Bottom Line: Monthly high-dose vitamin D supplementation without calcium for up to four years wasn't associated with reduced cancer risk among adults in New Zealand. This study analyzed data from a randomized clinical trial that included a placebo group. There were 328 total cases of cancer, with 165 among 2,558 participants (6.5 percent) who received monthly high-dose vitamin D supplementation and 163 among 2,550 participants (6.4 percent) in the placebo group. This study suggests monthly high-dose vitamin D supplementation should not be used for cancer prevention.
Authors: Robert Scragg, M.B.B.S., Ph.D., of the University of Auckland, New Zealand, and coauthors
To Learn More: The full study is available on the For The Media website.
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