Vitamin D and Bowel Cancer

Vitamin D is normally produced by the skin when it gets in touch with sunlight. It can also be obtained from various diets such as fatty fish and fortified foods where it’s absorbed into the bloodstream from our guts.

The main purpose of this vitamin has been to maintain bones but as research on it broadens, it has been established that its role is not limited just to the bones.

So far, studies have successfully linked the vitamin with obesity, cardiovascular disease and Parkinson’s, among other many conditions.

Its influence on the progression of cancer has also been investigated.

Vitamin D and Colorectal Cancer

Joint researchers from the Harvard T.H. Chan School of Public Health in Boston, the American Cancer Society (ACS) in Atlanta and the United States National Cancer Institute in Rockville, came together to study the manner in which Vitamin D impacts one’s risk to colorectal cancer.

Also referred to as bowel cancer, colorectal cancer is among the most common type of cancer in the United States besides skin cancers. It is estimated that cancer claims more than 50,000 lives on a yearly basis.

Thus, it is important to learn about the different factors that play a role in its development. If there is a chance that Vitamin D is involved, it opens new avenues for developing preventive and treatment options.

Previous studies seem to disagree on whether Vitamin D is involved with some suggesting that it is involved while others disputing this claim. That is why a large-scale study was planned to get a clear picture on the matter.

The study’s research findings were published in the Journal of the National Cancer Institute.

How the Study was done

As explained by Co-senior study author Stephanie Smith-Warner, the researchers gathered data on diagnoses before colorectal cancer from 17 prospective cohorts. They then made use of the standardization criteria across all past studies on the matter.

The team picked data from studies done on three different continents, which comprised of 7,100 controls and 5,700 colorectal cancer cases.

Past studies had a challenge with pooling data from various studies due to the diverse ways for measuring Vitamin D. To solve this problem, existing measurements were calibrated to ensure direct comparisons can be made in a meaningful way with respect to the various trials.

The Vitamin D levels of each person were compared with what the National Academy of Medicine recommends as a requirement for healthy bones.

It was found that those whose Vitamin D levels were lower than the set standards had a 31% increased risk of developing colorectal cancer. Individuals who were above the recommended Vitamin D standards benefited from a 22% reduction in risk of developing this type of cancer. Women showed stronger links than the men.

Even after adjusting the data to factor in other issues, the team was still able to note a significant relationship.

This study has added value to the evidence that vitamin D could be used to protect individuals from bowel cancer.