Reprinted with the kind permission of Life Extension.
May 23 2016. The May 14, 2016 issue of the World Journal of Gastroenterology published the results of a systematic review and meta-analysis of randomized trials that indicate a protective effect for calcium supplementation against the risk of colorectal adenoma, a precursor of colorectal cancer.
European researchers selected four trials that compared the effects of 1,200 to 2,000 milligrams elemental calcium per day to a placebo against the risk of colorectal adenoma during up to 60 months of treatment and follow-up. Subjects included men and women with resected colorectal cancer or those who had colorectal adenomas surgically removed prior to enrollment. Colonoscopic examinations conducted over the follow-up periods ascertained colorectal adenoma recurrence.
All of the trials reported a lower incidence of colorectal adenomas in the calcium group. The meta-analysis determined that subjects who received calcium experienced a 10% to 15% lower risk of adenoma recurrence compared with those who received the placebos.
The authors note that calcium may protect against colorectal neoplasia by binding bile and fatty acids, which reduces their carcinogenic effects on colon epithelial cells. Additionally, the mineral has a direct antiproliferative effect on cells and promotes cellular differentiation and apoptosis (programmed cell death).
Authors Stefanos Bonovas, MD, MSc, PhD and colleagues announce that the current study is the most up to date on the subject and that further clinical studies will help identify populations for whom calcium supplementation might be particularly beneficial for adenoma and cancer prevention.
“The magnitude of the colorectal cancer problem, and the failure of advanced disease chemotherapy to effect significant reductions in the respective mortality rates, indicate that an intensive approach to the prevention of this disease is necessary,” they observe. “These findings extend the results of the primary trials and have important implications for future research.”