Omega-3 PUFA: good or bad for prostate cancer?

Introduction: The objective of this meta-analysis was to estimate quantitatively the associations between intake or status of omega-3 polyunsaturated (omega-3 PUFA) fatty acids and occurrence of prostate cancer in observational studies in humans. Methods: We combined risk estimates across studies using random-effects models. Results: The combined estimate showed an increased risk of prostate cancer in men with a high intake or blood level of α-linolenic acid (ALA) (combined relative risk (RR) 1.36; 95% CI 1.08-1.70). The association is stronger in the case-control studies (RR 1.84; 95% CI 1.04-3.25) than in the prospective studies (RR 1.10; 0.91-1.32). Ecosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) were not significantly associated with prostate cancer. Discussion: The association between high intake of ALA and prostate cancer is of concern and needs further study. However, the fact that the prospective studies do not show a clear association makes a true effect of intake of ALA on prostate cancer less likely. © 2008