B-vitamins and fish oil do not appear to offer protection against cancer. A study of more than 2,500 French people compared the supplements to placebo for five years. The investigators found that the mixture of vitamin B6, folic acid and vitamin B12 was no better than a sugar pill for preventing cancer.
Men who took 600 mg a day of omega 3 fats were neither more nor less likely to get cancer as those on placebo. But women taking fish oil had triple the number of cancers. The scientists admit that the study does not establish cause and effect. The findings contradict those from a recent observational study that found fish oil was linked to a lower risk of breast cancer in women.
[Archives of Internal Medicine, Feb. 13., 2012]