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Vitamin D and Omega-3 Trial (VITAL)

Trial Status: closed to accrual

The VITamin D and OmegA-3 TriaL (VITAL) 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. The 5-year intervention phase (study pill-taking, median 5.3 years) has ended; post-intervention observational follow-up of study participants is ongoing.