Summary

The first dose response study on multiple doses of vitamin D shows that older Caucasian women need less vitamin D to prevent vitamin D insufficiency than previously thought. This article presentes findings from the Vitamin D Response Study: Effect on Serum 5-Hydroxyvitamin D and Parathyroid Hormone trial, a randomized, double-blind, placebo-controlled trial that involved healthy Caucasian postmenopausal women.