THE PRODIGY-5 MICRONUTRIENT FORMULA FOR GENERAL HEALTH: Vitamin A • Vitamin C • Vitamin D • Vitamin E • Vitamin K • Vitamin B6 • Vitamin B12 • Folate • B1 (Thiamin) • B2 (Riboflavin) • B3 (Niacin) 

MICRONUTRIENT FORMULA FOR EYE HEALTH: Lutein • Zeaxanthin • Copper • Zinc 

 

Vitamin D

From Wikipedia, the free encyclopedia
 
 
For other uses, see Vitamin D (disambiguation).
Vitamin D
Drug class
Cholecalciferol-3d.png
Class identifiers
Use Ricketsosteoporosisvitamin D deficiency
ATC code A11CC
Biological target vitamin D receptor
Clinical data
Drugs.com MedFacts Natural Products
External links
MeSH D014807

Vitamin D refers to a group of fat-soluble secosteroids responsible for increasing intestinal absorption of calciumironmagnesiumphosphate, and zinc. In humans, the most important compounds in this group are vitamin D3 (also known as cholecalciferol) and vitamin D2 (ergocalciferol).[1] Cholecalciferol and ergocalciferol can be ingested from the diet and from supplements.[1][2][3] Very few foods contain vitamin D; synthesis of vitamin D (specifically cholecalciferol) in the skin is the major natural source of the vitamin. Dermal synthesis of vitamin D from cholesterol is dependent on sun exposure (specifically UVB radiation).

Vitamin D from the diet or dermal synthesis from sunlight is biologically inactive; activation requires enzymatic conversion (hydroxylation) in the liver and kidney. Evidence indicates the synthesis of vitamin D from sun exposure is regulated by a negative feedback loop that prevents toxicity, but because of uncertainty about the cancer risk from sunlight, no recommendations are issued by the Institute of Medicine (US) for the amount of sun exposure required to meet vitamin D requirements. Accordingly, the Dietary Reference Intake for vitamin D assumes no synthesis occurs and all of a person's vitamin D is from food intake, although that will rarely occur in practice. As vitamin D is synthesized in adequate amounts by most mammals exposed to sunlight[citation needed], it is not strictly a vitamin, and may be considered a hormone as its synthesis and activity occur in different locations. Vitamin D has a significant role in calcium homeostasis and metabolism. Its discovery was due to effort to find the dietary substance lacking in rickets (the childhood form of osteomalacia).[4]

Beyond its use to prevent osteomalacia or rickets, the evidence for other health effects of vitamin D supplementation in the general population is inconsistent.[5][6] The effect of vitamin D supplementation on mortality is not clear, with one meta-analysis finding a decrease in mortality in elderly people,[7] and another concluding no clear justification exists for recommending vitamin D.[8]

In the liver, cholecalciferol (vitamin D3) is converted to calcifediolErgocalciferol (vitamin D2) is converted in the liver to 25-hydroxyergocalciferol (a.k.a. 25-hydroxyvitamin D2 — abbreviated 25(OH)D2). These two specific vitamin D metabolites are measured in serum to determine a person's vitamin D status.[9][10]Part of the calcifediol is converted by the kidneys to calcitriol, the biologically active form of vitamin D.[11]Calcitriol circulates as a hormone in the blood, regulating the concentration of calcium and phosphate in the bloodstream and promoting the healthy growth and remodeling of bone. Calcitriol also affects neuromuscular and immune function.[12]

Types

Name Chemical composition Structure
Vitamin D1 Mixture of molecular compounds of ergocalciferolwith lumisterol, 1:1  
Vitamin D2 ergocalciferol (made from ergosterol) Note double bond at top center.
Vitamin D3 cholecalciferol (made from 7-dehydrocholesterol in the skin). Cholecalciferol.svg
Vitamin D4 22-dihydroergocalciferol 22-Dihydroergocalciferol.svg
Vitamin D5 sitocalciferol (made from 7-dehydrositosterol) Vitamin D5 structure.svg

Several forms (vitamers) of vitamin D exist. The two major forms are vitamin D2 or ergocalciferol, and vitamin D3 or cholecalciferol; vitamin D without a subscript refers to either D2 or D3 or both. These are known collectively as calciferol.[13] Vitamin D2 was chemically characterized in 1931. In 1935, the chemical structure of vitamin D3 was established and proven to result from the ultraviolet irradiation of 7-dehydrocholesterol.[14]

Chemically, the various forms of vitamin D are secosteroids, i.e., steroids in which one of the bonds in the steroid rings is broken.[14] The structural difference between vitamin D2and vitamin D3 is the side chain of D2 contains a double bond between carbons 22 and 23, and a methyl group on carbon 24.

Deficiency

Main article: Vitamin D deficiency

A diet deficient in vitamin D in conjunction with inadequate sun exposure causes osteomalacia (or rickets when it occurs in children), which is a softening of the bones. In the developed world, this is a rare disease.[15][16] However, vitamin D deficiency has become a worldwide problem in the elderly and remains common in children and adults.[17][18] Low blood calcifediol (25-hydroxy-vitamin D) can result from avoiding the sun.[19] Deficiency results in impaired bone mineralization and bone damage which leads to bone-softening diseases,[20][21] including:

Rickets

Rickets, a childhood disease, is characterized by impeded growth and soft, weak, deformed long bones that bend and bow under their weight as children start to walk. This condition is characterized by bow legs,[21] which can be caused by calcium or phosphorus deficiency, as well as a lack of vitamin D; today, it is largely found in low-income countries in Africa, Asia, or the Middle East[22] and in those with genetic disorders such as pseudovitamin D deficiency rickets.[23] Maternal vitamin D deficiency may cause overt bone disease from before birth and impairment of bone quality after birth.[24][25]Nutritional rickets exists in countries with intense year-round sunlight such as Nigeria and can occur without vitamin D deficiency.[26][27] Although rickets and osteomalacia are now rare in Britain, outbreaks have happened in some immigrant communities in which osteomalacia sufferers included women with seemingly adequate daylight outdoor exposure wearing Western clothing.[28] Having darker skin and reduced exposure to sunshine did not produce rickets unless the diet deviated from a Western omnivore pattern characterized by high intakes of meat, fish, and eggs, and low intakes of high-extraction cereals.[29][30][31] The dietary risk factors for rickets include abstaining from animal foods.[28][32] Vitamin D deficiency remains the main cause of rickets among young infants in most countries, because breast milk is low in vitamin D and social customs and climatic conditions can prevent adequate sun exposure. In sunny countries such as Nigeria, South Africa, and Bangladesh, where the disease occurs among older toddlers and children, it has been attributed to low dietary calcium intakes, which are characteristic of cereal-based diets with limited access to dairy products.[31] Rickets was formerly a major public health problem among the US population; in Denver, where ultraviolet rays are about 20% stronger than at sea level on the same latitude,[33]almost two-thirds of 500 children had mild rickets in the late 1920s.[34] An increase in the proportion of animal protein[32][35] in the 20th century American diet coupled with increased consumption of milk[36][37] fortified with relatively small quantities of vitamin D coincided with a dramatic decline in the number of rickets cases.[38] Also, in the United States and Canada, vitamin D-fortified milk, infant vitamin supplements, and vitamin supplements have helped to eradicate the majority of cases of rickets for children with fat malabsorption conditions.[21]

Osteomalacia

Osteomalacia is a disease in adults that results from vitamin D deficiency. Characteristics of this disease are softening of the bones, leading to bending of the spine, bowing of the legs, proximal muscle weakness, bone fragility, and increased risk for fractures.[39] Osteomalacia reduces calcium absorption and increases calcium loss from bone, which increases the risk for bone fractures. Osteomalacia is usually present when 25-hydroxyvitamin D levels are less than about 10 ng/mL.[1] Although the effects of osteomalacia are thought to contribute to chronic musculoskeletal pain,[40] there is no persuasive evidence of lower vitamin D levels in chronic pain sufferers[41] or that supplementation alleviates chronic nonspecific musculoskeletal pain.[42]

Diabetes

A systematic review of 2014 concluded that the available studies show no evidence of vitamin D3 supplementation having an effect on glucose homeostasis or diabetes prevention.[43] A review article of 2016 reported that while there is increasing evidence that Vitamin D deficiency may be a risk factor for diabetes mellitus, over-all evidence regarding vitamin D levels and diabetes mellitus is contradictory, requiring further studies.[44]

Skin pigmentation

Some research shows dark-skinned people living in temperate climates have lower vitamin D levels.[45][46] Dark-skinned people may be less efficient at making vitamin D because melanin in the skin hinders vitamin D synthesis; however, a recent study has found novel evidence that low vitamin D levels among Africans may be due to other reasons.[47] Recent evidence implicates parathyroid hormone in adverse cardiovascular outcomes. Black women have an increase in serum parathyroid hormone at a lower 25(OH)D level than white women.[48] A large-scale association study of the genetic determinants of vitamin D insufficiency in Caucasians found no links to pigmentation.[49][50]

Excess

For more details on this topic, see hypervitaminosis D.

Vitamin D toxicity is rare.[18] It is caused by supplementing with high doses of vitamin D rather than sunlight. The threshold for vitamin D toxicity has not been established; however, the tolerable upper intake level (UL), according to some research, is 4,000 IU/day for ages 9–71.[51] Whereas another research concludes that in healthy adults, sustained intake of more than 1250 μg/day (50,000 IU) can produce overt toxicity after several months and can increase serum 25-hydroxyvitamin D levels to 150 ng/ml and greater;[18][52] those with certain medical conditions, such as primary hyperparathyroidism,[53] are far more sensitive to vitamin D and develop hypercalcemia in response to any increase in vitamin D nutrition, while maternal hypercalcemia during pregnancy may increase fetal sensitivity to effects of vitamin D and lead to a syndrome of mental retardation and facial deformities.[53][54]

A review published in 2015 noted that adverse effects have been reported only at 25(OH)D serum concentrations above 200 nmol/L.[55]

Published cases of toxicity involving hypercalcemia in which the vitamin D dose and the 25-hydroxy-vitamin D levels are known all involve an intake of ≥40,000 IU (1,000 μg) per day.[53]

Research has indicated that Vitamin D toxicity is closely related to a depletion of Vitamin K[56] and that repletion of Vitamin K allows individuals to supplement with higher doses of Vitamin D without the negative calcium-related side effects.

Pregnant or breastfeeding women should consult a doctor before taking a vitamin D supplement. The FDA advised manufacturers of liquid vitamin D supplements that droppers accompanying these products should be clearly and accurately marked for 400 international units (IU). In addition, for products intended for infants, the FDA recommends the dropper hold no more than 400 IU.[57] For infants (birth to 12 months), the tolerable upper limit (maximum amount that can be tolerated without harm) is set at 25 μg/day (1,000 IU). One thousand micrograms per day in infants has produced toxicity within one month.[52] After being commissioned by the Canadian and American governments, the Institute of Medicine (IOM) as of 30 November 2010, has increased the tolerable upper limit (UL) to 2,500 IU per day for ages 1–3 years, 3,000 IU per day for ages 4–8 years and 4,000 IU per day for ages 9–71+ years (including pregnant or lactating women).[51]

Effect of excess

Vitamin D overdose causes hypercalcemia, which is a strong indication of vitamin D toxicity – this can be noted with an increase in urination and thirst. If hypercalcemia is not treated, it results in excess deposits of calcium in soft tissues and organs such as the kidneys, liver, and heart, resulting in pain and organ damage.[18][21][39]

The main symptoms of vitamin D overdose which can occur are those of hypercalcemia:

This is frequently followed by:

Furthermore proteinuriaurinary castsazotemia, and metastatic calcification (especially in the kidneys) may develop.[52]

Other symptoms of vitamin D toxicity include mental retardation in young children, abnormal bone growth and formation, diarrhea, irritability, weight loss, and severe depression.[18][39]

Vitamin D toxicity is treated by discontinuing vitamin D supplementation and restricting calcium intake. Kidney damage may be irreversible. Exposure to sunlight for extended periods of time does not normally cause vitamin D toxicity. The concentrations of vitamin D precursors produced in the skin reach an equilibrium, and any further vitamin D produced is degraded.[53]

Recommended serum levels

Recommendations on recommended 25(OH)D serum levels vary. A 2014 review concluded that the most advantageous serum levels for 25(OH)D appeared to be close to 75 nmol/l.[58] A 2015 review reported that regarding optimal levels, a review of 2004 had recommended that at least 70 nmol/L should be maintained in order to avoid negative health effects, that desirable 25(OH)D levels between 90-120 nmol/l have been reported by another review, but that optimal vitamin D levels are still controversial. The review concluded that ranges from 75 to 100 nmol/L were to be recommended for athletes.[55] Part of the controversy stems from that that numerous studies have found differences in serum levels of 25(OH)D between ethnic groups[59][60]and studies point to genetical as well as environmental to be the reasons behind these variations.[61][62][63][64] Supplementation to achieve these standard levels could cause harmful vascular calcification.[65]

US labs generally report 25(OH)D levels as ng/ml. Other countries often use nmol/l.

An IOM committee concluded a serum 25-hydroxyvitamin D level of 20 ng/ml (50 nmol/l) is desirable for bone and overall health. The dietary reference intakes for vitamin D are chosen with a margin of safety and 'overshoot' the targeted serum value to ensure the specified levels of intake achieve the desired serum 25-hydroxyvitamin D levels in almost all persons. No contributions to serum 25-hydroxyvitamin D level are assumed from sun exposure and the recommendations are fully applicable to people with dark skin or negligible exposure to sunlight.

The Institute found serum 25-hydroxyvitamin D concentrations above 30 ng/ml (75 nmol/l) are "not consistently associated with increased benefit". Serum 25-hydroxyvitamin D levels above 50 ng/ml (125 nmol/l) may be cause for concern.[66] However, the desired range of serum 25-hydroxyvitamin D is between 20 and 50 ng/ml.[66]

The risk of cardiovascular disease is lower when vitamin D ranged from 8 to 24 ng/ml (20 to 60 nmol/l). A "threshold effect" appears to occur once a level of 24 ng/ml (60 nmol/l) has been reached i.e., levels of vitamin D over 24 ng/ml (60 nmol/l) did not show added benefit.[67]

Health effects of supplementation

The effects of vitamin D supplementation on health are uncertain.[6][68] A 2013 review did not find any effect from supplementation on the rates of disease, other than a tentative decrease in mortality in the elderly.[69] Low vitamin D levels may result from disease rather than cause disease.[69]

A United States Institute of Medicine (IOM) report states: "Outcomes related to cancercardiovascular disease and hypertension, and diabetes and metabolic syndrome, falls and physical performance, immune functioning and autoimmune disorders, infections, neuropsychological functioning, and preeclampsia could not be linked reliably with calcium or vitamin D intake and were often conflicting."[66]:5 Some researchers claim the IOM was too definitive in its recommendations and made a mathematical mistake when calculating the blood level of vitamin D associated with bone health.[70]Members of the IOM panel maintain that they used a "standard procedure for dietary recommendations" and that the report is solidly based on the data. Research on vitamin D supplements, including large-scale clinical trials, is continuing.[70]

Mortality

Vitamin D3 supplementation has been tentatively found to lead to a reduced risk of death in the elderly,[7][69] but the effect has not been deemed pronounced or certain enough to make taking supplements recommendable.[8]

Other forms (Vitamin D2, alfacalcidol, and calcitriol) do not appear to have any beneficial effects with regard to the risk of death.[7] High blood levels appear to be associated with a lower risk of death, but it is unclear if supplementation can result in this benefit.[71] Both an excess and a deficiency in vitamin D appear to cause abnormal functioning and premature aging.[72][73][74] The relationship between serum calcifediol level and all-cause mortality is parabolic.[66] Harm from vitamin D appears to occur at a lower vitamin D level in the black population than in the white population.[66]:435

Bone health

In general, no good evidence supports the commonly held belief that vitamin D supplements can help prevent osteoporosis.[8] Its general use for prevention of this disease in those without vitamin D deficiency is thus likely not needed.[75]

For older people with osteoporosis, taking vitamin D with calcium may help prevent hip fractures, but it also slightly increases the risk of stomach and kidney problems.[76] Supplementation with higher doses of vitamin D, in those older than 65 years, may decrease fracture risk.[77] This appears to apply more to people in institutions than those living independently.[78]

Vitamin D deficiency causes osteomalacia (called rickets when it occurs in children). Use of vitamin D in children with normal vitamin D levels does not appear to improve bone density.[79] Beyond that, low serum vitamin D levels have been associated with falls, and low bone mineral density.[80] Taking extra vitamin D, however, does not appear to change the risk.[81]

Because it found mounting evidence for a benefit to bone health, though it had not found good evidence of other benefits, the Food and Drug Administration of the United States has proposed requiring manufacturers to declare the amount of vitamin D on nutrition facts labels, as "nutrients of public health significance". As of August 2015, this is currently still open for public comment.[82]

Athletes who are vitamin D deficient are at an increased risk of stress fractures and/or major breaks, particularly those engaging in contact sports. The greatest benefit with supplementation is seen in athletes who are deficient (25(OH)D serum levels <30 ng/ml), or severely deficient (25(OH)D serum levels <25 ng/ml). Incremental decreases in risks are observed with rising serum 25(OH)D concentrations plateauing at 50 ng/ml with no additional benefits seen in levels beyond this point.[83]

Cancer[edit]

Vitamin D supplements have been widely marketed for their claimed anticancer properties.[84] Associations have been shown in observational studies between low vitamin D levels and the risk of development of certain cancers including colon cancer.[85][86]

It is unclear, however, if taking additional vitamin D in the diet or as supplements affects the risk of cancer. Reviews have described the evidence as being "inconsistent, inconclusive as to causality, and insufficient to inform nutritional requirements"[66] and "not sufficiently robust to draw conclusions".[87]

A 2014 review found that supplements had no significant effect on cancer risk.[8] Another review suggested that vitamin D3 may slightly decrease the risk of death from cancer (one fewer death in 150 people over 5 years), but concerns with the quality of the data were noted.[88]

Insufficient evidence exists to recommend vitamin D supplements for people with cancer, although some evidence suggests hypovitaminosis D may be associated with a worse outcome for some cancers,[89] and that higher 25-hydroxy vitamin D levels at the time of diagnosis are associated with better outcomes.[90]

Cardiovascular disease

Taking vitamin D supplements does not meaningfully reduce the risk of strokecerebrovascular diseasecardial infarction, or ischaemic heart disease.[8]Supplementation has no effect on blood pressure.[91]

Depression

Clinical trials of vitamin D supplementation for depressive symptoms have generally been of low quality and show no overall effect, although subgroup analysis showed supplementation for participants with clinically significant depressive symptoms or depressive disorder had a moderate effect.[92]

Cognition and dementia

A systematic review of clinical studies shows an association between low vitamin D levels, cognitive impairment, and a higher risk of developing Alzheimer's disease. However, lower vitamin D concentrations is also associated with poor nutrition and spending less time outdoors. Therefore, alternative explanations for the increase in cognitive impairment exist and hence a direct causal relationship between vitamin D levels and cognition could not be established.[93]

Immune system

Infectious disease

In general, vitamin D functions to activate the innate and dampen the adaptive immune systems.[94] Deficiency has been linked to increased risk of viral infections, including HIV and influenza.[95][96][97] Low levels of vitamin D appear to be a risk factor for tuberculosis,[98] and historically it was used as a treatment.[99] Evidence is lacking on whether vitamin D reduces risk of respiratory infections in children under five years of age.[100] No clinical trial has been done to assess its effect on preventing other infections such as TB and malaria.

Autoimmune disease

Although tentative data link low levels of vitamin D to asthma, evidence to support a beneficial effect from supplementation is inconclusive.[101] Accordingly, supplementation is not currently recommended for treatment or prevention of asthma.[102]

Vitamin D hypovitaminosis may be a risk factor for multiple sclerosis,[103] but no evidence indicates vitamin D has any clinically significant benefit as a treatment.[104] Further research is needed to determine if the association represents a cause and effect relationship.[105]

Low levels of vitamin D are associated with Crohn's disease and ulcerative colitis.[106] Further studies are required to determine its significance.[106]

Pregnancy

Low levels of vitamin D in pregnancy are associated with gestational diabetespre-eclampsia, and small infants.[107] The benefit of supplements, however, is unclear.[107] Pregnant women who take an adequate amount of vitamin D during gestation may experience positive immune effects.[108] Pregnant women often do not take the recommended amount of vitamin D.[108]

Weight loss

Though hypothesized that supplementation of Vitamin D may be an effective treatment for obesity, studies do not support this.[109]

Mechanism of action

Metabolic activation

 
Calcium regulation in the human body.[110] The role of vitamin D is shown in orange.
 
Liver hydroxylation of cholecalciferol to Calcifediol
 
Kidney hydroxylation of calcifediol to calcitriol

Vitamin D is carried in the bloodstream to the liver, where it is converted into the prohormone calcifediol. Circulating calcifediol may then be converted into calcitriol, the biologically active form of vitamin D, in the kidneys. Following the final converting step in the kidney, calcitriol is released into the circulation. By binding to vitamin D-binding protein, a carrier protein in the plasma, calcitriol is transported to various target organs.[14] In addition to the kidneys, calcitriol is also synthesized by monocyte-macrophages in the immune system. When synthesized by monocyte-macrophages, calcitriol acts locally as a cytokine, defending the body against microbial invaders by stimulating the innate immune system.[111]

Whether it is made in the skin or ingested, cholecalciferol is hydroxylated in the liver at position 25 (upper right of the molecule) to form 25-hydroxycholecalciferol (calcifediol or 25(OH)D). This reaction is catalyzed by the microsomal enzyme vitamin D 25-hydroxylase,[112] which is produced by hepatocytes. Once made, the product is released into the plasma, where it is bound to an α-globulin, vitamin D-binding protein.[113]

Calcifediol is transported to the proximal tubules of the kidneys, where it is hydroxylated at the 1-α position (lower right of the molecule) to form calcitriol (1,25-dihydroxycholecalciferol and abbreviated to 1,25(OH)2D). This product is a potent ligand of the vitamin D receptor, which mediates most of the physiological actions of the vitamin. The conversion of calcifediol to calcitriol is catalyzed by the enzyme 25-hydroxyvitamin D3 1-alpha-hydroxylase, the levels of which are increased by parathyroid hormone (and additionally by low calcium or phosphate).

Biosynthesis[edit]

In the presence of UV radiation, many animals synthesize vitamin D3 from 7-dehydrocholesterol, and many fungi synthesize vitamin D2 from ergosterol.

Photochemistry

 
The photochemistry of vitamin D biosynthesis in animal and fungi
 
Thermal isomerization of previtamin D3 to vitamin D3

The transformation that converts 7-dehydrocholesterol to vitamin D3 occurs in two steps.[114][115] First, 7-dehydrocholesterol is photolyzed by ultraviolet light in a 6-electron conrotatory ring-opening electrocyclic reaction; the product is previtamin D3. Second, previtamin D3 spontaneously isomerizes to vitamin D3 (cholecalciferol) in an antarafacial sigmatropic [1,7] hydride shift. At room temperature, the transformation of previtamin D3 to vitamin D3in an organic solvent takes about 12 days to complete. The conversion of previtamin D3 to vitamin D3 in the skin is about 10 times faster than in an organic solvent [116]

Evolution

Photosynthesis of vitamin D in the ocean by phytoplankton (such as coccolithophore and Emiliania huxleyi) has existed for more than 500 million years and continues to the present. Although primitive vertebrates in the ocean could absorb calcium from the ocean into their skeletons and eat plankton rich in vitamin D, land animals required another way to satisfy their vitamin D requirement for a calcified skeleton without relying on plants. Land vertebrates have been making their own vitamin D for more than 350 million years.[117]

Vitamin D can be synthesized only by a photochemical process, so land vertebrates had to ingest foods that contained vitamin D or had to be exposed to sunlight to photosynthesize vitamin D in their skin to satisfy their vitamin D requirements.[116]

 

Synthesis in the skin

 
In the epidermal strata of the skin, production is greatest in the stratum basale (colored red in the illustration) and stratum spinosum (colored light brown).

Vitamin D3 is produced photochemically from 7-dehydrocholesterol in the skin of most vertebrate animals, including humans.[118] The precursor of vitamin D3, 7-dehydrocholesterol is produced in relatively large quantities. 7-Dehydrocholesterol reacts with UVB light at wavelengths between 270 and 300 nm, with peak synthesis occurring between 295 and 297 nm.[119] These wavelengths are present in sunlight, as well as in the light emitted by the UV lamps in tanning beds (which produce ultraviolet primarily in the UVA spectrum, but typically produce 4% to 10% of the total UV emissions as UVB). Exposure to light through windows is insufficient because glass almost completely blocks UVB light.[120][121]

Adequate amounts of vitamin D can be produced with moderate sun exposure to the face, arms and legs, averaging 5–30 minutes twice per week, or approximately 25% of the time for minimal sunburn. The darker the skin, and the weaker the sunlight, the more minutes of exposure are needed. Vitamin D overdose is impossible from UV exposure; the skin reaches an equilibrium where the vitamin degrades as fast as it is created.[18][122][123]

Sunscreen absorbs or reflects ultraviolet light and prevents much of it from reaching the skin. Sunscreen with a sun protection factor (SPF) of 8 based on the UVB spectrum decreases vitamin D synthetic capacity by 95%, and SPF 15 decreases it by 98%.[124]

The skin consists of two primary layers: the inner layer called the dermis, composed largely of connective tissue, and the outer, thinner epidermis. Thick epidermis in the soles and palms consists of five strata; from outer to inner, they are: the stratum corneumstratum lucidumstratum granulosumstratum spinosum, and stratum basale. Vitamin D is produced in the two innermost strata, the stratum basale and stratum spinosum.

The naked mole-rat appears to be naturally cholecalciferol-deficient, as serum 25-OH vitamin D levels are undetectable.[125] In some animals, the presence of fur or feathers blocks the UV rays from reaching the skin. In birds and fur-bearing mammals, vitamin D is generated from the oily secretions of the skin deposited onto the feathers or fur and is obtained orally during grooming.[126]

Biological activity

 
Synthesis of vitamin D

The active vitamin D metabolite calcitriol mediates its biological effects by binding to the vitamin D receptor (VDR), which is principally located in the nuclei of target cells.[14] 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.[127] The vitamin D receptor belongs to the nuclear receptor superfamily of steroid/thyroid hormone receptors, and VDRs are expressed by cells in most organs, including the brainheart, skin, gonadsprostate, and breast. 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.[38]

One of the most important roles of vitamin D is to maintain skeletal calcium balance by promoting calcium absorption in the intestines, promoting bone resorption by increasing osteoclast number, maintaining calcium and phosphate levels for bone formation, and allowing proper functioning of parathyroid hormone to maintain serum calcium levels. Vitamin D deficiency can result in lower bone mineral density and an increased risk of reduced bone density (osteoporosis) or bone fracturebecause a lack of vitamin D alters mineral metabolism in the body.[128] Thus, although this may initially appear paradoxical, vitamin D is also critical for bone remodeling through its role as a potent stimulator of bone resorption.[128]

The VDR may be involved in cell proliferation and differentiation. Vitamin D also affects the immune system, and VDRs are expressed in several white blood cells, including monocytes and activated T and B cells.[129] In vitro, vitamin D increases expression of the tyrosine hydroxylase gene in adrenalmedullary cells, and affects the synthesis of neurotrophic factorsnitric oxide synthase, and glutathione.[130]

Apart from VDR activation, various alternative mechanisms of action are under study, such as inhibition of signal transduction by hedgehog, a hormone involved in morphogenesis.[131]

History

American researchers Elmer McCollum and Marguerite Davis in 1914[4] discovered a substance in cod liver oil which later was called "vitamin A". British doctor Edward Mellanby noticed dogs that were fed cod liver oil did not develop rickets and concluded vitamin A, or a closely associated factor, could prevent the disease. In 1922, Elmer McCollum tested modified cod liver oil in which the vitamin A had been destroyed.[4] The modified oil cured the sick dogs, so McCollum concluded the factor in cod liver oil which cured rickets was distinct from vitamin A. He called it vitamin D because it was the fourth vitamin to be named.[132][133][134] It was not initially realized that, unlike other vitamins, vitamin D can be synthesised by humans through exposure to UV light.

In 1925,[4] it was established that when 7-dehydrocholesterol is irradiated with light, a form of a fat-soluble vitamin is produced (now known as D3). Alfred Fabian Hess stated: "Light equals vitamin D."[135] Adolf Windaus, at the University of Göttingen in Germany, received the Nobel Prize in Chemistry in 1928 for his work on the constitution of sterols and their connection with vitamins.[136] In 1929, a group at NIMR in Hampstead, London, were working on the structure of vitamin D, which was still unknown, as well as the structure of steroids. A meeting took place with J.B.S. HaldaneJ.D. Bernal, and Dorothy Crowfoot to discuss possible structures, which contributed to bringing a team together. X-ray crystallography demonstrated the sterol molecules were flat, not as proposed by the German team led by Windaus. In 1932, Otto Rosenheim and Harold King published a paper putting forward structures for sterols and bile acids which found immediate acceptance.[137] The informal academic collaboration between the team members Robert Benedict Bourdillon, Otto Rosenheim, Harold King, and Kenneth Callow was very productive and led to the isolation and characterization of vitamin D.[138] At this time, the policy of the Medical Research Council was not to patent discoveries, believing the results of medical research should be open to everybody. In the 1930s, Windaus clarified further the chemical structure of vitamin D.[139]

In 1923, American biochemist Harry Steenbock at the University of Wisconsin demonstrated that irradiation by ultraviolet light increased the vitamin D content of foods and other organic materials.[140] After irradiating rodent food, Steenbock discovered the rodents were cured of rickets. A vitamin D deficiency is a known cause of rickets. Using $300 of his own money, Steenbock patented his invention. His irradiation technique was used for foodstuffs, most memorably for milk. By the expiration of his patent in 1945, rickets had been all but eliminated in the US.[141]

In 1971–72, the further metabolism of vitamin D to active forms was discovered. In the liver, vitamin D was found to be converted to calcifediol. Calcifediol is then converted by the kidneys to calcitriol, the biologically active form of vitamin D.[11] Calcitriol circulates as a hormone in the blood, regulating the concentration of calcium and phosphate in the bloodstream and promoting the healthy growth and remodeling of bone. The vitamin D metabolites, calcifediol and calcitriol, were identified by competing teams led by Michael F. Holick in the laboratory of Hector DeLuca and by Tony Norman and colleagues.[142][143][144]

Guidelines

Dietary reference intakes

Different institutions propose different recommendations concerning daily amounts of the vitamin.The recommended daily intake of vitamin D may not be sufficient if sunlight exposure is limited.[145]

(Conversion : 1 µg = 40 IU and 0.025 µg = 1 IU)[146]

Australia and New Zealand

About a third of Australians have vitamin D deficiency.[147] Australia and New Zealand have established guidelines for dietary vitamin D intake as follows:[148]

Age group Adequate Intake (μg) Upper Level of Intake (μg)
Infants 0–12 months 5.0 25.0
Children 1–18 years 5.0 80.0
Adults 19–50 years 5.0 80.0
Adults 51–70 years 10.0 80.0
Adults > 70 years 15.0 80.0

Canada

According to Health Canada[149] the recommended dietary allowances (RDA) for vitamin D are:

Age group RDA (IU) Tolerable upper intake (IU)
Infants 0–6 months 400* 1,000
Infants 7–12 months 400* 1,500
Children 1–3 years 600 2,500
Children 4–8 years 600 3,000
Children and Adults 9–70 years 600 4,000
Adults > 70 years 800 4,000
Pregnancy & Lactation 600 4,000

Note*: Adequate intake rather than recommended dietary allowance

European Union

The recommended daily amount for vitamin D in the European Union is 5 µg.[150] In 2012, the German Society for Nutrition, a private organisation, increased the recommended daily amount to 20 µg.[151]

The European Menopause and Andropause Society recommended 15 µg (600 IU) until age 70, and 20 µg (800 IU) in older than 71 years, in postmenopausal women. This dose should be increased to 4,000 IU/day in some patients with very low vitamin D status or in case of comorbid conditions.[152]

The UK National Health Service recommends babies and young children aged six months to five years, pregnant or breastfeeding women, and sun-deprived elderly people should take daily vitamin supplements to ensure sufficient vitamin D intake.[153] In July 2016, Public Health England recommended that everyone consider taking a daily supplement containing 10 µg of vitamin D during autumn and winter because of inadequate sunlight for vitamin D synthesis.[154]

United States

According to the United States Institute of Medicine,[66] the recommended dietary allowances (RDA) of vitamin D are:

Age group RDA (IU/day)
Infants 0–6 months 400*
Infants 6–12 months 400*
1–70 years 600 (15 μg/day)
71+ years 800 (20 μg/day)
Pregnant/Lactating 600 (15 μg/day)
  • Asterisk for infants indicates adequate intake (AI) for infants, as an RDA has yet to be established for infants.[66]

For U.S. food and dietary supplement labeling purposes the amount in a serving is expressed as a percent of Daily Value (%DV). For vitamin D labeling purposes 100% of the Daily Value was 400 IU (10 μg), but as of May 2016 it has been revised to 800 IU (20 μg). A table of the pre-change adult Daily Values is provided at Reference Daily Intake. Food and supplement companies have until July 28, 2018 to comply with the change.

Upper intake levels

The tolerable upper intake level is defined as "the highest average daily intake of a nutrient that is likely to pose no risk of adverse health effects for nearly all persons in the general population.[66]:403 " Although tolerable upper intake levels are believed to be safe, information on the long-term effects is incomplete and these levels of intake are not recommended:[66]:403:433

Age group Tolerable upper intake level
Infants 0–6 months 1,000 IU/day (25 µg/day)
Infants 6–12 months 1,500 IU/day (37.5 µg/day)
1–3 years 2,500 IU/day (62.5 µg/day)
4–8 years 3,000 IU/day (75 µg/day)
9+ years 4,000 IU/day (100 µg/day)
Pregnant/lactating 4,000 IU/day[66]:5(100 µg/day)

The dietary reference intake for vitamin D issued by the Institute of Medicine (IOM) in 2010 superseded a previous recommendation which had adequate intake status. The recommendations were formed assuming the individual has no skin synthesis of vitamin D because of inadequate sun exposure. The reference intake for vitamin D refers to total intake from food, beverages and supplements, is intended for the North American population, and assumes that calcium requirements are being met.[66]:5

One school of thought contends the human physiology is fine-tuned to an intake of 4,000–12,000 IU/day from sun exposure with concomitant serum 25-hydroxyvitamin D levels of 40 to 80 ng/ml[155] and this is required for optimal health. Proponents of this view, who include some members of the panel that drafted a now-superseded 1997 report on vitamin D from the IOM, contend the IOM's warning about serum concentrations above 50 ng/ml lacks biological plausibility. They suggest, for some people, reducing the risk of preventable disease requires a higher level of vitamin D than that recommended by the IOM.[155][156]

According to the European Food Safety Authority, the tolerable upper intake levels[157] are:

  • 0–12 months: 25 µg/day (1,000 IU)
  • 1–10 years: 50 µg/day (2,000 IU)
  • 11–17 years: 100 µg/day (4,000 IU)
  • 17+: 100 µg/day (4,000 IU)
  • Pregnant/lactating women: 100 µg/day (4,000 IU)

Allowable health claims

Apart from the above discussion on health effects or scientific evidence for lowering disease risk, governmental regulatory agencies stipulate for the food industry health claims allowable as statements on packaging.

European Food Safety Authority (EFSA)[158]

  • normal function of the immune system
  • normal inflammatory response
  • normal muscle function
  • reduced risk of falling in people over age 60[159]

US Food and Drug Administration (FDA)

  • may reduce the risk of osteoporosis[160]

Health Canada

  • adequate calcium and regular exercise may help to achieve strong bones in children and adolescents and may reduce the risk of osteoporosis in older adults. An adequate intake of vitamin D is also necessary[161]

Other possible agencies with claim guidance: Japan FOSHU[162] and Australia-New Zealand.[163]

Dietary sources

Vitamin D is found in few dietary sources.[1][3][18][21] Sunlight exposure is the primary source of vitamin D for the majority of people, other than supplements.[2]

While some studies have found that vitamin D3 raises 25(OH)D blood levels faster and remains active in the body longer,[164][165] others contend that vitamin D2 sources are equally bioavailable and effective as D3 for raising and sustaining 25(OH)D.[166][167][168]

Vitamin D2

Main article: Ergocalciferol

Mushrooms

Mushrooms are a good dietary source of vitamin D2. They contain high concentrations of ergosterol (provitamin D2), and sunlight or ultraviolet radiation triggers its conversion to viosterol (previtamin D2), which then turns into vitamin D2. Low values in mushrooms for vitamin D2 below indicate no or only incidental exposure to sunlight. When fresh mushrooms or dried powders are purposely exposed to artificial sunlight by use of an industrial ultraviolet lamp, vitamin D2 levels can be concentrated to much higher levels.[166][169][170]

Content of vitamin D2 per 100g:[171]

  • Mushrooms, portobello, exposed to ultraviolet light, raw: Vitamin D2: 11.2 μg (446 IU)
  • Mushrooms, portobello, exposed to ultraviolet light, grilled: Vitamin D2: 13.1 μg (524 IU)
  • Mushrooms, shiitake, dried: Vitamin D2: 3.9 μg (154 IU)
  • Mushrooms, shiitake, raw: Vitamin D2: 0.4 μg (18 IU)
  • Mushrooms, portobello, raw: Vitamin D2: 0.3 μg (10 IU)

Human bioavailability of vitamin D2 from vitamin D2-enhanced button mushrooms via UV-B irradiation is effective in improving vitamin D status and not different from a vitamin D2 supplement.[166][172] Vitamin D2 from UV-irradiated yeast baked into bread or mushrooms is bioavailable and increases blood levels of 25(OH)D.[166]

By visual assessment or using a chromometer, no significant discoloration of irradiated mushrooms, as measured by the degree of "whiteness", was observed.[173] Claims have been made that a normal serving (approx. 3 oz or 1/2 cup, or 60 grams) of fresh mushrooms treated with ultraviolet light have increased vitamin D content to levels up to 80 micrograms or 2700 IU if exposed to just 5 minutes of UV light after being harvested.[169]

Plants

  • Alfalfa (Medicago sativa subsp. sativa), shoot: 4.8 μg (192 IU) vitamin D2, 0.1 μg (4 IU) vitamin D3 (per 100 g).[174]

Vitamin D3

Main article: Cholecalciferol

In some countries, staple foods are artificially fortified with vitamin D.[175]

  • Vegan sources
    • Lichen
      • Cladina arbuscula specimens grown under different natural conditions: The contents of vitamin D3 range from 0.67 to 2.04 μg g⁻¹ dry matter in the thalli of C. arbuscula specimens grown under different natural conditions.[176]
  • Animal sources[171]
    • Fish liver oils, such as cod liver oil, 4.5 g (1 teaspoon) provides 450 IU (100 IU/g)
    • Fatty fish species, such as:
      • Salmon, pink, cooked, dry heat, 100 grams (3.5 oz): 522 IU (5.2 IU/g)
      • Mackerel, Pacific and jack, mixed species, cooked, dry heat, 100 grams (3.5 oz): 457 IU (4.6 IU/g)
      • Tuna, canned in oil, 100 grams (3.5 oz): 269 IU (2.7 IU/g)
      • Sardines, canned in oil, drained, 100 grams (3.5 oz): 193 IU (1.9 IU/g)
    • Cooked egg yolk: 44 IU for a 61 g egg (0.7 IU/g)
    • Beef liver, cooked, braised, 100 grams (3.5 oz): 49 IU (0.5 IU/g)

Industrial production

Vitamin D3 (cholecalciferol) is produced industrially by exposing 7-dehydrocholesterol to UVB light, followed by purification.[177] The 7-dehydrocholesterol is a natural substance in fish organs, especially the liver,[178] or in wool grease (lanolin) from sheep. Vitamin D2 (ergocalciferol) is produced in a similar way using ergosterol from yeast or mushrooms as a starting material.[166][177]

Effects of cooking

Vitamin D content in typical foods is reduced variably by cooking.[179] While the exact rate depends on the cooking process, typically between 10% and 50% of Vitamin D is lost.

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  70. Jump up to:a b Maxmen A (2011). "Nutrition advice: the vitamin D-lemma". Nature475(7354): 23–5. doi:10.1038/475023aPMID 21734684.
  71. Jump up^  Schöttker B, Jorde R, Peasey A, Thorand B, Jansen EH, Groot Ld, Streppel M, Gardiner J, Ordóñez-Mena JM, Perna L, Wilsgaard T, Rathmann W, Feskens E, Kampman E, Siganos G, Njølstad I, Mathiesen EB, Kubínová R, Pająk A, Topor-Madry R, Tamosiunas A, Hughes M, Kee F, Bobak M, Trichopoulou A, Boffetta P, Brenner H, B.; Jorde, R.; Peasey, A.; Thorand; Jansen; Groot; Streppel; Gardiner; Ordóñez-Mena; Perna; Wilsgaard; Rathmann; Feskens; Kampman; Siganos; Njølstad; Mathiesen; Kubínová; Pająk; Topor-Madry; Tamosiunas; Hughes; Kee; Bobak; Trichopoulou; Boffetta; Brenner; Consortium on Health Ageing: Network of Cohorts in Europe the United States (June 17, 2014). "Vitamin D and mortality: meta-analysis of individual participant data from a large consortium of cohort studies from Europe and the United States"BMJ348 (jun17 16): g3656–g3656. doi:10.1136/bmj.g3656PMC 4061380Freely accessiblePMID 24938302.
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  73. Jump up^  Tuohimaa P, Keisala T, Minasyan A, Cachat J, Kalueff A; Keisala; Minasyan; Cachat; Kalueff (2009). "Vitamin D, nervous system and aging". Psychoneuroendocrinology34: S278–86. doi:10.1016/j.psyneuen.2009.07.003PMID 19660871.
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  75. Jump up^  Reid IR, Bolland MJ, Grey A; Bolland; Grey (January 11, 2014). "Effects of vitamin D supplements on bone mineral density: a systematic review and meta-analysis". Lancet383 (9912): 146–55. doi:10.1016/s0140-6736(13)61647-5PMID 24119980.
  76. Jump up^  Avenell, A; Mak, JC; O'Connell, D (14 April 2014). "Vitamin D and vitamin D analogues for preventing fractures in post-menopausal women and older men". The Cochrane database of systematic reviews4 (4): CD000227. doi:10.1002/14651858.CD000227.pub4PMID 24729336.
  77. Jump up^  Bischoff-Ferrari HA, Willett WC, Orav EJ, Oray EJ, Lips P, Meunier PJ, Lyons RA, Flicker L, Wark J, Jackson RD, Cauley JA, Meyer HE, Pfeifer M, Sanders KM, Stähelin HB, Theiler R, Dawson-Hughes B (July 2012). "A pooled analysis of vitamin D dose requirements for fracture prevention". N. Engl. J. Med367 (1): 40–9. doi:10.1056/NEJMoa1109617PMID 22762317.
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  82. Jump up^  Proposed Changes to the Nutrition Facts Label. FDA.gov (2016-05-20)
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  85. Jump up^  Ma, Y; Zhang, P; Wang, F; Yang, J; Liu, Z; Qin, H (1 October 2011). "Association between vitamin D and risk of colorectal cancer: a systematic review of prospective studies.". Journal of Clinical Oncology29 (28): 3775–82. doi:10.1200/jco.2011.35.7566PMID 21876081.
  86. Jump up^  Feldman, D; Krishnan, AV; Swami, S; Giovannucci, E; Feldman, BJ (May 2014). "The role of vitamin D in reducing cancer risk and progression.". Nature reviews. Cancer14 (5): 342–57. doi:10.1038/nrc3691PMID 24705652.
  87. Jump up^  Chung, M; Lee, J; Terasawa, T; Lau, J; Trikalinos, TA (20 December 2011). "Vitamin D with or without calcium supplementation for prevention of cancer and fractures: an updated meta-analysis for the U.S. Preventive Services Task Force.". Annals of Internal Medicine155 (12): 827–38. doi:10.7326/0003-4819-155-12-201112200-00005PMID 22184690.
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Further reading

External links

Source: https://en.wikipedia.org/wiki/Vitamin_D

PRODIGY-5

ALL IN ONE NUTRITIONAL WITH TRANS-ARMOR® NUTRIENT TECHNOLOGY

BREAKTHROUGH TECHNOLOGY IN PRODIGY 5.

THE FIVE UNIQUE ATTRIBUTES

A revolutionary new product featuring five unique attributes that create an all-in-one nutritional experience for everyone, every day. Take advantage of the technology and know-how, and enjoy the benefits of the phytoplankton, antioxidants, vitamins, and energy you can feel in minutes with the new ForeverGreen product: Prodigy-5.

Vitamins in Prodigy-5

We all know that vitamins and minerals are essential to our overall health, yet many of us are left not getting most of the vitamins and minerals we need through our normal eating habits. Prodigy-5 features a unique blend of vitamins and minerals that were each specifically chosen using the best peer reviewed scientific research available to support your general and eye health.  

Technology & Know-how behind Prodigy-5

​Adam Saucedo, M.D., has teamed up with the brilliant mind of Balamurali Ambati, M.D., PhD, MBA to bring you the exclusive TransArmor™ Nutrient Technology, found only in Prodigy-5. The patent-pending TransArmor™ technology increases the transit time of nutrients through the digestive system and primes the body for increased absorption of these nutrients.

Antioxidants in Prodigy-5

Prodigy-5 features natural pomegranate and raspberry for a bold flavor that also delivers powerful antioxidants! Antioxidants help to rid the body of damaging free radicals. Antioxidants become a powerful defense system to these free radicals, which if left unchallenged, can contribute to the cause of a range of health problems. Raspberries and pomegranates, Marine phytoplankton, Curcuma.

Phytoplankton in Prodigy-5

The most fundamental nutrient on the planet, phytoplankton are microscopic plant-based organisms that generate most of the world’s oxygen. Phytoplankton, found naturally in both salt and fresh water, are a viable source of vitamins, minerals, amino acids, and other micronutrients.

Energy of the Prodigy-5

Prodigy-5 features natural green tea extract, which is known to help increase energy and mental focus. It helps provide the alertness associated with caffeine without the jittery side effects! Green tea has a range of health benefits, and also contains powerful antioxidants, making it the perfect way to get a little extra boost with your daily dose of Prodigy-5.

PRODIGY-5 DEVELOPED BY MEDICAL INDUSTRY LEADERS

Prodigy-5 revolutionaly Trans-Armor™ nutrient technology, developed by medical industry leader doctors aids the body in absorbing more of the nutrition than it normally would, thereby increasing efficiencies and overall health.

In addition to this scientifically proven technology, Prodigy-5 is considered an all-in-one nutritional habit.

Dr. Ambati, child prodigy, and ForeverGreen’s own Research Scientist Adam Saucedo have partnered together and developed what is being called the check-mate in the conversation of nutrition, Prodigy-5.

DR. AMBATI

CHILD PRODIGY

Dr. Ambati started calculus at age 4, graduated high school at age 11, pre-med age 13, med-school at 14 and was announced the Guinness Book of World Records holder for youngest doctor at age 17.

DR. ADAM SAUCEDO

RESEARCH SCIENTIST

Dr. Adam Saucedo is ForeverGreen’s own Research Scientist, founder and Chief Medical Adviser of the Center for the Heart and Founder of the New Life Center; the largest eating disorder clinic in the world.

DID YOU KNOW THAT HUMAN STOMACH ACIDS ARE STRONG ENOUGH TO DISSOLVE A RAZOR BLADE?

This means that your stomach acids act like a wall, preventing supplements and nutrients from passing to your blood stream and cells; only a percentage survives. Plain English? Your body gets only a fraction of the nutrients it digests. So, this begs the question, Can it be changed?

Can we use modern science to get more out of the digestive process? The answer is a very exciting yes!

Prodigy-5 with the perfect micro-nutrient formula featuring “Trans-Armor Nutrient Technology” that can quickly deliver the nutrients you need throughout your entire body and has the ability to increase the absorption and utilization of those nutrients to maximize your results. With this ground-breaking technology and formula, Prodigy-5 is the solution to the global problem of malnutrition.

With today’s nutritionally bankrupt foods, and the bodies inability to absorb 100% of even the healthiest whole foods, malnutrition effects every singe one of us. Whether you are healthy, wealthy, poor or starving, every person on this planet needs the nutritional revolution offered in Prodigy-5. It is literally for EVERYONE, EVERY DAY.

Prodigy-5 delivers a new TransArmor™ Nutrition bio-enhancing technology.
See how it works:

Prodigy-5 revolutionaly Trans-Armor™ nutrient technology, developed by medical industry leader doctors aids the body in absorbing more of the nutrition than it normally would, thereby increasing efficiencies and overall health. In addition to this scientifically proven technology, Prodigy-5 is considered an all-in-one nutritional habit.

Prodigy 5 contains the new "Trans-Armor™" delivery technology that provides nutrition and energy at the highest level of absorption to our body's cells, including:

• a micronutrient formula for general health,
• a micronutrient formula for eye health,
• an impressive antioxidant profile,
• an impressive and new bio-enhancing absorption technology


Does not contain artificial sweetners or additives. Sweetened with Pomegranate, Raspberry, and Stevia.

PRODIGY-5 HIGHLIGHT

PHYTOPLANKTON

One of those rare products that contains almost everything you need for life (and the rebuilding of cells) is marine phytoplankton.

Marine phytoplankton are one-cell plants that are too small to be seen individually without the aid of a microscope. Because they are microscopic, the body’s cells can absorb them immediately (bioavailability) and receive all of their valuable nutrients at the same time for maximum effectiveness.

The marine phytoplankton, also known as a “Superfood”, is according to NASA and plenty of scientific researches the most important plant and food in the world as it provides the earth with over 90% of it’s oxygen. Marine phytoplankton is not only an important source of oxygen it is a critical food source for ocean life and apparently, for us too.

There are very few (foods) that provide all, or even most, of the raw materials to make new cells and sustain the existing ones. A complete super food, these amazing plants contain more than 90 nutrients vital for a healthy body.

It contains all nine amino acids that the body cannot make. The essential fatty acids are also present (Omega-3 and Omega-6). Further it contains the most important vitamins and mineral nutrients. For example vitamin C, H, B1, B2, B3, B6, B12, E, selenium, zinc, chromium, magnesium, calcium, nickel, iron and many more. (General informations about vitamins)

These valuable nutrients are essential for the production of healthy new cells. We all have, at one time or another, cellular or energy blockages, whether they be emotional or physical. And, among the functional ingredients identified from marine algae, natural pigments (NPs) have received particular attention.

Some benefits (but not all) of marine phytoplankton include:

Support Cardiovascular Health: The high level of antioxidants, amino acids, and high levels of omega-3 fatty acids are known to support a healthier cardiovascular system.

Promotes Healthy Skin: There are large amounts of bioflavonoids that can remove toxins from skin cells. Marine phytoplankton also contains riboflavin that reduces free radical attacks in skin cells.

Boost the Immune System: Alanine, beta-carotene, bioflavonoids, and vitamin E are all immune system enhancers found in this superfood.

Increase Energy: Marine phytoplankton detoxifies the body, and eliminates toxins from the cells. This will improve your energy and mood levels.

Stabilizes Blood Sugar Levels: Marine phytoplankton is really good for stabilizing blood sugar levels. Chromium helps to prevent and moderate against diabetes. Glutamic acids help to reduce alcohol and sugar cravings. Phenylalanine is a known sugar craving reducer.

Helps with Joint Health: Manganese helps to assist in joint mobility. Omega-6 fatty acids can relieve symptoms of arthritis. Pathogenic acid can reduce morning pain caused by arthritis. It will help a lot with joint mobility, and reducing pain and stiffness.

Liver Support: The arginine is found in this superfood and is known to help detoxify the liver.

Improves Brain Function: The high amount of omega-3 fatty acids improve brain function. The nucleic acids can enhance the memory. Phenylalanine improves mental clarity. Proline increases learning ability. Magnesium helps reduce mood swings.

More information about phytoplankton

PRODIGY-5 HIGHLIGHT

VITAMINS AND MINERALS

MICRONUTRIENT FORMULA FOR GENERAL HEALTH

Vitamin A • Vitamin C • Vitamin D • Vitamin E • Vitamin K • Vitamin B6 • Vitamin B12 • Folate • B1 (Thiamin) • B2 (Riboflavin) • B3 (Niacin)



MICRONUTRIENT FORMULA FOR EYE HEALTH

Lutein • Zeaxanthin • Copper • Zinc

Vitamins have specific role to play in the natural wear and tear of the body. There are many vitamin benefits that have a major impact on our overall health.
Vitamins are divided into two types: fat soluble and water soluble. Fat soluble vitamins (vitamin A, D, E and K) are stored in the fat tissues and liver. They can remain in the body up to six months. When the body requires these, they are transported to the area of requirement within the body with help of special carriers. Water soluble vitamins (B-vitamins and vitamin C) are not stored in the body like the fat soluble ones. They travel in the blood stream and need to be replenished everyday.


Below is a list of the 13 major vitamins and what each does for your body:

Prodigy-5 contains: Vitamin A (Beta-Carotene) is a natural antioxidant. It belongs to a class of pigments known as carotenoids which include the yellow, red and orange pigments that give many vegetables and plants their coloring. Vitamin A has been found to enhance immune system functions by supporting and promoting the activities of white blood cells as well as other immune related cells. It also helps to inhibit free radicals and their damaging effects which have been associated with arthritis, heart disease and the development and progression of malignant cells (cancer). Beta-carotene is a precursor for vitamin A (approximately 6 mg of ß-carotene = 1 mg vitamin A). Beta-carotene is best known for the body’s ability to convert it into retinal, which is essential for good vision and visual health, skin, and immune functions.
Natural sources of beta-carotene include carrots, pumpkin, sweet potato, spinach, kale, collard and turnip greens, and winter squash.

According to the National Institutes on Health, the average adult male should be getting 900mcg of vitamin C each day. Females should be getting 700mg a day. Individuals with special needs (women who are pregnant, smokers) may have different requirements and should consult their health professional.

Prodigy-5 contains: Vitamin B1 (Thiamin) is a water-soluble B-vitamin involved with many cellular functions including carbohydrates metabolism, break down of amino acids, production of certain neurotransmitters and multiple enzyme processes (through the coenzyme thiamin pyrophosphate, or TPP). Thiamin can be found in small amounts in a wide variety of foods. Pork, sunflower seeds, yeast, peas and wheat are a few examples. Very little thiamin is stored within the body and must be consumed on a regular basis. A deficiency may result in weakness, loss of appetite, nerve degeneration and irritability.

Prodigy-5 contains: Vitamin B2 (Riboflavin), like most B-vitamins, is involved in many cellular functions. Riboflavin is important in energy metabolism, folate synthesis, conversion of tryptophan to niacin and acts as important coenzymes (FAD/FMN) involved in many reactions. It can be found in liver, mushrooms, spinach, milk, eggs and grains. Because it is water-soluble, there is minimal storage of riboflavin within the body and when dietary intake is insufficient, deficiency can occur (usually accompanied with other vitamin deficiencies).

Prodigy-5 contains:Vitamin B3 (Niacin), also referred to as nicotinamide and nicotinic acid, is another water-soluble, B-vitamin involved with energy metabolism. The coenzymes of niacin (NAD/NADH/NADP/NADPH) are necessary for ATP synthesis (the body’s main energy source), synthesis of fatty acids and some hormones and the transport of hydrogen atoms. When niacin levels are low, the body can use L-tryptophan (an essential amino acid) to manufacture the vitamin. This process is not ideal, however, as it can rapidly deplete L-tryptophan in the body and take away from its other needs such as maintaining optimal levels of serotonin and melatonin. Niacin can be found in grains, liver, fish and chicken.

Prodigy-5 contains: Vitamin B6 is a water-soluble vitamin which plays a variety of important roles in numerous biological processes. Humans cannot produce vitamin B6 so it must be obtained from the diet. Adequate sources of B6 include meats (salmon, turkey, chicken) and whole grain products, such as spinach, nuts and bananas. There are three forms of vitamin B6: pyridoxal (PL), pyridoxine (PN) and pyridoxamine (PM). Pyridoxal-5′-phosphate (PLP) is the principal coenzyme form and has the most importance in human metabolism. It acts as a cofactor for many enzymatic reactions involving L-tryptophan, including L-tryptophan’s conversion to serotonin, an important neurotransmitter in the brain. Pyridoxal-5′-phosphate is also involved in other enzymatic reactions where other neurotransmitters, such as gamma-aminobutyric acid (GABA), are synthesized. This plays a critical role in the functions of the nervous system.
Regarding cardiovascular health, there is an association between low vitamin B6 intake with increased blood homocysteine levels and increased risk of cardiovascular diseases, which has been documented in several large observational studies. Vitamin B6, along with folic acid, vitamin B5, vitamin B12 and niacin, is involved in cell metabolism, enhances the immune system, supports the functions of the nervous system, aids in carbohydrate metabolism to produce energy and promotes cognitive health. Vitamin B6 is necessary for the conduction of nerve impulses, regulation of steroid hormones, catabolism of glycogen to glucose, heme synthesis, and the synthesis/ metabolism of amino acids and neurotransmitters.

Prodigy-5 contains: Vitamin B12 is a water-soluble vitamin essential for numerous processes in the body. The richest food sources of vitamin B12 include animal products such as meat, poultry and fish. It is not generally present in plant products with the exeption of peanuts and soybeans which absorb vitamin B12 from bacteria-filled nodules growing on the roots of these plants. Cyanocobalamin is the form most commonly used in supplements but it must be converted into methylcoblamin before it can join the metabolic pool and be properly utilized by the body. Vitamin B12 is also available as methylcobalamin, which is the methylated form, allowing it to become active quicker and be more effective. Vitamin B12 is necessary for countless processes within the body; it transfers methyl groups, plays a part in DNA synthesis and regulation, helps facilitate cell synthesis, maturation and division, helps convert homocysteine to methionine playing a role in cardiovascular protection, aids in the proper functioning of the nervous system, participates in the metabolism of carbohydrates, proteins and fats, helps produce SAMe for mood and cognitive health and also helps produce energy.

Prodigy-5 contains: Vitamin C (Ascorbic acid) is a water-soluble antioxidant essential for human health and life. It has been proven necessary for healthy immune responses, wound healing, non-heme iron absorption (coming from grains and vegetables), reduction in allergic responses, development of connective tissue components such as collagen, and for the prevention of diseases. Vitamin C has also been shown to be important for cardiovascular health, reducing free radicalproduction and free radical damage, and good cognitive health and performance.
Due to human’s inability to produce vitamin C, it is essential to ingest sources containing vitamin C on a regular, if not daily basis. Natural sources of vitamin C include oranges, guavas, peppers (green, red, yellow), kiwis, strawberries, cantaloupes, Brussels sprouts, broccoli, and many other fruits and vegetables.

Prodigy-5 contains: Vitamin D is a fat-soluble vitamin essential for normal growth and development, the formation and maintenance of healthy bones and teeth, and influences the absorption and metabolism of phosphorus and calcium. It is necessary for proper muscle functioning, bone mineralization and stability, and multiple immune functions. Primarily the vitamin D used by the body is produced in the skin after exposure to ultraviolet light from sunlight. Lack of exposure to sunlight, reduced ability to synthesize vitamin D in the skin, age, low dietary intake, or impaired intestinal vitamin D absorption can result in deficiency. Deficiency has been associated with rickets (poor bone formation), porous or weak bones (osteopenia, osteoporosis), pain and muscle weakness, increased risk for cardiovascular disease, impaired cognitive health, and the development and progression of malignant cells (cancer).
Natural food sources of vitamin D are few; these foods are eggs from hens that have been fed vitamin D or fatty fish such as herrings, mackerel, sardines and tuna. Due to low vitamin D levels, countries such as the United States and Canada have opted to fortify foods such as milk and other dairy products, margarines and butters, some natural cereal and grain products.
According to the National Institutes on Health, the average adult should be getting 600IU of vitamin D each day. Individuals with special needs (the elderly, women who are pregnant) may have different requirements and should consult their health professional.

Prodigy-5 contains: Vitamin E is one of the most powerful fat-soluble antioxidants in the body. It has been proven to help promote cardiovascular health, enhanced immune system function, aid in skin repair and to protect cell membranes from damage caused by free radicals. Vitamin E contributes to proper blood flow and clotting as well as cognitive health and function.
Natural sources of vitamin E include herbs such as cloves and oregano, whole grains, nuts and seeds, wheat germ, avocado, egg yolks, and vegetables/fruits such as dark leafy greens, peppers (red, yellow, orange, green), tomatoes, and mangos. Other sources are vegetable oils, margarines, and fortified cereals.

Prodigy-5 contains: Folic Acid is water-soluble vitamin important for many aspects of health. Sources of folic acid include dark, green leafy vegetables such as spinach or asparagus, fortified cereals, orange juice and legumes. Folic acid (folate) must go through a series of chemical conversions before it becomes metabolically active to be properly utilized within the body.
Folinic acid is the highly bioavailable, metabolically active derivative of folic acid and does not require the action of the enzyme dihydrofolinate reductase to become active, so it’s not affected by medicines and herbs that inhibit this enzyme. Adequate folate is necessary for proper DNA and RNA synthesis in regards to fetal growth and development. Due to these effects, the U.S. Public Health Service recommends all women capable of becoming pregnant consume 400 mcg of folic acid daily to prevent neural tube defects.
In addition to its clear effects on fetal growth and development, folic acid also plays an important role in cardiovascular health. By aiding in the conversion of homocysteine to methionine, it has been shown to reduce the levels of homocysteine, a sulfur containing amino acid. In the absence of adequate folic acid levels, homocysteine levels increase and high homocysteine levels are associated with atherosclerosis and the reduced circulation of oxygen and nutrients to the heart, ears and other organs. These results have been documented in countless studies. Folic acid, along with vitamin B6, vitamin B5, vitamin B12 and niacin, is involved in cell metabolism, enhances the immune system, supports the functions of the nervous system, aids in carbohydrate metabolism to produce energy and promotes cognitive health.

Prodigy-5 contains: Vitamin K, a generic term for a group of fat soluble vitamins, are involved mostly in the process of blood clotting, but also needed in metabolic pathways of bones and other tissues. The most well known are vitamin K1, also known as phylloquinone, and vitamin K2, known as menaquinone. Vitamin D and vitamin K work together in bone metabolism and development. Vitamin K works against oral anticoagulants such as 4-hidroxikumarin, and excessive vitamin K intake, either through supplementation or a change in diet, can reduce the anticoagulant effect. Vitamin K1 is mainly found in leafy green vegetables (such as spinach, swiss chard and kale), avocado and kiwi fruit; vitamin K2 can be found in meat, eggs, and dairy and is also synthesized by bacteria in the colon.

More information about vitamins

PRODIGY-5 HIGHLIGHT

ANTIOXIDANTS


WHAT ARE OXIDANTS?

Oxidants are free radicals that either our bodies produce or we get from the environment. Our bodies create oxidants as a response to stress or poor diet, or we are exposed to oxidants through environmental factors like pollution. Oxidative damage is a contributing factor to many diseases, including muscle and tissue degeneration, heart disease, diabetes, cancer, and many other health problems.


WHAT ARE FREE RADICALS?

Free radicals are atoms or groups of atoms with an odd (unpaired) number of electrons. They are like bullies that are low in energy and attack healthy cells and steal their energy to satisfy themselves. Free radicals cause damage to our blood vessels, which can lead to deposits of bad cholesterol and block arteries. Free radicals come in many shapes, sizes, and chemical configurations. What they all share is a voracious appetite for electrons, stealing them from any nearby substances that will yield them.

The human body naturally produces free radicals and the antioxidants to counteract their damaging effects. However, in most cases, free radicals far outnumber the naturally occurring antioxidants. In order to maintain the balance, a continuous supplemental source of external antioxidants are necessary in order to obtain the maximum benefits of antioxidants.


WHAT ARE ANTIOXIDANTS AND WHY DO WE NEED THEM?

Antioxidants are the nutrients’ police force! They are free radical scavengers! They get rid of the bullies! Antioxidants are like a million microscopic special ops on a mission to save your body from the inside out. The benefits of antioxidants are very important to good health, because if free radicals are left unchallenged, they can cause a wide range of illnesses and chronic diseases.

WHERE CAN WE FIND ANTIOXIDANTS?

Obtained through our foods and produced by are bodies, antioxidants are a powerful defense system.
Antioxidants can be found in flavonols (found in chocolate), resveratrol (found in wine), Ellagic acid (found in Raspberries and pomegranate), and lycopene (found in tomatoes). Other popular antioxidants include vitamins A (beta-carotene), C, E, and catechins.

GREAT SOURCES OF ANTIOXIDANTS IN PRODIGY-5

Marine phytoplankton, Raspberries, Pomegranates, Curcuma

Raspberries and pomegranates contain one of the most powerful antioxidants known, Ellagic acid. Ellagic acid is a potent natural antioxidant that can be found in raspberries and pomegranates. Ellagic acid has been shown to be an effective anti- mutagen and anti-carcinogen.

Anthocyanins (red flavonoid pigment found in plants) give pomegranates their red color and offer a strong serving of antioxidants. Punicalagins (a type of phenolic compound) specifically support cardiovascular and neurological health. Studies have shown that antioxidants 18. can play a role in reducing the cell damage of free radicals.

ANTIOXIDANTS AND AGING

Antioxidants are powerful molecules that support healthy aging in more ways than one. These potent compounds aid in an overall healthy lifestyle by supporting cellular health. Aging isn’t about your chronological age; it is more about the amount of stress in your life and the the function of your cells!

More information about antioxidants

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PRODIGY 5 PRICES


PRODIGY-5 Single Case
(One case contains 28 serving) prices
$ 75.95
€ 69.11
Prodigy 5 Single DEF small

PRODIGY-5 Double Case 
(One case contains 28 serving) prices
$ 149.95
€ 136.45
Prodigy 5 Double DEF small

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Az eredeti Powerstrips fejlesztőjének, Dr. Minsoo Kim legújabb tapasz fejlesztésére váltottunk:
BEPIC - ALLEVI8 PRO
Nagyobb hatékonyság, jobb ár, megbízhatóbb szállítás!

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We have changed! More efficiency, better price, more reliable delivery!
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Wir haben auf das neueste Produkt des ursprünglichen Entwicklers von Powerstrips, Dr. Minsoo Kim, umgestellt: BEPIC - ALLEVI8 PRO

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Siamo passati all'ultimo prodotto dello sviluppatore originale di Powerstrips, il Dr. Minsoo Kim: BEPIC - ALLEVI8 PRO

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