Men who consume moderate to high amounts of fatty fish such as salmon, herring and mackerel, which contain high levels of omega-3 fatty acids appear to have a significantly reduced risk of prostate cancer.
Swedish researchers collected data from 6272 male twin pairs with a mean age of 55.6 years in 1967. The subjects completed questionnaires on lifestyle factors, including diet, smoking and exercise. During up to 30 years of follow up, there were 466 cases of prostate cancer among these men.
When the team looked at the association between prostate cancer and fish consumption, they found that a high fish consumption was associated with physical activity, smoking, and consumption of fruits and vegetables, but not with eating red and processed meat.
Analysis of the data revealed that an increased fish consumption was associated with a decreased risk of prostate cancer. Those men who did not eat fish had a two to threefold greater risk of developing prostate cancer compared with men who ate moderate to high quantities of fatty fish (Lancet, 2001; 357: 1765-6).