Earlier research has found there is a 30% to 40% reduced risk of colon cancer in individuals consuming high dietary folate compared with those with low dietary folate. Building on these findings, researchers fed 57 mice a control diet containing 2 mg of folic acid per kg of body weight and fed 80 mice a “folate-deficient diet” that contained 0.3 mg of folic acid per kg of bodyweight for 12 to 14 months.
They found that none of the mice on the control diet had intestinal tumors. However, 25% of the mice (20 out of 80) on the folate-deficient diet had at least one tumor, with 13 mice having a single tumor, 4 mice having 2 tumors each and 3 mice having 3 tumors each.
When discussing these results, the researchers proposed that folic acid deficiency decreases activity of one of the most well known cancer-fighting enzymes in the body called p53. In the end, they concluded that “dietary folate deficiency can initiate tumors in the intestine.”
A daily multivitamin is a common source of supplemental folic acid.
Knock E. Low Dietary Folate Initiates Intestinal Tumors in Mice, with Altered Expression of G2-M Checkpoint Regulators Polo-Like Kinase 1 and Cell Division Cycle 25c. Cancer Res 2006 Nov; 66:10349-10356.