Vitamin D intake can prevent the common side effect of anti-cancer immunotherapy

This is the first study to report that among patients treated with ICIs, vitamin D intake is associated with reduced risk for ICI colitis.


Vitamin D is essential for several reasons, including maintaining healthy bones and teeth. It may also protect against a range of diseases and conditions, such as type 1 diabetes.

Now, a new study has added one more benefit to the list. According to the study published early online in CANCER, taking vitamin D supplements may help prevent a potentially severe side effect of a revolutionary form of anti-cancer therapy.

Osama Rahma, MD, of the Dana-Farber Cancer Institute and Harvard Medical School, in Boston conducted a study along with his colleagues. They examined whether taking vitamin D supplements might reduce the risk of colitis in patients receiving immune checkpoint inhibitors to treat their cancer.

The study included information on 213 patients with melanoma who received immune checkpoint inhibitors between 2011 and 2017. Thirty-seven (17 percent) of these patients developed colitis. Sixty-six patients in the study (31 percent) took vitamin D supplements before starting treatment with immune checkpoint inhibitors.

Scientists found that patients who took vitamin D had 65 percent lower odds of developing colitis, after adjustments for confounding factors. These findings were validated in another group of 169 patients, of whom 49 (29 percent) developed colitis. In this validation group, the use of vitamin D was linked with 54 percent lower odds of developing colitis.

Immune checkpoint inhibitors help the immune system recognize and combat cancer cells. Although these treatments have helped many patients and have prolonged lives, they can cause side effects such as colitis, an inflammatory reaction in the colon.

Dr. Rahma said, “Immune checkpoint inhibitor-induced colitis can limit the use of such life-saving drugs leading to discontinuation of treatment. While it is one of the most common and severe adverse events of immunotherapy, there is a lack of understanding of the risk factors that could be modified to prevent colitis.”

“Our findings of a link between vitamin D intake and reduced risk for colitis could potentially impact practice if validated in future prospective studies. Vitamin D supplementation should be tested further to determine if it could be a safe, easily accessible, and cost-effective approach towards preventing immunotherapy’s gastrointestinal toxicity and extending the effectiveness of immune checkpoint inhibitor treatment in cancer patients.”

Journal Reference:
  1. Shilpa Grover MD, MPH et al. Vitamin D intake is associated with decreased risk of immune checkpoint inhibitor‐induced colitis. CANCER. DOI: 10.1002/cncr.32966