A Prospective Study of Intake of Fish and Marine Fatty Acids and Prostate Cancer

A Prospective Study of Intake of Fish and Marine Fatty Acids and Prostate Cancer1

Departments of Nutrition [K. A., D. S. M., E. B. R., M. F. L., M. J. S., W. C. W., E. G.] and Epidemiology [E. B. R., M. J. S., W. C. W., E. G.], Harvard School of Public Health, and Channing Laboratory, Department of Medicine, Harvard Medical School and Brigham and Women’s Hospital [E. B. R., M. J. S., W. C. W.], Boston, Massachusetts; Department of Medical Epidemiology, Karolinska Institutet, SE-171 77 Stockholm, Sweden [K. A.]; and Nutritional Epidemiology Branch, National Cancer Institute, Bethesda, Maryland [D. S. M., M. F. L.]

Abstract

Experimental studies suggest that marine fatty acids have an antitumor effect on prostate tumor cells. The aim of this study was to investigate whether high consumption of fish and marine fatty acids reduces the risk of prostate cancer in humans. We followed 47,882 men participating in the Health Professionals Follow-up Study. Dietary intake was assessed in 1986, 1990, and 1994, using a validated food frequency questionnaire. During 12 years of follow-up, 2,482 cases of prostate cancer were diagnosed, of which 617 were diagnosed as advanced prostate cancer including 278 metastatic prostate cancers. Eating fish more than three times per week was associated with a reduced risk of prostate cancer, and the strongest association was for metastatic cancer (multivariate relative risk, 0.56; 95% confidence interval, 0.37–0.86, compared with infrequent consumption, i.e., less than twice per month). Intake of marine fatty acids from food showed a similar but weaker association. Each additional daily intake of 0.5 g of marine fatty acid from food was associated with a 24% decreased risk of metastatic cancer. We found that men with high consumption of fish had a lower risk of prostate cancer, especially for metastatic cancer. Marine fatty acids may account for part of the effect, but other factors in fish may also play a role.

Footnotes

The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked advertisement in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.
↵1 Supported by USPHS Grant CA 55075 from the National Cancer Institute; USPHS Grant HL 35464 from the National Heart, Lung and Blood Institute; the Swedish Cancer Society; and the Foundation Blanceflor Boncampagni-Ludovisi, nee Bildt.
↵2 To whom requests for reprints should be addressed, at Department of Medical Epidemiology, Karolinska Institutet, SE-171 77 Stockholm, Sweden. Phone: 46-8-7286821; Fax: 46-8-314957; E-mail: katarina.augustsson{at}mep.ki.se
↵3 The abbreviations used are: EPA, eicosapentaenoic acid; DHA, docosahexaenoic acid; PSA, prostate-specific antigen; CI, confidence interval.
- Accepted November 8, 1902.
- Received December 31, 1901.
- Revision received October 28, 1902.