Vitamin D Reduces Hepcidin Concentrations Independent of Inflammatory Cytokines in Healthy Adults: A Pilot, Randomized, Double-Blind, Placebo-Controlled Trial of High-Dose Vitamin D3

ObjectiveDisturbances in iron recycling may result from elevations in pro-inflammatory cytokines and hepcidin, the major iron-regulatory hormone. In vitro studies suggest that vitamin D may reduce hepcidin and pro-inflammatory cytokines, and vitamin D deficiency is associated with increased odds of anemia of inflammation. However, data from clinical trials assessing the vitamin D-mediated effects on iron recycling in healthy individuals are lacking. Our objectives were to: 1) examine the effect of high-dose vitamin D on plasma hepcidin, inflammatory cytokine, and ferritin concentrations in healthy adults; and 2) determine whether any observed changes in hepcidin were concomitant with or independent of changes in pro-inflammatory cytokines. MethodsThis was a pilot, double-blind, placebo-controlled trial in healthy adults (N=28) randomized to receive a one-time oral dose of 250,000 IU of vitamin D3 or placebo. Between-and within-group differences in plasma hepcidin, pro-inflammatory cytokine [interleukin (I...