Researchers from several European medical centers affiliated with the EPCI study have reported that low vitamin D levels are associated with an increased risk of colorectal cancer. The details of this study were published January 21, 2010 in the British Medical Journal.
Colon cancer is the third most common cancer in the United States. A number of very good studies have shown that people with higher vitamin D levels can have as little as half the risk of developing colon cancer as those with lower vitamin D levels. One National Cancer Institute study of close to 17,000 people nationwide found that those with high vitamin D levels had an almost 75 percent lower risk of dying from colon cancer compared with those with low to moderates levels.
The EPIC study involves 520,000 participants from 10 western European countries. There were 1,248 cases of colorectal cancer diagnosed in this population. Vitamin D levels were measured in all participants. Low levels were defined as 75 nmol/l.
* Low levels of vitamin D were associated with a 32% increased risk of colorectal cancer.
* Vitamin D levels of 75-99 nmol/l were associated with a 12% reduced risk of colorectal cancer.
* Vitamin D levels >100 nmol/l were associated with a 23% reduced risk of colorectal cancer.
* The primary risk reduction at high vitamin D levels was for colon cancer and not for rectal cancer.
* Increased calcium intake was associated with a lower risk of colorectal cancer.
* Dietary vitamin D intake was not associated with risk of colorectal cancer.
These authors concluded: “The results of this large observational study indicate a strong inverse association between levels of pre-diagnostic 25-(OH)D concentration and risk of colorectal cancer in western European populations. Further randomised trials are needed to assess whether increases in circulating 25-(OH)D concentration can effectively decrease the risk of colorectal cancer.”
Comments: This study confirms previous observations. These findings also support the concept of providing supplementation to keep vitamin D levels above 100 nmol/l, even if the requisite randomized trials have not yet been performed.
 Jenab M, Bueno-de-Mesquita HB, Fettari P, et al. Association between pre-diagnostic circulating vitamin D concentration and risk of colorectal cancer in European populations: a nested case-control study. British Medical Journal. 2010;340:b5500.