Vitamin D May Vanquish Colon Cancer

Vitamin D in the bloodstream in high levels may protect against colon cancer

(RxWiki News) Mom's advice to take your vitamins could be right on target. Vitamin D — the “sunshine vitamin” — might help prevent colon cancer.

A new study found that people who had high levels of vitamin D in their blood were less likely to develop one type of colon cancer than those with lower levels. Past research has found that vitamin D played a role in bolstering the immune system.

This is the first study to make a direct connection between vitamin D and colon cancer.

"People with high levels of vitamin D in their bloodstream have a lower overall risk of developing colorectal cancer," said lead study author Shuji Ogino, MD, PhD, of the Dana-Farber Cancer Institute, Harvard School of Public Health and Brigham and Women's Hospital in Boston, in a press release.

Dr. Ogino added that "Laboratory research suggests that vitamin D boosts immune system function by activating T cells that recognize and attack cancer cells. 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."

Dr. Ogino’s comments referred to past research that found that vitamin D may boost the immune system. T cells are specialized white blood cells in the body that help destroy cancer cells. Vitamin D activates these T cells.

Higher levels of vitamin D may mean the immune system is stronger. Dr. Ogino's team theorized that people with higher levels of vitamin D would be less susceptible to developing colon cancer because of this protective effect.

Dr. Ogino and team drew their data from two large studies — the Nurses' Health Study and the Health Professionals Follow-Up Study — that included more than 170,000 people.

These researchers compared vitamin D blood levels in nearly 1,000 patients, 318 of whom had developed colon cancer. Vitamin D levels were determined many years before the cancers developed.

Dr. Ogino and colleagues looked for a substance called 25-hydroxyvitamin D, abbreviated as 25(OH)D), which is produced from vitamin D in the human liver. They found that those patients who had higher 25(OH)D levels had a lower risk of developing colon cancer with high levels of 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," Dr. Ogino said.

Dr. Ogino and team did not suggest that patients take vitamin D supplements. Most people can produce vitamin D in their bodies through sunlight exposure. Patients with a family history of colon cancer or who think their vitamin D levels might be low should speak to their doctor.  Sunshine is free, but if your doctor recommends Vitamin D supplements, they are readily available OTC at most pharmacies, costing pennies per day.

This study was published Jan. 15 in the journal Gut.

The National Institutes of Health, the Friends of Dana-Farber Cancer Institute, the Bennett Family Fund, the Entertainment Industry Foundation, and the Paula and Russell Agrusa Fund for Colorectal Cancer Research funded this study.

Study author Dr. Andrew T. Chan had previously served as a consultant for Bayer Healthcare, Millennium Pharmaceuticals and Pfizer Inc. None of those organizations funded the current study.

Review Date: 
January 16, 2015