Public health recommendations do not distinguish between vitamin D2 and vitamin D3, yet disagreement exists on whether these two forms should be considered equivalent. The objective of the present study was to evaluate the effect of a daily physiological dose of vitamin D2 or vitamin D3 on 25-hydroxyvitamin D (25(OH)D) status over the winter months in healthy adults living in Dunedin, New Zeala...

Vitamin D is a known modulator of inflammation. Native dietary vitamin D3 is thought to be bio-inactive, and beneficial vitamin D3 effects are thought to be largely mediated by the metabolite 1,25(OH)2D3. Reduced serum levels of the most commonly measured precursor metabolite, 25(OH)D3, is linked to an increased risk of multiple inflammatory diseases, including: cardiovascular disease, arthriti...

Background and Aims: 25-hydroxy vitamin D3 is recognized to be an essential element for healthy body; however, its deficiency has been identified as a risk factor for thyroid disease, diabetes mellitus and other autoimmune diseases and infectious diseases. Thyroid disease is common in the general population that its prevalence increases proportional to age. Subjects with poorly controlled diabe...

BACKGROUND Numerous observational studies have found supplemental calcium and vitamin D to be associated with reduced risk of common cancers. However, interventional studies to test this effect are lacking. OBJECTIVE The purpose of this analysis was to determine the efficacy of calcium alone and calcium plus vitamin D in reducing incident cancer risk of all types. DESIGN This was a 4-y, pop...

The objective of this study was to determine whether feeding high doses of vitamin D3 7 d before slaughter would increase muscle Ca++ levels and result in more tender loin chops. Market lambs (n = 4 callipyge and 4 normal in Exp. 1, and n = 16 calipyge and 16 normal in Exp. 2) were randomly and equally assigned to feeding groups based on callipyge genotype and experimental diet, (vitamin D3 or ...

BACKGROUND Sarcoidosis associated hypercalcemia (SAHC) may be secondary to excessive levels of 1,25-(OH)2 vitamin D3 produced by autonomous 1-alpha-hydroxylase activity within the granulomas.  The frequency, treatment, and consequences of hypercalcemia remain unclear. STUDY DESIGN AND METHODS Two patient cohorts were studied.  In Cohort 1, the prevalence of hypercalcemia in 1606 sarcoidosis p...

BACKGROUND The relative potency of 25-hydroxyvitamin D3 to vitamin D3 needs to be better defined so that food-composition tables can better reflect the true vitamin D nutritive value of certain foods. OBJECTIVE We performed a randomized, controlled intervention study in apparently healthy, free-living adults to investigate whether the intake of 25-hydroxyvitamin D3 is 5 times more potent in r...

Background and Aims: During recent years, the relationship between vitamin D levels and chronic hepatitis B (CHB) infection has attracted many researchers' attention. However, the results relating to the association of vitamin D levels and HBV infection have been conflicting and there remains a lack of knowledge about the effects of antiviral treatments on vitamin D level. Methods: Eighty-four ...

High doses of the active form of vitamin D3, 1,25-dihydroxyvitamin D3 [1,25(OH)2D3], prevent diabetes in the NOD mouse but also elicit unwanted calcemic side effects. Because immune cells themselves can convert vitamin D3 into 1,25(OH)2D3 locally, we hypothesized that dietary vitamin D3 can also prevent disease. Thus, we evaluated whether dietary administration of high doses of regular vitamin ...