The VITAL: Vitamin D, Fractures, and Genetic Markers is an ancillary study of the parent VITAL trial (VITamin D and OmegA-3 TriaL). The study will require the adjudication of all self-reported incident fracture events among 25,871 men and women. Findings from this ancillary study will inform clinical practice on the role(s) of vitamin D supplements in fracture prevention. This proposal will generate important positive or informative negative results about effects of supplemental vitamin D3 alone on fracture risk, while also elucidating the relative importance of vitamin D biomarkers and genetic variations in vitamin D-related pathways on bone. Findings from the proposed ancillary study have the potential for major clinical as well as public health impact for both men and women in the U.S.
