A new benefit of vitamin D in cancer treatment has been discovered. The vitamin, which has been observed to strengthen a type of intestinal flora, leads to a better response to immunotherapy.
Previous studies have linked vitamin D to the prevention and treatment of various cancers. The new research has identified its role in immunotherapy, a treatment that uses the immune system to help the body defeat cancer.
In the study, researchers fed mice a diet rich in vitamin D and observed that the animals’ immune systems were better able to resist cancer and respond better to immunotherapy.
The scientists noted that this happens because vitamin D increases the amount of bacteria called Bacteroides fragilis in the gut. To understand the effect of this bacterium, which is also found in the human body, the team gave Bacteroides fragilis to mice receiving normal levels of vitamin D. These mice also showed better resistance to tumor growth.
On the other hand, Bacteroides fragilis given to mice on a vitamin D-poor diet did not produce the same effects.
“What we showed here was a surprise,” says Caetano Reis e Sousa, co-author of the study published April 25 in the peer-reviewed journal Science: Vitamin D can regulate gut flora, favoring a type of bacteria that makes mice better immune to cancer,” says Caetano Reis e Sousa, one of the authors of the study published in Science in April.
This may one day be important for cancer treatment in humans, but we don’t know how and why vitamin D exerts this effect through the microbiome. More studies are needed before we can say with certainty that correcting vitamin D deficiency benefits cancer prevention or treatment.
Dr. Anton Bilchik, a surgical oncologist at Saint John’s Cancer Institute in the US, says that the role of vitamin D in the fight against cancer is well known, but the new research is important in revealing the mechanism. Bilchik, who was not involved in the study, adds:
More importantly, it shows that immunotherapy may be more effective in combination with vitamin D. So these are completely newly identified mechanisms.
Bilchik also warns that vitamin D levels should not fall below normal, even if it may reduce the risk of cancer. Speaking to Medical News Today, he emphasizes the role this vitamin plays in reducing the risk of osteoporosis.
