Omega-3 fatty acids have an anti-inflammatory effect and help protect against cardiovascular disease, studies show. However, new research has found that men with high blood levels of the omega-3 fatty acid DHA (docosahexaenoic acid) have a significantly higher risk of developing aggressive prostate cancer. For comparison, a 2007 study showed that – high intake of the omega-3 fatty acids DHA and EPA (eicosapentaenoic acid) can limit the risk of developing prostate cancer by 40%. The current study involved over 1,000 people and was conducted by the Fred Hutchinson Cancer Research Center in Seattle . Scientists are looking at the link between fatty acids in the blood and the spread of prostate cancer. The results showed that men with the highest DHA levels were 2.5 times more likely to develop aggressive prostate cancer than those with the lowest DHA levels. Another surprising finding was that men with the highest blood levels of trans-fatty acids, known to be harmful to the heart, had half the risk of cancer compared to those with the lowest levels. The study was published in the American Journal of Epidemiology.