VITamin D and OmegA-3 TriaL (VITAL): Fractures, Vitamin D and Genetic Markers

The VITamin D and OmegA-3 TriaL (VITAL; NCT 01169259) is a randomized clinical trial in 25,871 U.S. men and women investigating whether taking daily dietary supplements of vitamin D3 (2000 IU) or omega-3 fatty acids (Omacor® fish oil, 1 gram) reduces the risk of developing cancer, heart disease, and stroke in people who do not have a prior history of these illnesses. This ancillary study is being conducted among participants in VITAL and will examine (1) whether vitamin D reduces incident total, non-vertebral fractures, and hip fractures and (2) whether this reduction is modified by vitamin D levels