Vitamin D Goes Beyond Bone Health: A Link To Colon Cancer?
Vitamin D is the darling of nutrition – it’s received the lion’s share of attention among the vitamins for its ever-growing list of health benefits beyond just supporting bone health. Studies have shown a compelling - yet still emerging - relationship between vitamin D and colon cancer. But what does the research say regarding vitamin D in patients who already have colon cancer?
Wesa and colleagues conducted a retrospective cohort trial where they analyzed samples from 250 patients with colorectal cancer. They wanted to determine whether the presence of vitamin D deficiency (defined as serum 25-hydroxyvitamin D levels below 30 ng/mL). When they compared the survival rates of these patients, having an adequate vitamin D status was associated with a more prolonged survival compared to having a deficient vitamin D status (HR = 0.61; p=0.041). It’s also worth noting that the majority (83%) of patients were found to be vitamin D deficient, with a median vitamin D status of 21 ng/mL. Of course, we have to remember that due to the nature of the study one can’t determine whether this is a cause-and-effect relationship, but it certainly is exciting to think that something as easily correctable as vitamin D deficiency plays a role in colorectal cancer mortality.
While these data are preliminary and presumably limited to a subset of people (i.e., patients with colorectal cancer), I believe there’s two points we can all take away from this. One, is that the health benefits of vitamin D extend well beyond bone health, and it’s exciting to see the ever expanding scope of vitamin D’s biology. If in fact future research does prove this to be a true causal relationship – that higher vitamin D status is associated with better overall survival in colorectal cancer patients – this holds a lot of promise for a very vulnerable group of people. Second, data like this underscores the need for greater screening of patients for nutrient status markers, and vitamin D would (in my opinion, anyway) be among those highest on the priority scale. I know some folks may disagree, but these disagreements are what keep science moving.
Wesa KM, Segal NH, Cronin AM, et al. Serum 25-hydroxyvitamin D and survivial in advanced colorectal cancer: a retrospective analysis. Nutr Cancer 2015; (epub ahead of print).
Klampfer L. Vitamin D and colon cancer. World J Gasterointest Oncol 2014; 6(11): 430-437