Cholecalciferol (D₃)

Ergocalciferol (D₂). Cholecalciferol is a form of Vitamin D, also called vitamin D3. Ergocalciferol (Deltalin Eli Lilly and Company) is a form of Vitamin D, also called vitamin D2. Note double bond at top center.

Vitamin D is a group of fat-soluble prohormones, the two major forms of which are vitamin D₂ (or ergocalciferol) and vitamin D₃ (or cholecalciferol). A prohormone is a substance that is a precursor to a Hormone, usually having minimal hormonal effect by itself Ergocalciferol (Deltalin Eli Lilly and Company) is a form of Vitamin D, also called vitamin D2. Cholecalciferol is a form of Vitamin D, also called vitamin D3. ^[1] The term vitamin D also refers to metabolites and other analogues of these substances. Metabolomics is the "systematic study of the unique chemical fingerprints that specific cellular processes leave behind" - specifically the study of their small-molecule metabolite Vitamin D₃ is produced in skin exposed to sunlight, specifically ultraviolet B radiation. Ultraviolet ( UV) light is Electromagnetic radiation with a Wavelength shorter than that of Visible light, but longer than X-rays

Vitamin D plays an important role in the maintenance of organ systems. In Biology, an organ ( Latin: organum, "instrument tool" from Greek όργανον - organon "organ instrument ^[2]

• Vitamin D regulates the calcium and phosphorus levels in the blood by promoting their absorption from food in the intestines, and by promoting re-absorption of calcium in the kidneys. Calcium (ˈkælsiəm is the Chemical element with the symbol Ca and Atomic number 20 Phosphorus, (ˈfɒsfərəs is the Chemical element that has the symbol P and Atomic number 15 Blood is a specialized Bodily fluid that delivers necessary substances to the body's cells ��such as nutrients and oxygen—and transports Waste products In Anatomy, the intestine is the segment of the alimentary canal extending from the Stomach to the Anus and in humans and other mammals consists The kidneys are complicated organs that have numerous biological roles
• It promotes bone formation and mineralization and is essential in the development of an intact and strong skeleton. Bones are rigid organs that form part of the Endoskeleton of Vertebrates They function to move support and protect the various organs of the body produce For other uses see Mineralization In biology mineralization refers to the process where a substance is converted from an organic substance to an In Biology, the skeleton is a strong and often a rigid framework that supports the body of an animal holding it upright and giving it shape and strength (Also skeletal However, at very high levels it will promote the resorption of bone. Bone resorption is the process by which Osteoclasts break down Bone and release the Minerals resulting in a transfer of calcium from bone fluid to the blood
• It inhibits parathyroid hormone secretion from the parathyroid gland. Parathyroid hormone (PTH, or parathormone, is secreted by the Parathyroid glands as a Polypeptide containing 84 Amino acids. The parathyroid glands are small endocrine Glands in the neck usually located behind the Thyroid gland, which produce Parathyroid hormone.
• Vitamin D affects the immune system by promoting phagocytosis, anti-tumor activity, and immunomodulatory functions. An immune system is a collection of mechanisms within an Organism that protects against Disease by identifying and killing Pathogens and Tumor Phagocytosis is the cellular process of engulfing solid particles by the Cell membrane to form an internal Phagosome, or "food vacuole

Vitamin D deficiency can result from inadequate intake coupled with inadequate sunlight exposure, disorders that limit its absorption, conditions that impair conversion of vitamin D into active metabolites, such as liver or kidney disorders, or, rarely, by a number of hereditary disorders. Metabolomics is the "systematic study of the unique chemical fingerprints that specific cellular processes leave behind" - specifically the study of their small-molecule metabolite The liver is a vital organ in the human body and is present in Vertebrates and some other animals ^[2] Deficiency results in impaired bone mineralization, and leads to bone softening diseases, rickets in children and osteomalacia in adults, and possibly contributes to osteoporosis. Rickets is a softening of the bones in children potentially leading to fractures and deformity Osteomalacia is the general term for the softening of the bones due to defective Bone mineralization. Osteoporosis is a Disease of Bone that leads to an increased risk of fracture. Research has indicated that vitamin D deficiency is linked to colon cancer and more, recently, to breast cancer^[3]. Conflicting evidence links vitamin D deficiency to other forms of cancer. Low levels of vitamin D appear to be associated with higher risk of heart attack in men, according to a report in the June 9, 2008 issue of Archives of Internal Medicine. Events 53 - Roman Emperor Nero marries Claudia Octavia 62 - Claudia Octavia commits ^[4]

Forms

Several forms (vitamers) of vitamin D have been discovered. The vitamers of a particular Vitamin are all of the chemical compounds which exhibit vitamin activity The two major forms are vitamin D₂ or ergocalciferol, and vitamin D₃ or cholecalciferol. Ergocalciferol (Deltalin Eli Lilly and Company) is a form of Vitamin D, also called vitamin D2. Cholecalciferol is a form of Vitamin D, also called vitamin D3.

• Vitamin D₁: molecular compound of ergocalciferol with lumisterol, 1:1
• Vitamin D₂: ergocalciferol or calciferol (made from ergosterol)
• Vitamin D₃: cholecalciferol (made from 7-dehydrocholesterol in the skin). Ergocalciferol (Deltalin Eli Lilly and Company) is a form of Vitamin D, also called vitamin D2. Lumisterol is a naturally occurring compound that is part of the Vitamin D family of Steroid compounds Ergocalciferol (Deltalin Eli Lilly and Company) is a form of Vitamin D, also called vitamin D2. Vitamin D is a group of fat-soluble Prohormones, the two major forms of which are vitamin D2 (or Ergocalciferol) and vitamin D3 (or Ergosterol (ergosta-5722-trien-3β-ol a Sterol, is a biological precursor (a Provitamin) to Vitamin D2. Cholecalciferol is a form of Vitamin D, also called vitamin D3. 7-Dehydrocholesterol is a Zoosterol that functions in the serum as a Cholesterol precursor and is converted to pre- vitamin D3 in
• Vitamin D₄: 22-dihydroergocalciferol
• Vitamin D₅: sitocalciferol (made from 7-dehydrositosterol)

Chemically, the various forms of vitamin D are secosteroids; i. 7-Dehydrositosterol is a Sterol which serves as a precursor for Sitocalciferol ( Vitamin D 5 A secosteroid is a molecule similar to a Steroid but with a "broken" ring e. , broken-open steroids. A steroid is a Terpenoid Lipid characterized by a Carbon skeleton with four fused rings generally arranged in a 6-6-6-5 fashion ^[5] The structural difference between vitamin D₂ and vitamin D₃ is in their side chains. A side chain in Organic chemistry and Biochemistry is a part of a Molecule that is attached to a core structure The side chain of D₂ contains a double bond between carbons 22 and 23, and a methyl group on carbon 24.

Vitamin D₂ is derived from fungal and plant sources, and is not produced by the human body. A fungus (ˈfʌŋgəs is a eukaryotic Organism that is a member of the kingdom Fungi (ˈfʌndʒaɪ Plants are living Organisms belonging to the kingdom Plantae. Vitamin D₃ is derived from animal sources and is made in the skin when 7-dehydrocholesterol reacts with UVB ultraviolet light at wavelengths between 270–300 nm, with peak synthesis occurring between 295-297 nm. 7-Dehydrocholesterol is a Zoosterol that functions in the serum as a Cholesterol precursor and is converted to pre- vitamin D3 in Ultraviolet ( UV) light is Electromagnetic radiation with a Wavelength shorter than that of Visible light, but longer than X-rays In Physics wavelength is the distance between repeating units of a propagating Wave of a given Frequency. ^[6][7] These wavelengths are present in sunlight at sea level when the sun is more than 45° above the horizon, or when the UV index is greater than 3. In Physics wavelength is the distance between repeating units of a propagating Wave of a given Frequency. The UV index is an international standard Measurement of how strong the Ultraviolet (UV Radiation from the Sun is at a particular place on a ^[8] At this solar elevation, which occurs daily within the tropics, daily during the spring and summer seasons in temperate regions, and almost never within the arctic circles, adequate amounts of vitamin D₃ can be made in the skin only after ten to fifteen minutes of sun exposure at least two times per week to the face, arms, hands, or back without sunscreen. The Tropics are centered on the Equator and limited in Latitude by the Tropic of Cancer in the northern hemisphere at approximately 23°26' (23 The Arctic Circle is one of the five major circles of latitude that mark maps of the Earth. With longer exposure to UVB rays, an equilibrium is achieved in the skin, and the vitamin simply degrades as fast as it is generated. ^[1]

In humans, D₃ is as effective as D₂ at increasing the levels of vitamin D hormone in circulation; ^[9] However, in some species, such as rats, vitamin D₂ is more effective than D₃. ^[10] Both vitamin D₂ and D₃ are used for human nutritional supplementation, and pharmaceutical forms include calcitriol (1alpha, 25-dihydroxycholecalciferol), doxercalciferol and calcipotriene. Calcitriol ( INN) (ˌkælsɨˈtraɪɒl/ /ˌkælˈsɨtriːɒl or 125-dihydroxycholecalciferol (abbreviated 125-(OH2D3) (also Calcipotriol ( INN) or calcipotriene ( USAN) is a synthetic derivative of Calcitriol or Vitamin D. ^[11]

Biochemistry

Vitamin D is a prohormone, meaning that it has no hormone activity itself, but is converted to the active hormone 1,25-D through a tightly regulated synthesis mechanism. Production of vitamin D in nature always appears to require the presence of some UV light; even vitamin D in foodstuffs is ultimately derived from organisms, from mushrooms to animals, which are not able to synthesize it except through the action of sunlight at some point in the synthetic chain. For example, fish contain vitamin D only because they ultimately exist on calories from ocean algae which synthesize vitamin D in shallow waters from the action of solar UV.

Production in the skin

The epidermal strata of the skin. Production is greatest in the stratum basale (colored red in the illustration) and stratum spinosum (colored orange).

The skin consists of two primary layers: the inner layer called the dermis, composed largely of connective tissue, and the outer thinner epidermis. The dermis is a layer of Skin beneath the epidermis that consists of Connective tissue, and cushions the body from stress and strain Connective tissue is one of the four types of tissue in traditional classifications (the others being epithelial, Muscle, and Nervous tissue) Epidermis is the outermost layer of the Skin. It forms the waterproof protective wrap over the body's surface and is made up of stratified squamous Epithelium with The epidermis consists of five strata; from outer to inner they are: the stratum corneum, stratum lucidum, stratum granulosum, stratum spinosum, and stratum basale. The stratum corneum ("horny layer" is the outermost layer of the epidermis (the outermost layer of the Skin) For the layer of the Hippocampus, see Stratum lucidum of hippocampus. In Microscopic views of Skin, the stratum granulosum layer of the epidermis lies between the Stratum spinosum, below and the Stratum lucidum In the Skin, the stratum spinosum is a multi-layered arrangement of cuboidal cells that sits beneath the Stratum granulosum. Stratum germinativum (also stratum basale or basal cell layer) is the layer of Keratinocytes that lies at the base of the epidermis immediately

Vitamin D₃ is produced photochemically in the skin from 7-dehydrocholesterol. The skin is the outer covering of living tissue of an animal (or plant 7-Dehydrocholesterol is a Zoosterol that functions in the serum as a Cholesterol precursor and is converted to pre- vitamin D3 in The highest concentrations of 7-dehydrocholesterol are found in the epidermal layer of skin, specifically in the stratum basale and stratum spinosum. ^[6] The production of pre-vitamin D₃ is therefore greatest in these two layers, whereas production in the other layers is reduced.

Synthesis in the skin involves UVB radiation which effectively penetrates only the epidermal layers of skin. Ultraviolet ( UV) light is Electromagnetic radiation with a Wavelength shorter than that of Visible light, but longer than X-rays While 7-Dehydrocholesterol absorbs UV light at wavelengths between 270–300 nm, optimal synthesis occurs in a narrow band of UVB spectra between 295-300 nm. In Physics wavelength is the distance between repeating units of a propagating Wave of a given Frequency. A nanometre ( American spelling: nanometer, symbol nm) ( Greek: νάνος nanos dwarf; μετρώ metrό count) is a Peak isomerization is found at 297 nm. This narrow segment is sometimes referred to as D-UV. ^[12] The two most important factors that govern the generation of pre-vitamin D₃ are the quantity (intensity) and quality (appropriate wavelength) of the UVB irradiation reaching the 7-dehydrocholesterol deep in the stratum basale and stratum spinosum. ^[6]

A critical determinant of vitamin D₃ production in the skin is the presence and concentration of melanin. Melanin is a class of compounds found in the Plant, Animal and Protista kingdoms, where it serves predominantly as a Pigment. Melanin functions as a light filter in the skin, and therefore the concentration of melanin in the skin is related to the ability of UVB light to penetrate the epidermal strata and reach the 7-dehydrocholesterol-containing stratum basale and stratum spinosum. Under normal circumstances, ample quantities of 7-dehydrocholesterol (about 25-50 µg/cm² of skin) are available in the stratum spinosum and stratum basale of human skin to meet the body's vitamin D requirements,^[6] and melanin content does not alter the amount of vitamin D that can be produced. In the Metric system, a microgram is 1/1000000 of a Gram (1 × 10-6 or 1/1000 of a milligram is one of the smallest units of weight/mass commonly used A centimetre ( American spelling: centimeter, symbol cm) is a unit of Length in the Metric system, equal to one hundredth ^[13] Thus, individuals with higher skin melanin content will simply require more time in sunlight to produce the same amount of vitamin D as individuals with lower melanin content. As noted below, the amount of time an individual requires to produce a given amount of Vitamin D may also depend upon the person's distance from the equator and on the season of the year.

Synthesis mechanism (form 3)

1. Vitamin D3 is synthesized from 7-dehydrocholesterol, a derivative of cholesterol, which is then photolyzed by ultraviolet light in 6-electron conrotatory electrocyclic reaction. 7-Dehydrocholesterol is a Zoosterol that functions in the serum as a Cholesterol precursor and is converted to pre- vitamin D3 in Cholesterol is a Lipid found in the Cell membranes and transported in the Blood plasma of all Animals It is an essential component of mammalian Photochemistry, a sub-discipline of Chemistry, is the study of the interactions between Atoms, small Molecules, and light (or Electromagnetic radiation In a conrotatory mode of an electrocyclic reaction (a class of organic Chemical reactions the Substituents located at the termini of a conjugated In Organic chemistry, an electrocyclic reaction is a type of Pericyclic Rearrangement reaction where the net result is one Pi bond being converted The product is pre-vitamin D3. Previtamin D3 is an intermediate in the production of Vitamin D.
2. Pre-vitamin D3 then spontaneously isomerizes to Vitamin D3 in a antarafacial hydride [1,7]Sigmatropic shift. Antarafacial and suprafacial are two topological concepts in Organic chemistry describing the relationship between two simultaneous Chemical bond A Sigmatropic reaction in Organic chemistry is a Pericyclic reaction wherein the net result is one Sigma bond changed to another sigma bond.
3. Whether it is made in the skin or ingested, vitamin D3 (cholecalciferol) is then hydroxylated in the liver to 25-hydroxycholecalciferol (25(OH)D3 or calcidiol) by the enzyme 25-hydroxylase produced by hepatocytes, and stored until it is needed. Hydroxylation is any chemical process that introduces one or more hydroxyl groups (-OH into a compound (or radical thereby oxidizing it The liver is a vital organ in the human body and is present in Vertebrates and some other animals Calcidiol, calcifediol, 25-hydroxycholecalciferol, or 25–hydroxy–vitamin D, is a Prehormone which is produced by the Hepatic Cytochrome P450 family 27 subfamily A polypeptide 1, also known as CYP27A1, is a Vertebrate Gene. Hepatocytes make up 70-80% of the Cytoplasmic mass of the Liver. 25-hydroxycholecalciferol is further hydroxylated in the kidneys by the enzyme 1α-hydroxylase, into two dihydroxylated metabolites, the main biologically active hormone 1,25-dihydroxycholecalciferol (1,25(OH)2D3 or calcitriol) and 24R,25(OH)2D3. The kidneys are complicated organs that have numerous biological roles 25-Hydroxyvitamin D3 1-alpha-Hydroxylase is a Cytochrome P450 enzyme in the Proximal tubule which converts Calcidiol to Calcitriol (the bioactive This conversion occurs in a tightly regulated fashion. Calcitriol is represented below right (hydroxylated Carbon 1 is on the lower ring at right, hydroxylated Carbon 25 is at the upper right end).

Mechanism of action

Once vitamin D is produced in the skin or consumed in food, it is converted in the liver and kidney to form 1,25 dihydroxyvitamin D, (1,25(OH)₂D) the physiologically active form of vitamin D (when "D" is used without a subscript it refers to either D₂ or D₃). The liver is a vital organ in the human body and is present in Vertebrates and some other animals The kidneys are complicated organs that have numerous biological roles Following this conversion, the hormonally active form of vitamin D is released into the circulation, and by binding to a carrier protein in the plasma, vitamin D binding protein (VDBP), it is transported to various target organs. Blood plasma is the Liquid component of Blood, in which the Blood cells are suspended ^[5]

The hormonally active form of vitamin D mediates its biological effects by binding to the vitamin D receptor (VDR), which is principally located in the nuclei of target cells. The calcitriol receptor, also known as the Vitamin D receptor ( VDR) and also known as NR1I1 (nuclear receptor subfamily 1 group I member 1 is a member In Cell biology, the nucleus (pl nuclei; from Latin la ''nucleus'' or la ''nuculeus'' "little nut" or kernel is a membrane-enclosed ^[5] The binding of calcitriol to the VDR allows the VDR to act as a transcription factor that modulates the gene expression of transport proteins (such as TRPV6 and calbindin), which are involved in calcium absorption in the intestine. In the field of Molecular biology, a transcription factor (sometimes called a sequence-specific DNA binding factor is a Protein that binds to specific sequences Gene expression is the process by which inheritable information from a Gene, such as the DNA sequence, is made into a functional Gene product, such TRPV6 is a membrane Calcium channel which is responsible for the first step in Calcium absorption in the Intestine. Calbindin describes Calcium binding Proteins first described as the Vitamin D -dependent Calcium binding proteins in Intestine and

The Vitamin D receptor belongs to the nuclear receptor superfamily of steroid/thyroid hormone receptors, and VDR are expressed by cells in most organs, including the brain, heart, skin, gonads, prostate, and breast. In the field of Molecular biology, nuclear receptors are a class of Proteins found within the interior of cells that are responsible for sensing the presence of Steroid hormone receptors are Intracellular receptors (typically Cytoplasmic that perform Signal transduction for Steroid hormones Steroid In Biology, an organ ( Latin: organum, "instrument tool" from Greek όργανον - organon "organ instrument The brain is the center of the Nervous system in animals All Vertebrates and the majority of Invertebrates have a brain The heart is a muscular organ in all Vertebrates responsible for pumping Blood through the Blood vessels by repeated rhythmic The skin is the outer covering of living tissue of an animal (or plant The gonad is the organ that makes Gametes The gonads in males are the Testes and the gonads in Females are the Ovaries. The prostate (from Greek προστάτης - prostates, literally "one who stands before" "protector" "guardian" is a The breast is the upper Ventral region of an animal’s Torso, particularly that of Mammals including Human beings. VDR activation in the intestine, bone, kidney, and parathyroid gland cells leads to the maintenance of calcium and phosphorus levels in the blood (with the assistance of parathyroid hormone and calcitonin) and to the maintenance of bone content. Calcium (ˈkælsiəm is the Chemical element with the symbol Ca and Atomic number 20 Phosphorus, (ˈfɒsfərəs is the Chemical element that has the symbol P and Atomic number 15 Blood is a specialized Bodily fluid that delivers necessary substances to the body's cells ��such as nutrients and oxygen—and transports Waste products Parathyroid hormone (PTH, or parathormone, is secreted by the Parathyroid glands as a Polypeptide containing 84 Amino acids. Calcitonin is a 32-amino acid linear polypeptide Hormone that is produced in Humans primarily by the parafollicular (also known as C-cells of the Bones are rigid organs that form part of the Endoskeleton of Vertebrates They function to move support and protect the various organs of the body produce ^[14]

The VDR is known to be involved in cell proliferation, differentiation. The term cell growth is used in two different ways in Biology. In Developmental biology, cellular differentiation is the process by which a less specialized cell becomes a more specialized Cell type. Vitamin D also affects the immune system, and VDR are expressed in several white blood cells including monocytes and activated T and B cells. Monocyte is a type of Leukocyte, part of the Human body 's Immune system. T cells belong to a group of White blood cells known as Lymphocytes, and play a central role in Cell-mediated immunity. B cells are Lymphocytes that play a large role in the humoral immune response (as opposed to the cell-mediated immune response, which is governed by ^[11]

Nutrition

Only fish is naturally rich in vitamin D, so much vitamin D intake in the industrialised world is from fortified products including milk, soy milk and breakfast cereals or supplements. Food fortification is the Public health policy of adding Micronutrients (essential trace elements and vitamins to Foodstuffs to ensure that minimum dietary Milk is an opaque white liquid produced by the Mammary glands of female Mammals (including Monotremes. Soy milk (also called soya milk, soybean milk, or soy juice) and sometimes referred to as soy drink/beverage is a beverage made from A breakfast cereal (often simply called cereal is a packaged food product made from Cereal intended to be consumed as part of a Breakfast. ^[1]

A blood calcidiol (25-hydroxy-vitamin D) level is the accepted way to determine vitamin D nutritional status. The optimal level of serum 25-hydroxyvitamin D is 35–55 ng/mL; with some debate among medical scientists for the slightly higher value.

The U. S. Dietary Reference Intake for adequate intake (AI) of vitamin D for infants, children and men and women aged 19–50 is 5 micrograms/day (200 IU/day). The Dietary Reference Intake (or DRI is a system of Nutrition recommendations from the Institute of Medicine (IOM of the US National Academy of Sciences In Pharmacology, the International Unit is a unit of measurement for the amount of a substance based on measured Biological activity or effect ^[15] Adequate intake increases to 10 micrograms/day (400 IU/day) for men and women aged 51–70 and up to 15 micrograms/day (600 IU/day) past the age of 70. These dose rates will be too low during winter months above 30° latitude. In the absence of sun exposure, 1000 IU of cholecalciferol is required daily for children. 4000 IU of vitamin D may be required for adults absent summer UVB. ^[1]

Milk and cereal grains are often fortified with vitamin D.

In light of its apparent health benefits, The Canadian Cancer Society recommends that non-white adults take 1,000 IU daily year-round and whites take that amount in fall and winter. The Canadian Pediatric Society recommends 2,000 IU daily for pregnant and breastfeeding women. ^[16]

In food

Season, geographic latitude, time of day, cloud cover, smog, and sunscreen affect UV ray exposure and vitamin D synthesis in the skin, and it is important for individuals with limited sun exposure to include good sources of vitamin D in their diet. Latitude, usually denoted symbolically by the Greek letter phi ( Φ) gives the location of a place on Earth (or other planetary body north or south of the Smog is a kind of Air pollution; the word "smog" is a Portmanteau of Smoke and Fog. Sunscreen (also known as sunblock or suntan lotion) is a Lotion, spray or other Topical product that absorbs or reflects the Sun 's

In some countries, foods such as milk, yogurt, margarine, oil spreads, breakfast cereal, pastries, and bread are fortified with vitamin D₂ and/or vitamin D₃, to minimize the risk of vitamin D deficiency. Milk is an opaque white liquid produced by the Mammary glands of female Mammals (including Monotremes. Yoghurt, yogurt, yoghourt, youghurt or yogourt (see spelling below is a Margarine (ˈmɑrdʒərɨn /ˈmɑrdʒəriːn/ or /ˈmɑrgəriːn/ as a generic term can indicate any of a wide range of Butter substitutes Cooking oil is purified Fat of Plant or Animal origin which is liquid at room temperature A breakfast cereal (often simply called cereal is a packaged food product made from Cereal intended to be consumed as part of a Breakfast. This article describes Pastry in food For the Distributed Hash Table system see Pastry_(DHT. Bread is a Staple food prepared by Baking a Dough of Flour and Water. ^[17] In the United States and Canada, for example, fortified milk typically provides 100 IU per glass, or one quarter of the estimated adequate intake for adults over the age of 50. ^[1]

Fatty fish, such as salmon, are natural sources of vitamin D.

Fortified foods represent the major dietary sources of vitamin D, as very few foods naturally contain significant amounts of vitamin D.

Natural sources of vitamin D include:^[1]

• Fish liver oils, such as cod liver oil, 1 Tbs. (15 mL) provides 1,360 IU
• Fatty fish species, such as:
  • Herring, 3 oz provides 1383 IU
  • Catfish, 3 oz provides 425 IU
  • Salmon, cooked, 3. This article is about the fish extract for the traditional Newfoundland song see " Cod Liver Oil (song " A tablespoon is a type of Spoon used for serving Measure of volume It is also a measure of Volume used in cooking Herring are small Oily fish of the genus Clupea found in the shallow temperate waters of the North Atlantic, the Baltic Sea, the North This article is about the unit of mass For the unit of force see Pound-force. Catfish ( order Siluriformes) are a very diverse group of bony Fish. This article is about the unit of mass For the unit of force see Pound-force. Salmon is the common name for several species of Fish of the family Salmonidae. 5 oz provides 360 IU
  • Mackerel, cooked, 3. This article is about the unit of mass For the unit of force see Pound-force. Mackerel is a common name applied to a number of different species of Fish, mostly but not exclusively from the family Scombridae. 5 oz, 345 IU
  • Sardines, canned in oil, drained, 1. For the hide and seek-like game see Hide and seek. Sardines, or pilchards, are a group of several types of small Oily 75 oz, 250 IU
  • Tuna, canned in oil, 3 oz, 200 IU
  • Eel, cooked, 3. Tuna, are several Species of ocean-dwelling Fish in the family Scombridae, mostly in the genus Thunnus. True eels ( Anguilliformes) are an order of Fish, which consists of four suborders 19 families 110 Genera and approximately 600 5 oz, 200 IU
• Mushrooms provide over 2700 IU per serving (approx. A mushroom is the fleshy Spore -bearing Fruiting body of a Fungus, typically produced above ground on soil or on its food source 3 oz or 1/2 cup) of vitamin D₂, if exposed to just 5 minutes of UV light after being harvested;^[18] this is one of a few natural food-based sources of vitamin D for vegans. This article is about the unit of mass For the unit of force see Pound-force. Ergosterol (ergosta-5722-trien-3β-ol a Sterol, is a biological precursor (a Provitamin) to Vitamin D2.
• One whole egg, 20 IU

Deficiency

Vitamin D deficiency can result from: inadequate intake coupled with inadequate sunlight exposure, disorders that limit its absorption, conditions that impair conversion of vitamin D into active metabolites, such as liver or kidney disorders, or, rarely, by a number of hereditary disorders. An egg is a round or oval body laid by the female of many animals consisting of an Ovum surrounded by layers of Membranes and an outer casing which acts to nourish Metabolomics is the "systematic study of the unique chemical fingerprints that specific cellular processes leave behind" - specifically the study of their small-molecule metabolite The liver is a vital organ in the human body and is present in Vertebrates and some other animals ^[2] Deficiency results in impaired bone mineralization, and leads to bone softening diseases, rickets in children and osteomalacia in adults, and possibly contributes to osteoporosis. Rickets is a softening of the bones in children potentially leading to fractures and deformity Osteomalacia is the general term for the softening of the bones due to defective Bone mineralization. Osteoporosis is a Disease of Bone that leads to an increased risk of fracture. ^[2]

Diseases caused by deficiency

Calcitriol (1,25-dihydroxycholecalciferol). Calcitriol ( INN) (ˌkælsɨˈtraɪɒl/ /ˌkælˈsɨtriːɒl or 125-dihydroxycholecalciferol (abbreviated 125-(OH2D3) (also Active form. Note extra OH groups at upper right and lower right.

The role of diet in the development of rickets was determined by Edward Mellanby between 1918–1920. Rickets is a softening of the bones in children potentially leading to fractures and deformity Professor Edward Mellanby, GBE, KCB, MD, FRCP, FRS (1884 - 1955 discovered Vitamin D and the role of the vitamin in preventing Year 1918 ( MCMXVIII) was a Common year starting on Tuesday (link will display the full calendar of the Gregorian calendar (or a Common Year 1920 ( MCMXX) was a Leap year starting on Thursday (link will display 1920 of the Gregorian calendar ^[19] In 1921 Elmer McCollum identified an anti-rachitic substance found in certain fats could prevent rickets. Because the newly discovered substance was the fourth vitamin identified, it was called vitamin D. ^[19] The 1928 Nobel Prize in Chemistry was awarded to Adolf Windaus, who discovered the steroid 7-dehydrocholesterol, the precursor of vitamin D. Adolf Otto Reinhold Windaus ( December 25, 1876 &ndash June 9, 1959) was a German Chemist who won a Nobel Prize

Vitamin D deficiency is known to cause several bone diseases^[20] including:

• Rickets, a childhood disease characterized by impeded growth, and deformity, of the long bones. Rickets is a softening of the bones in children potentially leading to fractures and deformity The long bones are those that are longer than they are wide and grow primarily by elongation of the Diaphysis, with an Epiphysis at the ends of the growing Bone The earliest sign of subclinical vitamin D deficiency is Craniotabes, abnormal softening or thinning of the skull. Craniotabes is an abnormal softening or thinning of the skull although normally present in new borns ^[21]
• Osteomalacia, a bone-thinning disorder that occurs exclusively in adults and is characterized by proximal muscle weakness and bone fragility. Osteomalacia is the general term for the softening of the bones due to defective Bone mineralization. In fields of Anatomy, anatomical terms of location are descriptive terms to help identify relative positions or directions within a species
• Osteoporosis, a condition characterized by reduced bone mineral density and increased bone fragility. Osteoporosis is a Disease of Bone that leads to an increased risk of fracture.

Prior to the fortification of milk products with vitamin D, rickets was a major public health problem. In the United States, milk has been fortified with 10 micrograms (400 IU) of vitamin D per quart since the 1930s, leading to a dramatic decline in the number of rickets cases. In Pharmacology, the International Unit is a unit of measurement for the amount of a substance based on measured Biological activity or effect The quart is an imperial and US customary unit of Volume equal to a quarter of a Gallon. The 1930s were described as an abrupt shift to more radical and conservative lifestyles as countries were struggling to find a solution to the Great Depression. ^[14]

Vitamin D malnutrition may also be linked to an increased susceptibility to several chronic diseases such as high blood pressure, tuberculosis, cancer, periodontal disease, multiple sclerosis, chronic pain, depression, schizophrenia, seasonal affective disorder, peripheral artery disease^[22] and several autoimmune diseases including type 1 diabetes (see role in immunomodulation). Hypertension, also referred to as high blood pressure, HTN or HPN, is a medical condition in which the Blood pressure is chronically elevated Tuberculosis (abbreviated as TB for tubercle bacillus or T u' b' erculosis Bacillus --> is a common Cancer (medical term Malignant Neoplasm) is a class of Diseases in which a group of cells display uncontrolled Multiple sclerosis (abbreviated MS also known as disseminated sclerosis or encephalomyelitis disseminata) is an autoimmune condition in which the Major depressive disorder, also known as major depression, unipolar depression, unipolar disorder, clinical depression, or simply depression Schizophrenia ( from the Greek roots schizein (σχίζειν "to split" and phrēn Seasonal affective disorder ( SAD) also known as winter depression, is a Mood disorder in which people who have normal mental health throughout most of the year experience Peripheral vascular disease (PVD also known as peripheral artery disease (PAD or peripheral artery occlusive disease (PAOD is a collator for all Diseases Autoimmune diseases arise from an overactive Immune response of the body against substances and tissues normally present in the body Diabetes mellitus type 1 (Type 1 diabetes Type I diabetes T1D T1DM IDDM juvenile diabetes is a form of Diabetes mellitus. ^[14][23]

Groups at greater risk of deficiency

Vitamin D requirements increase with age, while the ability of skin to convert 7-dehydrocholesterol to pre-vitamin D₃ decreases. ^[24] In addition the ability of the kidneys to convert calcidiol to its active form also decreases with age, prompting the need for increased vitamin D supplementation in elderly individuals. The kidneys are complicated organs that have numerous biological roles One consensus concluded that for optimal prevention of osteoporotic fracture the blood calcidiol concentration should be higher than 30 ng/mL, which is equal to 75 nmol/L. ^[25] One billion people in the world are currently Vitamin D deficient, if 75 nmol/L is used as cutoff value for insufficiency. ^[26][27]

The American Pediatric Association advises vitamin D supplementation of 200 IU/day (5μg/d) from birth onwards. ^[1] (1 IU Vitamin D is the biological equivalent of 0. 025 μg cholecalciferol/ergocalciferol). The Canadian Paediatric Society recommends that pregnant or breastfeeding women consider taking 2000 IU/day, that all babies who are exclusively breastfed receive a supplement of 400 IU/day, and that babies living above 55 degrees latitude get 800 IU/day from October to April. ^[28] Health Canada recommends 400IU/day (10μg/d). ^[29] While infant formula is generally fortified with vitamin D, breast milk does not contain significant levels of vitamin D, and parents are usually advised to avoid exposing babies to prolonged sunlight. Infant formula is an artificial substitute for human Breast milk, designed for Infant consumption Breast milk refers to the Milk produced by a mother to feed her baby Therefore, infants who are exclusively breastfed are likely to require vitamin D supplementation beyond early infancy, especially at northern latitudes. Breastfeeding is the feeding of an Infant or young Child with Breast milk directly from human Breasts, not from a Baby bottle or other ^[29] Liquid "drops" of vitamin D, as a single nutrient or combined with other vitamins, are available in water based or oil-based preparations ("Baby Ddrops(R)" in North America, or "Vigantol(R) oil" in Europe). However, babies may be safely exposed to sunlight for short periods; as little as 10 minutes a day without a hat can suffice, depending on location and season. The vitamin D used for in supplements and infant formula is not distinguishable in efficacy from that produced by the body naturally. The risk of overdose is not present with natural exposure to sunlight, because the skin's capacity to produce vitamin D is self-limiting (skin production is thought to reflect the dose of vitamin D to which our evolution optimized human biology). In contrast, care should be given to limit oral intake for infants to no more than 1000 IU (25 mcg) daily, or for adults no more than 10,000 IU (250 mcg) daily.

Obese individuals may have lower levels of the circulating form of vitamin D, probably because of reduced bioavailability, and are at higher risk of deficiency. Obesity is a condition in which excess Body fat has accumulated to such an extent that health may be negatively affected In Pharmacology, bioavailability is used to describe the fraction of an administered Dose of unchanged drug that reaches the Systemic circulation, one of To maintain blood levels of calcium, therapeutic vitamin D doses are sometimes administered (up to 100,000 IU or 2. 5 mg daily) to patients who have had their parathyroid glands removed (most commonly renal dialysis patients who have had tertiary hyperparathyroidism, but also to patients with primary hyperparathyroidism) or with hypoparathyroidism. In Medicine, dialysis (from Greek "dialusis" meaning dissolution "dia" meaning through and "lusis" meaning loosening is primarily Tertiary hyperparathyroidism is a state of excessive secretion of Parathyroid hormone (PTH after a long period of Secondary hyperparathyroidism and resulting in Primary hyperparathyroidism causes Hypercalcemia (elevated blood calcium levels through the excessive secretion of Parathyroid hormone (PTH usually by an Adenoma In Medicine ( Endocrinology) hypoparathyroidism is decreased function of the Parathyroid glands leading to decreased levels of Parathyroid hormone ^[30] Patients with chronic liver disease or intestinal malabsorption disorders may also require larger doses of vitamin D (up to 40,000 IU or 1 mg (1000 micrograms) daily). Liver disease is a broad term describing any number of Diseases affecting the Liver. Malabsorption is a state arising from abnormality in Digestion or Absorption of food nutrients across the gastrointestinal(GI tract.

The use of sunscreen with a sun protection factor (SPF) of 8 inhibits more than 95% of vitamin D production in the skin. Sunscreen (also known as sunblock or suntan lotion) is a Lotion, spray or other Topical product that absorbs or reflects the Sun 's Sunscreen (also known as sunblock or suntan lotion) is a Lotion, spray or other Topical product that absorbs or reflects the Sun 's ^[14][31] Recent studies showed that, following the successful "Slip-Slop-Slap" health campaign encouraging Australians to cover up when exposed to sunlight to prevent skin cancer, an increased number of Australians and New Zealanders became vitamin D deficient. Slip-Slop-Slap is the name for a Health campaign in Australia exhorting people to "slip on a shirt slop on Sunscreen, and slap on a hat" when they go out For a topic outline on this subject see List of basic Australia topics. Skin cancer is a Malignant growth on the Skin which can have many causes New Zealand is an Island country in the south-western Pacific Ocean comprising two main landmasses (the North Island and the South Island ^[17] Ironically, there are indications that vitamin D deficiency may lead to skin cancer. ^[32] To avoid vitamin D deficiency dermatologists recommend supplementation along with sunscreen use.

The reduced pigmentation of light-skinned individuals tends to allow more sunlight to be absorbed even at higher latitudes, thereby reducing the risk of vitamin D deficiency. For the drug referred to as "pigment" see Black tar heroin. ^[25] However, at higher latitudes (above 30°) during the winter months, the decreased angle of the sun's rays, reduced daylight hours, protective clothing during cold weather, and fewer hours of outside activity, diminish absorption of sunlight and the production of vitamin D. Latitude, usually denoted symbolically by the Greek letter phi ( Φ) gives the location of a place on Earth (or other planetary body north or south of the Because melanin acts like a sun-block, prolonging the time required to generate vitamin D, dark-skinned individuals, in particular, may require extra vitamin D to avoid deficiency at higher latitudes. Melanin is a class of compounds found in the Plant, Animal and Protista kingdoms, where it serves predominantly as a Pigment. Human skin color can range from almost black (due to very high concentrations of the dark brown pigment melanin to nearly colorless (appearing reddish white due to the Blood In June 2007, The Canadian Cancer Society began recommending that all adult Canadians consider taking 1000 IU of vitamin D during the fall and winter months (when typically the country's northern latitude prevents sufficient sun-stimulated production of vitamin D). ^[33] At latitudes below 30° where sunlight and day-length are more consistent, vitamin D supplementation may not be required. ^[8] Individuals clad in full body coverings during all their outdoor activity, most notably women wearing burquas in daylight, are at risk of vitamin D deficiency. A burqa (also Transliterated burkha, burka or burqua) is an enveloping outer garment worn by women in some Islamic traditions for the This poses a lifestyle-related health risk mostly for female residents of conservative Muslim nations in the Middle East, but also for strict adherents in other parts of the world. A Muslim (مسلم pronounced Muslim, not Muzlim) is an adherent of the Religion The Middle East is a Subcontinent with no clear boundaries often used as a synonym to Near East, in opposition to Far East. ^[34]

Overdose

For more details on this topic, see hypervitaminosis D. Hypervitaminosis D is a state of Vitamin D toxicity The recommended daily allowance is 400 IU per day

Vitamin D stored in the human body as calcidiol (25-hydroxy-vitamin D) has a large volume of distribution and a long half-life (about 20 to 29 days). Half-Life (computer-game page here It's already listed in the disambiguation page ^[11] However, the synthesis of bioactive vitamin D hormone is tightly regulated and vitamin D toxicity usually occurs only if excessive doses (prescription forms or rodenticide analogs) are taken. Rodenticides are a category of Pest control Chemicals intended to kill Rodents Single feed baits are chemicals sufficiently ^[35] Although normal food and pill vitamin D concentration levels are too low to be toxic in adults, because of the high vitamin A content in codliver oil, it is possible to reach toxic levels of vitamin A (but not vitamin D) via this route, ^[36] if taken in multiples of the normal dose in an attempt to increase the intake of vitamin D. Vitamin A refers to a family of similarly shaped molecules the Retinoids. This article is about the fish extract for the traditional Newfoundland song see " Cod Liver Oil (song " Most historical cases of vitamin D overdose have occurred due to manufacturing and industrial accidents. ^[37]

Exposure to sunlight for extended periods of time does not cause vitamin D toxicity. ^[37] This is because within about 20 minutes of ultraviolet exposure in light skinned individuals (3–6 times longer for pigmented skin) the concentration of vitamin D precursors produced in the skin reach an equilibrium, and any further vitamin D that is produced is degraded. In a Chemical process, chemical equilibrium is the state in which the chemical activities or Concentrations of the reactants and products have no net change ^[38] Maximum endogenous production with full body exposure to sunlight is 250 µg (10,000 IU) per day. ^[37]

The exact long-term safe dose of vitamin D is not entirely known, but dosages up to 250 micrograms (10,000 IU) /day in healthy adults are believed to be safe. ^[11], and all known cases of vitamin D toxicity with hypercalcemia have involved intake of or over 1,000 micrograms (40,000 IU)/day^[37]. The U. S. Dietary Reference Intake Tolerable Upper Intake Level (UL) of vitamin D for children and adults is 50 micrograms/day (2,000 IU/day), with evidence that this value is too low by a factor of 5. The Dietary Reference Intake (or DRI is a system of Nutrition recommendations from the Institute of Medicine (IOM of the US National Academy of Sciences In adults, sustained intake of 2500 micrograms/day (100,000 IU) can produce toxicity within a few months. ^[2] For infants (birth to 12 months) the tolerable UL is set at 25 micrograms/day (1000 IU/day), and vitamin D concentrations of 1000 micrograms/day (40,000 IU) in infants has been shown to produce toxicity within 1 to 4 months. In the United States, overdose exposure of vitamin D was reported by 284 individuals in 2004, leading to 1 death. ^[39] The Nutrition Desk Reference states "The threshold for toxicity is 500 to 600 micrograms [vitamin D] per kilogram body weight per day. "^[40] The US EPA published an oral LD50 of 619 mg/kg for female rats. ^[41]

Serum levels of calcidiol (25-hydroxy-vitamin D) are typically used to diagnose vitamin D overdose. In healthy individuals, calcidiol levels are normally between 32 to 69 ng/mL (82 to 176 nmol/L), but these levels may be as much as 15-fold greater in cases of vitamin D toxicity. Serum levels of bioactive vitamin D hormone (1,25(OH2)D) are usually normal in cases of vitamin D overdose. ^[2]

Some symptoms of vitamin D toxicity are a result of hypercalcemia (an elevated level of calcium in the blood) caused by increased intestinal calcium absorption. Hypercalcaemia (in American English '''Hypercalcemia''' is an elevated calcium level in the Blood. Vitamin D toxicity is known to be a cause of high blood pressure. ^[42] Gastrointestinal symptoms of vitamin D toxicity can include anorexia, nausea, and vomiting. Anorexia (deriving from the Greek "α(ν-" ( a(n-, a prefix that denotes absence + "όρεξη (orexe = appetite is the decreased sensation Nausea ( Latin: Nausea, Greek:, " Sea-sickness " also called wamble) is the sensation of unease and discomfort These symptoms are often followed by polyuria (excessive production of urine), polydipsia (increased thirst), weakness, nervousness, pruritus (itch), and eventually renal failure. In Medicine, polyuria is a condition characterized by the passage of large volumes of urine (at least 2 Urine is a liquid waste product of the body secreted by the Kidneys by a process of filtration from Blood and Excreted through the Urethra. Polydipsia is a medical symptom in which the patient drinks abnormally large amounts of Fluids The word derives from the Greek πολυδιψία, the Itch ( Latin: pruritus) is an unpleasant Sensation that evokes the desire or Reflex to scratch Renal failure or kidney Other signals of kidney disease including elevated protein levels in the urine, urinary casts, and a build up of wastes in the blood stream can also develop. Urinary casts are cylindrical aggregations of particulate matter that form in the distal Nephron, dislodge and eventually pass into the Urine. ^[2] In one study, hypercalciuria and bone loss occurred in four patients with documented vitamin D toxicity. ^[43] Another study showed elevated risk of ischaemic heart disease when 25D was above 89 ng/mL. Ischaemic or ischemic heart disease (IHD or myocardial ischaemia, is a Disease characterized by reduced blood supply to the heart muscle ^[44]

Vitamin D toxicity is treated by discontinuing vitamin D supplementation, and restricting calcium intake. If the toxicity is severe blood calcium levels can be further reduced with corticosteroids or bisphosphonates. Corticosteroids are a class of Steroid hormones that are produced in the Adrenal cortex. In Pharmacology, bisphosphonates (also called diphosphonates) are a class of drugs that inhibit Osteoclast action and the resorption of bone In some cases kidney damage may be irreversible. ^[2]

Role in immunomodulation

Cholecalciferol (D₃)

The hormonally active form of vitamin D mediates immunological effects by binding to nuclear vitamin D receptors (VDR) which are present in most immune cell types including both innate and adaptive immune cells. Cholecalciferol is a form of Vitamin D, also called vitamin D3. An immune system is a collection of mechanisms within an Organism that protects against Disease by identifying and killing Pathogens and Tumor Immune system|Adaptive immune systemThe innate immune system comprises the cells and mechanisms that defend the host from infection by other organisms in a non-specific manner Immune system|Passive immunity|Innate immune system The adaptive immune system is composed of highly specialized systemic cells and processes that eliminate or prevent Pathogenic The VDR is expressed constitutively in monocytes and in activated macrophages, dendritic cells, NK cells, T and B cells. Monocyte is a type of Leukocyte, part of the Human body 's Immune system. Macrophages ( Greek: "big eaters" from makros "large" + phagein "eat" ( Mø) are cells within the tissues that Dendritic cells (DCs are Immune cells and form part of the Mammalian Immune system. Natural killer cells (or NK cells) are a type of Cytotoxic Lymphocyte that constitute a major component of the Innate immune system. T cells belong to a group of White blood cells known as Lymphocytes, and play a central role in Cell-mediated immunity. B cells are Lymphocytes that play a large role in the humoral immune response (as opposed to the cell-mediated immune response, which is governed by In line with this observation, activation of the VDR has potent anti-proliferative, pro-differentiative, and immunomodulatory functions including both immune-enhancing and immunosuppressive effects. The term cell growth is used in two different ways in Biology. In Developmental biology, cellular differentiation is the process by which a less specialized cell becomes a more specialized Cell type. An immunomodulator is a drug used for its effect on the Immune system. Immunostimulators are substances (drugs and nutrients that stimulate the Immune system by inducing activation or increasing activity of any of its components Immunosuppression involves an act that reduces the activation or Efficacy of the Immune system. ^[45]

Effects of VDR-ligands, such as vitamin D hormone, on T-cells include suppression of T cell activation and induction of regulatory T cells, as well as effects on cytokine secretion patterns. In Biochemistry, a ligand ( latin ligare = to bind is a substance that is able to bind to and form a complex with a Biomolecule Effector cells are a type of Lymphocyte that are actively engaged in secreting antibodies. Regulatory T cells (sometimes known as suppressor T cells) are a specialized subpopulation of T cells that act to suppress activation of the Immune system Cytokines are a category of signalling Proteins and Glycoproteins that like Hormones and Neurotransmitters, are used extensively in cellular ^[46] VDR-ligands have also been shown to affect maturation, differentiation, and migration of dendritic cells, and inhibits DC-dependent T cell activation, resulting in an overall state of immunosuppression. ^[47]

VDR ligands have also been shown to increase the activity of natural killer cells, and enhance the phagocytic activity of macrophages. Phagocytosis is the cellular process of engulfing solid particles by the Cell membrane to form an internal Phagosome, or "food vacuole Macrophages ( Greek: "big eaters" from makros "large" + phagein "eat" ( Mø) are cells within the tissues that ^[11] Active vitamin D hormone also increases the production of cathelicidin, an antimicrobial peptide that is produced in macrophages triggered by bacteria, viruses, and fungi. Members of the cathelicidin family of antimicrobial Polypeptides are characterized by a highly conserved region (cathelin domain and a highly variable cathelicidin peptide domain Antimicrobial peptides (also called host defence peptides are an evolutionarily conserved component of the innate immune response and are found among all classes of life A fungus (ˈfʌŋgəs is a eukaryotic Organism that is a member of the kingdom Fungi (ˈfʌndʒaɪ ^[48] Vitamin D deficiency tends to increase the risk of infections, such as influenza^[49] and tuberculosis^[50][51][52]. Tuberculosis (abbreviated as TB for tubercle bacillus or T u' b' erculosis Bacillus --> is a common In a 1997 study, Ethiopian children with rickets were 13 times more likely to get pneumonia than children without rickets. NOTE This intro is the result of careful NPOV work Please do not make potentially controversial edits to it without first discussing on the talk page Pneumonia is an inflammatory illness of the Lung. Frequently it is described as lung Parenchyma / alveolar inflammation and abnormal ^[53]

These immunoregulatory properties indicate that ligands with the potential to activate the VDR, including supplementation with calcitriol (as well as a number of synthetic modulators), may have therapeutic clinical applications in the treatment of; inflammatory diseases (rheumatoid arthritis, psoriatic arthritis), dermatological conditions (psoriasis, actinic keratosis), osteoporosis, cancers (prostate, colon, breast, myelodysplasia, leukemia, head and neck squamous cell carcinoma, and basal cell carcinoma), and autoimmune diseases (systemic lupus erythematosus, type I diabetes, multiple sclerosis) and in preventing organ transplant rejection. Inflammation ( Latin, inflamatio, to set on fire is the complex biological response of vascular tissues to harmful stimuli such as Pathogens Rheumatoid arthritis ( RA) is a chronic systemic autoimmune disorder that causes the Immune system to attack the Joints, where Psoriatic arthritis (also arthritis psoriatica, arthropathic psoriasis or psoriatic arthropathy) is a type of Inflammatory Arthritis Dermatology (from Greek grc δέρμα derma, "skin" and grc -λογία -logia) is a branch of Medicine dealing with Psoriasis (səˈraɪəsɪs ( suh-RI-uh-sus) is a non-contagious disorder which affects the Skin and Joints It commonly causes red scaly Actinic keratosis (also called solar keratosis, or AK) is a Premalignant condition of thick scaly or crusty patches of skin Cancer (medical term Malignant Neoplasm) is a class of Diseases in which a group of cells display uncontrolled Autoimmune diseases arise from an overactive Immune response of the body against substances and tissues normally present in the body Systemic lupus erythematosus ( SLE or lupus,) is a chronic autoimmune disease that can be fatal though with recent medical advances fatalities are becoming Diabetes mellitus type 1 (Type 1 diabetes Type I diabetes T1D T1DM IDDM juvenile diabetes is a form of Diabetes mellitus. Multiple sclerosis (abbreviated MS also known as disseminated sclerosis or encephalomyelitis disseminata) is an autoimmune condition in which the In Biology, an organ ( Latin: organum, "instrument tool" from Greek όργανον - organon "organ instrument Transplant rejection occurs when a transplanted organ or tissue fails to be accepted by the body of the transplant recipient ^[45] However the effects of supplementation with vitamin D, as yet, remain unclear, and supplementation may be inadvisable for individuals with sarcoidosis and other diseases involving vitamin D hypersensitivity. Sarcoidosis, also called sarcoid (from the Greek sarx, meaning "flesh" or Besnier-Boeck disease, is an immune system disorder characterized ^{[54][37][55][56] [57]}

A 2006 study published in the Journal of the American Medical Association, reported evidence of a link between Vitamin D deficiency and the onset of Multiple Sclerosis; the authors posit that this is due to the immune-response suppression properties of Vitamin D. JAMA The Journal of the American Medical Association is an international peer-reviewed general Medical journal, published 48 times per year by the American Multiple sclerosis (abbreviated MS also known as disseminated sclerosis or encephalomyelitis disseminata) is an autoimmune condition in which the ^[58]

Role in cancer prevention and recovery

The vitamin D hormone, calcitriol, has been found to induce death of cancer cells in vitro and in vivo. Cancer (medical term Malignant Neoplasm) is a class of Diseases in which a group of cells display uncontrolled In vitro ( Latin: within the glass refers to the technique of performing a given experiment in a controlled environment outside of a living Organism In vivo ( Latin: within the living means that which takes place inside an organism. Although the anti-cancer activity of vitamin D is not fully understood, it is thought that these effects are mediated through vitamin D receptors expressed in cancer cells, and may be related to its immunomodulatory abilities. The anti-cancer activity of vitamin D observed in the laboratory has prompted some to propose that vitamin D supplementation might be beneficial in the treatment or prevention of some types of cancer. ^[11]

A search of primary and review medical literature published between 1970 and 2007 found an increasing body of research supporting the hypothesis that the active form of vitamin D has significant, protective effects against the development of cancer. Epidemiological studies show an inverse association between sun exposure, serum levels of 25(OH)D, and intakes of vitamin D and risk of developing and/or surviving cancer. The protective effects of vitamin D result from its role as a nuclear transcription factor that regulates cell growth, differentiation, apoptosis and a wide range of cellular mechanisms central to the development of cancer. ^[59] In 2005, scientists released a metastudy which demonstrated a beneficial correlation between vitamin D intake and prevention of cancer. Year 2005 ( MMV) was a Common year starting on Saturday (link displays full calendar of the Gregorian calendar. In Statistics, a meta-analysis combines the results of several studies that address a set of related research hypotheses Drawing from a meta-analysis of 63 published reports, the authors showed that intake of an additional 1,000 international units (IU) (or 25 micrograms) of vitamin D daily reduced an individual's colon cancer risk by 50%, and breast and ovarian cancer risks by 30%. In Statistics, a meta-analysis combines the results of several studies that address a set of related research hypotheses Colorectal cancer, also called colon cancer or large bowel cancer, includes Cancerous growths in the colon, Rectum and Breast cancer is a Cancer that starts in the cells of the Breast in women and men Ovarian cancer is a cancerous growth arising from an Ovary. The cancer most commonly forms in the lining of the ovary (resulting in epithelial ^[60] Research has also shown a beneficial effect of high levels of calcitriol on patients with advanced prostate cancer. ^[61] A randomized intervention study involving 1,200 women, published in June 2007, reports that vitamin D supplementation (1,100 international units (IU)/day) resulted in a 60% reduction in cancer incidence, during a four-year clinical trial, rising to a 77% reduction for cancers diagnosed after the first year (and therefore excluding those cancers more likely to have originated prior to the vitamin D intervention). ^[62][63] In 2006, a study at Northwestern University found that taking the U. Year 2006 ( MMVI) was a Common year starting on Sunday of the Gregorian calendar. S. RDA of vitamin D (400 IU per day) cut the risk of pancreatic cancer by 43% in a sample of more than 120,000 people from two long-term health surveys. Pancreatic cancer is a malignant tumor of the Pancreas. Each year about 37680 individuals in the United States are diagnosed with this condition and 34290 ^[64][65]

A 2006 study using data on over 4 million cancer patients from 13 different countries showed a marked difference in cancer risk between countries classified as sunny and countries classified as less–sunny for a number of different cancers. ^[66] Research has also suggested that cancer patients who have surgery or treatment in the summer — and therefore make more endogenous vitamin D — have a better chance of surviving their cancer than those who undergo treatment in the winter when they are exposed to less sunlight. ^[67]

However, a large scientific review undertaken by the National Cancer Institute found no link between baseline vitamin D status and overall cancer mortality. The National Cancer Institute (NCI is part of the United States Federal government's National Institutes of Health. They did find that vitamin D was beneficial in preventing colorectal cancer, which showed an inverse relationship with blood levels "80 nmol/L or higher associated with a 72% risk reduction". Colorectal cancer, also called colon cancer or large bowel cancer, includes Cancerous growths in the colon, Rectum and ^[68]

Role in coronary disease prevention

Research indicates that vitamin D may play a role in preventing or reversing coronary disease. Coronary disease (or coronary heart disease) refers to the failure of Coronary circulation to supply adequate circulation to Cardiac muscle and surrounding ^[69] As with cancer incidence, a qualitative inverse correlations was found between coronary disease incidence and serum vitamin D levels of 32. 0 versus 35. 5 ng/mL. ^[70] Cholesterol levels were found to be reduced in gardeners in the UK during the summer months. ^[71] Heart attacks peak in winter and decline in summer in temperate^[72] but not tropical latitudes. Myocardial infarction ( MI or AMI for acute myocardial infarction) also known as a heart attack, occurs when the blood supply ^[73] The issue of vitamin D in heart health has not yet been settled. Exercise may account for some of the benefit attributed to vitamin D, since vitamin D levels are higher in physically active persons. ^[74] Moreover, there may be an upper limit after which cardiac benefits decline. One study found an elevated risk of ischaemic heart disease in Southern India in individuals whose vitamin D levels were above 89 ng/mL. Ischaemic or ischemic heart disease (IHD or myocardial ischaemia, is a Disease characterized by reduced blood supply to the heart muscle ^[75] These sun-living groups results do not generalize to sun-deprived urban dwellers. Among a group with heavy sun exposure, taking supplemental vitamin D may result in blood levels over the ideal range, while urban dwellers not taking supplemental vitamin D may fall under the levels recognized as ideal, and being above or below the preferable levels may cause adverse affects on the health of each group.

Researchers at the Harvard Medical School in Boston reported in Circulation, the Journal of the American Heart Association, January 2008 that vitamin D deficiency is associated with an increase in high blood pressure and cardiovascular risk. Hypertension, also referred to as high blood pressure, HTN or HPN, is a medical condition in which the Blood pressure is chronically elevated This is an article about the rock music band "Circulatory System" Researchers monitored the vitamin D levels, blood pressure and other cardiovascular risk factors of 1739 people, of an average age of 59 years for 5 years. They found that those people with low levels of vitamin D had a 62% higher risk of a cardiovascular event than those with normal vitamin D levels. ^[76]

Notes and References

External links

• Vitamin D Fact Sheet from the U.S.National Institutes of Health
• Vitamin D: An Old Vitamin With New Health Implications
• Vitamin D at the Open Directory Project
• History of Vitamin D
• The Vitamin D Council
• The D Dilemma: How to get enough Vitamin D while preventing UV Damage