Daily consumption of vitamin D can reduce cancer mortality

Regular daily intake of vitamin D could reduce cancer mortality by 12%, according to an analysis of 14 high-quality studies at the German Cancer Research Center, with this effect most evident in individuals over the age of 70 and in those with vitamin D deficiency. Also, the impact was most evident when vitamin intake was started before a cancer diagnosis.

A daily dose of vitamin D could potentially reduce cancer death rates by twelve percent, according to an analysis of 14 top-level studies involving nearly 105,000 participants at the German Cancer Research Center.

The potential effects of vitamin D supplementation on the development or prognosis of cancer have already been investigated in several studies. Based on current studies, vitamin D3 supplementation probably doesn’t protect against developing cancer, but it could reduce the likelihood of dying from cancer. However, previous studies of cancer mortality have produced very different results, and we were interested in the reasons for this, said Ben Schttker, an epidemiologist at the German Cancer Research Center. By reevaluating all previous studies on the topic, we wanted to help produce solid results on this issue, which is so relevant to population health.

When all 14 studies were pooled, no statistically significant results emerged. However, when the studies were divided according to whether vitamin D3 was taken daily in low doses or higher doses given at longer intervals, a large difference was observed. In the four studies with the rare highest doses, there was no effect on cancer mortality. In contrast, in the summary of the ten daily dosing studies, the researchers determined a statistically significant 12% reduction in cancer mortality.

We observed this 12% reduction in cancer mortality after untargeted administration of vitamin D3 to individuals with and without vitamin D deficiency. We can therefore assume that the effect is significantly higher for those people who are actually vitamin D deficient , says Ben Schttker. He explains the better efficacy of daily doses of vitamin D3 by the more regular bioavailability of the active agent, the hormone 1,25-dihydroxy vitamin D, which is only produced by vitamin D reactions in the body and can presumably inhibit tumor growth.

A more detailed analysis of the studies with daily intake also revealed that people aged 70 and older benefited the most from vitamin D3 therapy. Furthermore, the effect was more evident when vitamin D intake was started before the cancer diagnosis.

Hermann Brenner, epidemiologist and prevention expert at DKFZ, adds: This work underlines the great potential of vitamin D3 administration in the prevention of cancer deaths. Regular intake in low doses is associated with almost negligible risk and very low cost.

Reference: Efficacy of Vitamin D3 Supplementation on Cancer Mortality: Systematic Review and Meta-Analysis of Individual Patient Data from Randomized Controlled Trials by Sabine Kuznia, Anna Zhu, Taisuke Akutsu, Julie E. Buring, Carlos A. Camargo Jr, Nancy R. Cook, Li-Ju Chen, Ting-Yuan David Cheng, Sari Hantunen, I.-Min Lee, JoAnn E. Manson, Rachel E. Neale, Robert Scragg, Aladdin H. Shadyab, Sha Sha, John Sluyter, Tomi -Pekka Tuomainen, Mitsuyoshi Urashima, Jyrki K. Virtanen, Ari Voutilainen, & Ben Schttker, March 31, 2023, Aging Research Reviews.
DOI: 10.1016/j.arr.2023.101923

The current work was supported by German Cancer Aid.