Vitamin D₃ Supplements Not Tied to Lower Cancer Mortality, Overall

WEDNESDAY, May 31, 2023 (HealthDay News) — Daily vitamin D₃ supplementation may reduce cancer mortality for some patients, according to a study published in the June issue of Ageing Research Reviews.

Sabine Kuznia, from the German Cancer Research Center in Heidelberg, Germany, and colleagues conducted a systematic review and meta-analysis to evaluate the effect of vitamin D₃ supplementation on cancer mortality in the general population and on prognosis in cancer patients.

Based on 14 randomized controlled trials (104,727 participants; 2,015 cancer deaths), the researchers found a nonsignificant reduction in cancer mortality (risk ratio [RR], 0.94; 95 percent confidence interval [CI], 0.86 to 1.02). However, for the daily vitamin D₃ group (10 trials), there was lower cancer mortality versus placebo (RR, 0.88; 95 percent CI, 0.78 to 0.98). No mortality benefit was seen for a bolus regimen (RR, 1.07; 95 percent CI, 0.91 to 1.24; P value for interaction = 0.042). Similar results were seen for a meta-analysis using individual patient data. The most benefit from daily vitamin D₃ supplementation trials was seen for adults aged 70 years and older (RR, 0.83; 95 percent CI, 0.77 to 0.98) and participants with vitamin D₃ therapy initiation before cancer diagnosis (RR, 0.87; 95 percent CI, 0.69 to 0.99).

“This work underlines the great potential of vitamin D₃ administration in the prevention of cancer deaths,” a coauthor said in a statement. “Regular intake at low doses is associated with almost negligible risk and very low cost.”

One author disclosed ties to the dietary supplements industry.