Vitamin D seems to always be in the news these days. Read more to understand the Vitamin D molecule!
Vitamin D, originally called antinachite A (a fat-soluble accessory food factor A), is truly a vitamin ! Vitamins are organic micronutrients whose lack in the diet may cause disease. Vitamin D is converted to an active form (α-25,dihyrdoxyvitamin D₃ or 1,α(OH)₂D₃) within the body (specifically the liver and kidneys). When skin is exposed to sunlight (specifically UVB radiation), vitamin D3 is made within the body. Today, concerns over risk of skin cancer with direct sun exposure suggest it should be managed or avoided and many recommend that vitamin D be obtained with intake of vitamin D through diet and/or supplements (Sources of Vitamin D).
Types of Vitamin D
Vitamin D comes in 2 major forms, known as vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol). Vitamin D3 is a form that is naturally produced in the skin after sunlight exposure or vitamin D is taken in dietary foods. Vitamin D3 is the preferred form for supplementation because it is more effective in raising serum 25(OH) D levels in humans. All Ddrops® brand products contain naturally sourced vitamin D₃. Vitamin D2 is sometimes used as a supplement, it is about half as active in humans and is produced from plant and/or fungal sources.
Vitamin D₃ (cholecalciferol) is naturally produced in the skin of animals and humans after sunlight exposure and also contained in supplements and fortified food supplements and fortified foods. Cholecalciferol is the raw material needed by the body to produce a hormone. This form is not yet active in the body, and must be transformed by the liver and kidneys to the active hormone.
Vitamin D₂ (ergocalciferol) is the form that is produced from plant and/or fungal sources. It is sometimes used to fortify foods or used as a supplement. Vitamin D₂ is about one half as potent in the human body as vitamin D₃and still requires activation by the liver and kidneys.
25-hydroxyvitain D or 25(OH)D₃(calcidiol) is produced form vitamin D automatically by the liver. It is the most abundant form of vitamin D in the blood and is the best measure of vitamin D status. Serum 25(OH) D₃ is measured in blood tests to determine a person’s vitamin D nutritional status vitamin D nutritional status. This form is actually not active in the body, but it is an intermediate metabolite.
1α-25,dihyrdoxyvitamin D₃ or 1,α(OH)₂D₃ is an active form within the body made in the kidneys from circulating 25(OH)D₃ in the blood. Blood levels of1,α(OH)₂D₃ are not good markers of vitamin D deficiency and tests are often difficult to interpret. When 1,α(OH)₂D₃ binds with the vitamin D receptor (VDR) it acts like a switch that turns on a number of genetic activities. Researchers have discovered over 200 target genes for 1,α(OH)₂D₃ . Most organs in the body contain VDRs and are responsive to 1,α(OH)₂D₃. Most organs in the body contain VDRs and are responsive to 1,α(OH)₂D₃.
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