. ... Ergocalciferol (Deltalin®, Eli Lilly and Company) is a form of Vitamin D, also called vitamin D2. ... Chemical structure of cholecalciferol Cholecalciferol is a form of Vitamin D, also called vitamin D3. ... Rickets is a softening of the bones in children potentially leading to fractures and deformity. ... Osteomalacia is a softening of the bones, resulting from defective bone mineralisation. ... Hypervitaminosis D is a state of Vitamin D toxicity. ... Tocopherol, or Vitamin E, is a fat-soluble vitamin in eight forms that is an important antioxidant. ... Tocopherol, or vitamin E, is a fat-soluble vitamin in eight forms that is an important antioxidant. ... Chemical structure of Tocotrienol Tocotrienols – Together with Tocopherols, compose the vitamin E family. ... Hemolytic anemia is anemia due to hemolysis, the abnormal breakdown of red blood cells either in the blood vessels (intravascular hemolysis) or elsewhere in the body (extravascular). ... Vitamin K1 (phylloquinone). ... Phylloquinone is a polycyclic aromatic ketone, based on 1,4-naphthoquinone, with 2-methyl and 3-phytyl functional groups. ... Vitamin K denotes a group of 2-methilo-naphthoquinone derivatives. ... In medicine (hematology), a bleeding diathesis is a propensity to bleeding (hemorrhage) due to a defect in the system of coagulation. ...

In nutrition and diseases

Vitamins are essential for the normal growth and development of a multicellular organism. Using the genetic blueprint inherited from its parents, a fetus begins to develop, at the moment of conception, 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.^[21] For other uses, see Fetus (disambiguation). ... For other uses, see Skin (disambiguation). ... This article is about the skeletal organs. ... For other uses of Muscles, see Muscles (disambiguation). ...

For the most part, vitamins are obtained with food, but a few are obtained by other means. For example, microorganisms in the intestine—commonly known as "gut flora"—produce vitamin K and biotin, while one form of vitamin D is synthesized in the skin with the help of natural ultraviolet in sunlight. Humans can produce some vitamins from precursors they consume. Examples include vitamin A, produced from beta carotene, and niacin, from the amino acid tryptophan.^[13] Escherichia coli, one of the many species of bacteria present in the human gut. ... For other uses, see Skin (disambiguation). ... For other uses, see Ultraviolet (disambiguation). ... Prism splitting light High Resolution Solar Spectrum Sunlight in the broad sense is the total spectrum of the electromagnetic radiation given off by the Sun. ... The structure of retinol, the most common dietary form of vitamin A Vitamin A is an essential human nutrient. ... Beta-carotene is a form of carotene with β-rings at both ends. ... This article is about the class of chemicals. ... Tryptophan (abbreviated as Trp or W)[1] is one of the 20 standard amino acids, which are the building blocks of proteins, and an essential amino acid in the human diet. ...

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 respiration.

Deficiencies

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.^[20] People who eat a varied diet are unlikely to develop a severe primary vitamin deficiency. In contrast, restrictive diets have the potential to cause prolonged vitamin deficits, which may result in often painful and potentially deadly diseases. This article is about the medical term. ...

Because human bodies do not store most vitamins, humans must consume them regularly to avoid deficiency. Human bodily stores for different vitamins vary widely; vitamins A, D, and B₁₂ are stored in significant amounts in the human body, mainly in the liver,^[20] and an adult human's diet may be deficient in vitamins A and B₁₂ for many months before developing a deficiency condition. Vitamin B₃ is not stored in the human body in significant amounts, so stores may only last a couple of weeks.^[14][20] For the bird, see Liver bird. ...

Well-known human vitamin deficiencies involve thiamine (beriberi), niacin (pellagra), vitamin C (scurvy) and vitamin D (rickets). In much of the developed world, such deficiencies are rare; this is due to (1) an adequate supply of food; and (2) the addition of vitamins and minerals to common foods, often called fortification.^[13][20] Beriberi is a nervous system ailment caused by thiamine (vitamin B1) deficiency. ... Pellagra is a vitamin deficiency disease caused by dietary lack of niacin (vitamin B3) and protein, especially proteins containing the essential amino acid tryptophan. ... Scurvy (N.Lat. ... Rickets is a softening of the bones in children potentially leading to fractures and deformity. ...

Recent lines of evidence also suggest a link between nutrition and mental disorders, as evidenced by Lakhan & Vieira (2008)^[22].

Side effects and overdose

In large doses, some vitamins have documented side effects that tend to be more severe with a larger dosage. The likelihood of consuming too much of any vitamin from food is remote, but overdosing from vitamin supplementation does occur. At high enough dosages some vitamins cause side effects such as nausea, diarrhea, and vomiting.^[23][14] When side effects emerge, recovery is often accomplished by reducing the dosage. The concentrations of vitamins an individual can tolerate vary widely, and appear to be related to age and state of health.^[24] In the United States, overdose exposure to all formulations of vitamins was reported by 62,562 individuals in 2004 (nearly 80% of these exposures were in children under the age of 6), leading to 53 "major" life-threatening outcomes and 3 deaths^[25]—a small number in comparison to the 19,250 people who died of unintentional poisoning of all kinds in the U.S. in the same year (2004).^[26] For other uses, see Nausea (disambiguation). ... Diarrhea, also spelled diarrhoea (see spelling differences), is a condition in which the sufferer has frequent watery, loose bowel movements (from the Greek word διάρροια; literally meaning through-flowing). Acute infectious diarrhea is a common cause of death in developing countries (particularly among infants), accounting for 5 to 8 million deaths... Vomiting (or emesis) is the forceful expulsion of the contents of ones stomach through the mouth. ...

Supplements

Dietary supplements, often containing vitamins, are used to ensure that adequate amounts of nutrients are obtained on a daily basis, if optimal amounts of the nutrients cannot be obtained through a varied diet. Scientific evidence supporting the benefits of some dietary supplements is well established for certain health conditions, but others need further study.^[27] A dietary supplement is intended to supply nutrients, (vitamins, minerals, fatty acids or amino acids) that are missing or not consumed in sufficient quantity in a persons diet. ...

In the United States, advertising for dietary supplements is required to include a disclaimer that the product is not intended to treat, diagnose, mitigate, prevent, or cure disease, and that any health claims have not been evaluated by the Food and Drug Administration.^[27] In some cases, dietary 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.^[27] Vitamin supplements may also contain levels of vitamins many times higher, and in different forms, than one may ingest through food.^[28] Health claims on food labels are claims by manufacturers of food products that their food will reduce the risk of developing a disease or condition. ... ... “FDA” redirects here. ...

Intake of excessive quantities can cause vitamin poisoning, often due to overdose of Vitamin A and Vitamin D (The most common poisoning with multinutrient supplement pills does not involve a vitamin, but is rather due to the mineral iron). Due to toxicity, most common vitamins have recommended upper daily intake amounts. Vitamin poisoning, or hypervitaminosis, refers to a condition of high storage levels of vitamins, which can lead to toxic symptoms. ... The structure of retinol, the most common dietary form of vitamin A Vitamin A is an essential human nutrient. ... Vitamin D is a fat soluble vitamin that contributes to the maintenance of normal levels of calcium and phosphorus in the bloodstream. ... General Name, symbol, number iron, Fe, 26 Chemical series transition metals Group, period, block 8, 4, d Appearance lustrous metallic with a grayish tinge Standard atomic weight 55. ...

Governmental regulation of vitamin supplements

Most countries place dietary supplements in a special category under the general umbrella of foods, not drugs. This necessitates that the manufacturer, and not the government, be responsible for ensuring that its dietary supplement products are safe before they are marketed. Unlike drug products, that must explicitly be proven safe and effective for their intended use before marketing, there are often no provisions to "approve" dietary supplements for safety or effectiveness before they reach the consumer. Also unlike drug products, manufacturers and distributors of dietary supplements are not generally required to report any claims of injuries or illnesses that may be related to the use of their products.^{[29] [30]}

Names in current and previous nomenclatures

The reason the set of vitamins seems to skip 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 German-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 Koagulation of blood following wounding. At the time, most (but not all) of the letters from F through J were already designated, so the use of the letter K was considered quite reasonable.

The following table 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 B vitamins are eight water-soluble vitamins that play important roles in cell metabolism. ... For the programming language Adenine, see Adenine (programming language). ... The B vitamins are eight water-soluble vitamins that play important roles in cell metabolism. ... Adenosine monophosphate, also known as 5-adenylic acid and abbreviated AMP, is a nucleotide that is found in RNA. It is an ester of phosphoric acid with the nucleoside adenosine. ... Essential fatty acids are fatty acids that are required in the human diet. ... Essential fatty acids, or EFAs, are fatty acids that cannot be constructed within an organism from other components (generally all references are to humans) by any known chemical pathways; and therefore must be obtained from the diet. ... Riboflavin (E101), also known as vitamin B2, is an easily absorbed, water-soluble micronutrient with a key role in maintaining human health. ... Riboflavin (E101), also known as vitamin B2, is an easily absorbed micronutrient with a key role in maintaining health in animals. ... The B vitamins are eight water-soluble vitamins that play important roles in cell metabolism. ... Biotin, also known as vitamin H or B7 and C10H16N2O3S (Biotin; Coenzyme R, Biopeiderm), is a B-complex vitamin which is important in the catalysis of essential metabolic reactions to synthesize fatty acids, in gluconeogenesis, and to metabolize leucine. ... Vitamin H redirects here. ... The B vitamins are eight water-soluble vitamins that play important roles in cell metabolism. ... Choline // Choline is a nutrient, essential for cardiovascular and brain function, and for cellular membrane composition and repair. ... Catechol, also benzene-1,2-diol, is a phenol, with formula C6H4(OH)2. ... Riboflavin Flavin is a vaginal ring whose biochemical smell is pungent. ... Anthranilic acid has the formula C7H7NO2[1] and is an odorless white to yellow crystalline acid, which is freely soluble in water. ... Folic acid (the anion form is called folate) is a B-complex vitamin (once called vitamin M) that is important in preventing neural tube defects (NTDs) in the developing human fetus. ... Folic acid and folate (the anion form) are forms of the water-soluble Vitamin B9. ... The B vitamins are eight water-soluble vitamins that play important roles in cell metabolism. ... This article or section contains information that has not been verified and thus might not be reliable. ... Niacin, also known as nicotinic acid or vitamin B3, is a water-soluble vitamin whose derivatives such as NADH play essential roles in energy metabolism in the living cell. ... Flavonoids are a group of chemical compounds naturally found in certain fruits, vegetables, teas, wines, nuts, seeds, and roots. ... Nicotinic acid redirects here. ... Niacin, also known as nicotinic acid or vitamin B3, is a water-soluble vitamin whose derivatives such as NADH, NAD, NAD+, and NADP play essential roles in energy metabolism in the living cell and DNA repair. ... The B vitamins are eight water-soluble vitamins that play important roles in cell metabolism. ... Vitamin U is not a vitamin. ... S-Methylmethionine, or S-methyl-L-methionine, is a derivative of methionine with chemical formula C6H15NO2S. In plants, it is produced from methionine by the enzyme methionine S-methyltransferase. ...

See also

Food Portal

Image File history File links Portal. ... The Nutrition Facts table indicates the amounts of nutrients which experts recommend you limit or consume in adequate amounts. ... mccall is cooool Dietary minerals are the chemical elements required by living organisms, other than the four elements carbon, hydrogen, nitrogen, and oxygen which are present in common organic molecules. ... An essential amino acid or indispensable amino acid is an amino acid that cannot be synthesized de novo by the organism (usually referring to humans), and therefore must be supplied in the diet. ... An essential nutrient is a nutrient required for normal body functioning that cannot be synthesized by the body. ... Nootropics are so-called smart drugs. ... A nutrient is a substance used in an organisms metabolism which must be taken in from the environment. ... Space-filling model of the antioxidant metabolite glutathione. ... A dietary supplement is intended to supply nutrients, (vitamins, minerals, fatty acids or amino acids) that are missing or not consumed in sufficient quantity in a persons diet. ... Dietitians are experts in food and nutrition. ... It has been suggested that this article or section be merged with Vitamin. ... The term health freedom movement is used to describe the loose coalition of consumers and alternative medicine providers around the world who are pushing for unhindered freedom of choice in healthcare. ... To meet Wikipedias quality standards, this article or section may require cleanup. ... In nutrition and CAM, megavitamin therapy makes use of large amounts of vitamins, often many times greater than the recommended dietary allowance (RDA), to treat many types of diseases. ... Orthomolecular medicine and optimum nutrition are controversial medical and health approaches[1] that posit that many diseases and abnormalities result from various chemical imbalances or deficiencies and can be prevented, treated, or sometimes cured by achieving optimal levels of naturally occurring chemical substances, such as vitamins, dietary minerals, enzymes, antioxidants... Pharmacology (in Greek: pharmakon (φάρμακον) meaning drug, and lego (λέγω) to tell (about)) is the study of how drugs interact with living organisms to produce a change in function. ... Vitamin poisoning, or hypervitaminosis, refers to a condition of high storage levels of vitamins, which can lead to toxic symptoms. ... Whole food supplements comprise a unique class within the food supplement industry. ...

References

External links

• USDA RDA chart in PDF format
• Health Canada Dietary Reference Intakes Reference Chart for Vitamins
• NIH Office of Dietary Supplements: Fact Sheets
• NIH Office of Dietary Supplements. Dietary Supplements: Background Information