Taking supplements of B vitamins and omega-3 fatty acids for cancer prevention does not appear to be beneficial for patients with prior cardiovascular disease. Proper nutrition is considered to be protective against cancer but much is unknown about the roles of individual nutrients in different populations.
Valentina A. Andreeva, Ph.D., of the University of Paris XIII, and colleagues performed secondary analyses of data from the Supplementation with Folate, Vitamins B6 and B12 and /or Omega-3 Fatty Acids (SU.FOL.OM3) Randomized Controlled Trial conducted in France from February 2003 to July 2009. Individuals between the ages of 45 to 80 who had an acute myocardial infarction (heart attack), unstable angina or ischemic stroke during the previous 12 months were eligible. In all, 2,501 patients (514 women and 1,987 men) were randomized in the trial.
In total, 174 participants (7 percent) presented with incident primary cancer. Of them, 145 occurred in men and 29 in women. Death from cancer occurred in 2.3 percent of the patients. There was no association between cancer outcomes and supplementation with B vitamins, omega-3 fatty acids or both.
“These ancillary results from the SU.FOL.OM3 trial do not provide evidence of beneficial effects of supplementation with B vitamins and/or ?-3 fatty acids in relatively low doses for five years on cancer incidence or mortality among CVD [cardiovascular disease] survivors,” the researchers comment.
They note that 83.3 percent of the cancer incidence and 81 percent of the cancer mortality occurred in men, who accounted for 79.4 percent of the sample, but neither type of supplementation produced any effects. Among women (about 83 percent of them were menopausal), both types of supplementation had a tendency to increase cancer risk, “however these results were derived from very few cases and should be regarded as preliminary,” researchers write.
“In summary, this study does not support dietary use of B vitamins or ?-3fatty acids for cancer prevention. The preliminary evidence of adverse effects among women necessitates confirmation before firm conclusions could be drawn,” the researchers conclude.
Source: Archives of Internal Medicine, USA