Vitamin D Found to Boost Immune System

Vitamin D’s benefits have been widely publicized, but its status as some sort of super vitamin is still up for debate. Now, in a new study by Dana-Farber researchers, vitamin D was found to boost the immune system and may even help protect the body against certain cancers.

Just last week, Dana-Farber announced that scientists there found in a different study that some patients who had high levels of vitamin D in their blood survived longer than those who didn’t.

“Clinical trial patients with metastatic colorectal cancer who had high levels of vitamin D in their bloodstream prior to treatment with chemotherapy and targeted drugs, survived longer, on average, than patients with lower levels of the vitamin,” the report said.

In this new study, which was published Thursday the journal Gut, researchers found a link between vitamin D and what the immune response is to cancer. It’s the first study of its kind because it was conducted on a large human population, and it supports ongoing research that vitamin D may play a large role in cancer prevention.

“People with high levels of vitamin D in their bloodstream have a lower overall risk of developing colorectal cancer,” said Dana-Farber’s Shuji Ogino, MD, and the study’s senior author. “Laboratory research suggests that vitamin D boosts immune system function by activating T cells that recognize and attack cancer cells. In this study, we wanted to determine if these two phenomena are related. Does vitamin D’s role in the immune system account for the lower rates of colorectal cancer in people with high circulating levels of the vitamin?”

According to the study:

To determine if this is indeed the case, the research team drew on data from 170,000 participants in the Nurses’ Health Study and Health Professionals Follow-up Study, two long-term health-tracking research projects. Within this population, researchers compared carefully selected groups of 318 colorectal cancer patients and 624 individuals who were free of cancer. All 942 of them had blood samples drawn in the 1990s, before any developed cancer. The investigators tested these samples for 25-hydroxyvitamin D, (abbreviated 25(OH)D), a substance produced in the liver from vitamin D.

They found that patients with high amounts of 25(OH)D indeed had a lower-than-average risk of developing colorectal tumors that were enriched with immune system cells.

“This is the first study to show evidence of the effect of vitamin D on anti-cancer immune function in actual patients, and vindicates basic laboratory discoveries that vitamin D can interact with the immune system to raise the body’s defenses against cancer,” Ogino said in a statement. “In the future, we may be able to predict how increasing an individual’s vitamin D intake and immune function can reduce his or her risk of colorectal cancer.”