Vitamin D May Help Prevent - and Treat - Colorectal Cancer
You may already know that a daily dose of sunlight - necessary to create vitamin D - can ward of depression and improve your body’s circadian rhythm. But did you know that it may also help in the fight against cancer?
Researchers from the Dana-Farber Cancer Institute have shown that vitamin D can help to boost the immune system, helping the body to fight colorectal cancer. Their study adds to a growing body of knowledge about how the immune system responds to cancer cells.
Colorectal cancer is the third most common cancer and the second leading cause of cancer deaths in the US. The Centers for Disease Control and Prevention (CDC) found that 51,783 people died from the disease in 2011, the most recent year for which statistics are available.
Inside the human body, vitamin D assists the immune system and contributes to calcium absorption and the growth and repair of bones. Previous research has shown that vitamin D plays a role in preventing cancer, but the new research is the first to show that it can help to fight existing cancers. This is just one of the many benefits of vitamin D, which has also been shown to reduce the risk of multiple sclerosis, asthma attacks and heart attacks.
"People with high levels of vitamin D in their bloodstream have a lower overall risk of developing colorectal cancer," says senior author Dr. Shuji Ogino. "Laboratory research suggests that vitamin D boosts immune system function by activating T cells that recognize and attack cancer cells."
The study aimed to find whether vitamin D’s role in the immune system accounted for the lower rates of colorectal cancer in people with high levels of vitamin D.
The researchers assessed data from 942 partipants drawn from long-term research studies. 318 had colorectal cancer and 624 were cancer-free. Each participant had had a blood sample taken sometime in the 1990s, before any of the participants developed cancer. These samples were tested for a substance produced by vitamin D in the liver.
Participants with high amounts of the substance - named 25-hydroxyvitamin D - were found to be less likely to develop colorectal cancer, suggesting that the researchers were correct in connecting high levels of circulating vitamin D to a decrease in colorectal cancer incidence.
"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," states Dr. Ogino.