Vitamin D: Extraskeletal Health
Vitamin D deficiency is the most common nutritional deficiency and likely the most common medical condition in the world. The major cause of vitamin D deficiency has been the lack…
RHEUMATOLOGY
Vitamin D and the Immune System: New Perspectives on an Old Theme
Interaction with the immune system is one of the most well-established nonclassic effects of vitamin D. For many years this was considered to be a manifestation of granulomatous diseases such…
Vitamin D in Kidney Disease: Pathophysiology and the Utility of Treatment
Vitamin D physiology has gained more importance and publicity than any of its counterparts in the water- and fat-soluble vitamin groups combined. This is partly because vitamin D deficiency is…
Vitamin D and Fracture Prevention
This article discusses the amount of vitamin D supplementation needed and the desirable 25-hydroxyvitamin D level to be achieved for optimal fracture prevention. Vitamin D modulates fracture risk in 2…
Genetic Disorders and Defects in Vitamin D Action
Two rare genetic diseases can cause rickets in children. The critical enzyme to synthesize calcitriol from 25-hydroxyvitamin D, the circulating hormone precursor, is 25-hydroxyvitamin D-1α-hydroxylase (1α-hydroxylase). When this enzyme is…
Low Vitamin D Status: Definition, Prevalence, Consequences, and Correction
Vitamin D is obtained from cutaneous production when 7-dehydrocholesterol is converted to vitamin D 3 (cholecalciferol) by ultraviolet B radiation or by oral intake of vitamin D 2 (ergocalciferol) and…
Osteomalacia as a Result of Vitamin D Deficiency
Osteomalacia is an end-stage bone disease of chronic and severe vitamin D or phosphate depletion of any cause. Its importance has increased because of the rising incidence of vitamin D…
Maternal Vitamin D Status: Implications for the Development of Infantile Nutritional Rickets
The mother is the major source of circulating 25-OHD concentrations in the young infant. Thus maternal vitamin D status is an important factor in determining the vitamin D status of…
Assessment and Interpretation of Circulating 25-Hydroxyvitamin D and 1,25-Dihydroxyvitamin D in the Clinical Environment
The unique cis -triene structure of vitamin D and related metabolites makes it susceptible to oxidation, ultraviolet (UV) light-induced conformational changes, heat-induced conformational changes, and attacks by free radicals. Vitamin…
The Vitamin D Receptor: New Paradigms for the Regulation of Gene Expression by 1,25-Dihydroxyvitamin D 3
The actions of the vitamin D hormone 1,25-dihydroxyvitamin D 3 (1,25(OH) 2 D 3 ) are mediated by the vitamin D receptor (VDR), a ligand-activated transcription factor that functions to…
