High omega-3 levels could increase prostate cancer risk, study finds


by KING 5 News


Posted on April 25, 2011 at 11:17 AM

Updated Friday, Jan 4 at 10:44 AM

SEATTLE – Men who have a high percentage of omega-3 fatty acids may face an increased risk of aggressive prostate cancer, according to a new study from the Fred Hutchinson Cancer Research Center.

In a nationwide study of 3,400 men, researchers found that men with the highest blood percentages of an omega 3-fatty acid called docosahexaenoic acid, or DHA, had 2.5 times the risk of developing aggressive, high-grade prostate cancer compared to men with the lowest levels of DHA.

Omega-3 is commonly found in fatty fish and over-the-counter fish oil supplements, and used to reduce the risk of heart disease.

On the flip side, men with high amounts of trans-fatty acids, which are linked to heart disease, experienced only half the risk of high-grade prostate cancer.

"We were stunned to see these results and we spent a lot of time making sure the analyses were correct," said Dr. Theodore M. Brasky in a press release. Basky is a postdoctoral research fellow in the Hutchinson Center's Cancer Prevention Program.

Omega-6 fatty acids, which are also lined to inflammation and heart disease, were not associated with prostate cancer risk.

Despite the findings, Brasky and his colleagues say they don’t believe men should stay away from fish oil supplements or grilled salmon in an effort to reduce the risk of aggressive prostate cancer.

"Overall, the beneficial effects of eating fish to prevent heart disease outweigh any harm related to prostate cancer risk," Brasky said. "What this study shows is the complexity of nutrition and its impact on disease risk, and that we should study such associations rigorously rather than make assumptions.”

The findings are published in the American Journal of Epidemiology.