Vitamin B & Cancer

According to results published in this week’s Journal of the American Medical Association, a daily supplementation of B vitamins may reduce the risk of breast cancer and other cancers in women 65 and over.* Over 5,000 women at a high risk of cardiovascular disease took part in the study, which investigated the effects of a daily supplement of folic acid, vitamin B6 and B12 on cancer risk. Folate, vitamin B6, and vitamin B12 are thought to play an important role in cancer prevention. These vitamins play an important role in maintaining the integrity of DNA and regulating gene expression, both critical processes in healthy cell function.

Author Shumin Zhang, from Brigham and Women’s Hospital and Harvard Medical School, looked at the risk of cancer and B-vitamin consumption for the 5,442 participants, with an average age 62.8. The women either had cardiovascular disease or three or more coronary risk factors. Over the course of 7.3 years, half of the women received a daily supplement of folic acid (2.5 mg), vitamin B6 (50 mg), and vitamin B12 (1 mg), while the other half of the women received a placebo. During the study, 379 cases of invasive cancer were diagnosed – 187 in the B-vitamin group and 192 in the placebo group. There were no differences in the risk of developing total invasive cancer or breast cancer when the participants were viewed as a whole. However, in women over the age of 65 the supplementation was associated with significant 25% and 38% reductions in the risk of invasive cancer and breast cancer, respectively.

* S. M. Zhang, N.R. Cook, C.M. Albert, J.M. Gaziano, J.E. Buring, J.E. Manson. ” Effect of Combined Folic Acid, Vitamin B6, and Vitamin B12 on Cancer Risk in Women.” Journal of the American Medical Association November 4, 2008, Volume 300, Issue 17, Pages 2012-2021.