Vitamin+D

Although vitamin D is commonly called a [|vitamin], it is not in the sense an essential dietary vitamin as it can be synthesized in adequate amounts by all mammals from sunlight. Vitamin D fits within the definition of vitamin as it is "an organic compound required as a vital nutrient in tiny amounts by an organism." An organic chemical compound (or related set of compounds) is called a vitamin when it cannot be synthesized in sufficient quantities by an organism, and must be obtained from the diet. As with other compounds called vitamins, it was discovered in an effort to find the dietary substance that was lacking in a disease, namely, [|rickets], the childhood form of [|osteomalacia]. [|[1]] Additionally, like other compounds called vitamins, in the developed world vitamin D is added to staple foods, such as milk, to avoid disease due to deficiency. Measures of [|serum] levels (from a [|vitamin D3 blood test] ) reflect [|endogenous] synthesis from exposure to [|sunlight] as well as intake from the diet, and it is believed that synthesis may contribute generally to the maintenance of adequate serum concentrations. The evidence indicates that the synthesis of vitamin D from sun exposure works in a feedback loop that prevents toxicity but, because of uncertainty about the cancer risk from sunlight, no recommendations are issued by the [|Institute of Medicine], USA, for the amount of sun exposure required to meet vitamin D requirements. Accordingly, the [|Dietary Reference Intakes] for vitamin D assume that no synthesis occurs and that all of a person's vitamin D is from their diet, although that will rarely occur in practice. Vitamin D is converted to [|calcidiol] in the liver. Part of the calcidiol is converted by the kidneys to [|calcitriol], the biologically active form of vitamin D. This 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. Calcidiol is also converted to calcitriol outside of the kidneys for other purposes, such as the proliferation, differentiation and apoptosis of cells; calcitriol also affects neuromuscular function and inflammation. [|[2]] Beyond its use to prevent [|osteomalacia] or [|rickets], the evidence for other health effects of vitamin D supplementation in the general population is inconsistent. [|[3]] [|[4]] The best evidence of benefit is for bone health [|[5]] and a decrease in mortality in elderly women. [|[6]]
 * Vitamin D** is a group of fat-soluble [|secosteroids] . In humans, vitamin D is unique because it can be ingested as cholecalciferol (vitamin D3) or ergocalciferol (vitamin D2) and because the body can also synthesize it (from cholesterol) when sun exposure is adequate (hence its nickname, the "sunshine vitamin").

Vitamin D controls the levels of calcium ions and phosphates in the blood in the intestines it helps bones grow, teeth strengthen, and both of those form vitamin d is also good for your immune system fish oil, liver oil and milk are all good sources for vitamin d the sunlight is the most common source of it vitamin d plays an important role in insulin secretion as well the intake of a sufficient amount of vitamin d also reduces the risk of high blood pressure