Author(s): Francesca Jarrett, Gloria Michelle Ducasa, David B Buller and Marianne Berwick
Due to the strong interest in the role of vitamin D in health, we tried to find data to illustrate the relationship between oral supplementation and change in serum levels of vitamin D. We reviewed the literature of randomized, placebo-controlled trials of oral supplementation and serum levels of vitamin D through 2014. We found 25 informative studies which showed a significant dose-response between oral supplementation and serum levels of vitamin D with an r2 of 0.61.These data are consistent with single studies and meta-analyses.In conclusion, the data show a consistent relationship that appears to be independent of multiple confounders.