Study on Vitamin D and Cancer Rates Raises Confusion

A study from Creighton University which examined the ability of Vitamin D supplements to reduce the risk of cancer did not reach a decisive conclusion, continuing an ongoing controversy on the subject.

The study, which was published in the Journal of the American Medical Association, examined 2,300 women past the stage of menopause and gave them either a Vitamin D supplement or a placebo over a four-year period. At the end of the test, the study found that the supplementation “did not result in a significantly lower risk of cancer among healthy older women.”

The study’s researchers, led by Dr. Joan Lappe, did state that this test was not a decisive conclusion. Cancer rates were higher in the placebo group, if not significantly so, and four years is not very long for a study like this. Furthermore, many of the woman in the placebo were taking Vitamin D supplements outside of the test for its other health effects such as stronger bones.

Vitamin D’s Effects

The ability of Vitamin D to help battle cancer, even extreme cases like mesothelioma, has long been a contentious affair. The National Cancer Institute states that research into the links between Vitamin D and cancer began when researchers noted that humans living in sunnier southern latitudes were less likely to receive and die from cancer compared to those living in northern latitudes. But while numerous studies have been carried out to examine a link, “the results of these studies have been inconsistent, possibly because of the challenges in carrying out such studies.”

For example, a person who is outside and active will receive more Vitamin D from sunlight than one who stays indoors all the time. But while the first person is less likely to get cancer, is it because he received more Vitamin D or because of the general benefits of exercise? Conducting a study which can remove these outside factors is a challenge for any study, including this most recent one.

While more research needs to be done, the test was not a victory for the idea that Vitamin D can help fight cancer. But that did not stop certain websites from looking at the study and declaring that “Vitamin D decreases risk of cancer, new study suggests.”

Khuram Aziz
Khurram Aziz is a freelance writer based out of London, England.