Although there is no conclusive evidence, previous research suggests a link between vitamin D deficiency and cancer risk in humans.
Researchers investigated this by analyzing a dataset from 1.5 million Danish citizens. This revealed a link between low vitamin D levels and increased cancer risk. Another study of this group of patients with the disease also suggests that those with higher vitamin D levels2 are more likely to benefit from immune-based cancer treatments.
Although Bacteroides fragilis is also present in the human microbiome, further research is needed to determine whether vitamin D contributes to any immunological resistance to cancer in the same way.
Scientists at the US National Institutes of Health’s (NIH) National Cancer Institute (NCI), the Francis Crick Institute, and Denmark’s Aalborg University have found that vitamin D promotes the development of certain types of gut bacteria in mice. They discovered that it promotes the improvement of intestinal bacteria. their resistance to cancer.
Mice fed a vitamin D-enriched diet had stronger immune resistance to experimentally implanted tumors and increased response to immunotherapy treatment, researchers said. Gene editing to remove a protein that binds vitamin D in the blood also had this effect.
The research group found, rather surprisingly, that vitamin D stimulates intestinal epithelial cells and increases the number of bacteria known as Bacteroides fragilis. The growth of tumors transplanted into the mice was reduced, suggesting that the bacteria improved the mice’s resistance to cancer. However, the exact mechanism is still unclear.
We fed Bacteroides fragilis to mice on a normal diet to see if Bacteroides fragilis alone improves cancer immunity. Furthermore, these mice showed greater resistance to tumor formation. However, this was not the case when the mice were fed a diet low in vitamin D.
Lead author Caetano Reis e Sousa, Director of the Institute of Immunobiology at Crick University, said: “What we showed here was surprising: Vitamin D can modulate the gut microbiome to favor certain types of bacteria that give mice better immunity against cancer. .”
“While this may one day be important for human cancer treatment, we do not know how and why vitamin D exerts this effect through the microbiome. Further research is needed before we can conclusively say that improvements are effective in preventing or treating cancer.”
Evangelos Giampazorias, former post-doctoral research fellow at Crick University and currently group leader of the Cancer Immunosurveillance Group at the Manchester Institute of Cancer Research UK, said: “Practical identification of the factors that differentiate a ‘good’ microbiome from a ‘bad’ microbiome is a major challenge. We found that vitamin D helps gut bacteria induce cancer immunity and that found to improve response.
“The key question we are currently trying to answer is how exactly vitamin D supports a ‘good’ microbiome. Answering this could reveal new ways in which the microbiome influences the immune system, offering exciting possibilities in cancer prevention and treatment. ”
Romina Goldschmid, a Stadtmann researcher at the NCI Cancer Research Center, said: “These findings contribute to the growing body of knowledge about the role of the microbiome in cancer immunity and the potential for dietary interventions to fine-tune this relationship to improve patient outcomes.” Further research is needed to fully understand the underlying mechanisms and how they can be exploited to develop individualized treatment strategies.”
Dr Nisharnthi Duggan, Research Information Manager at Cancer Research UK, said: “We know that vitamin D deficiency can cause health problems, but there is not enough evidence linking vitamin D levels to cancer risk. This early-stage study in mice Combined with analysis of population data, we aim to address gaps in the evidence.The findings suggest a possible link between vitamin D and the immune response to cancer. , further research is required to confirm this.
‘Exposure to a little sunlight can help our bodies produce vitamin D, but we don’t need sunbathing to accelerate this process. Just spending short periods of time in the sun can produce enough vitamin D. Vitamin D can also be obtained through diet and supplements, and we know that staying safe in the sun can reduce your risk of cancer. “When the sun is shining, seek shade, cover up, and wear sunscreen.”
Reference magazines:
- References: Giampazolias, E. et al. (2024). Vitamin D modulates microbiome-dependent cancer immunity. Science. DOI: 10.1126/science.adh7954
