Controversial Study Links Omega 3 Fatty Acids and Prostate Health Risk

Courtesy of Lee Swanson Research

July 15, 2013

The Mediterranean diet has long been held up as a model for healthy eating, which is why a recent study linking high blood levels of omega 3 fatty acids with an increased risk of prostate cancer made headlines around the world. The study,¹ published in the Journal of the National Cancer Institute (JNCI), examined the plasma lipid levels of 834 men diagnosed with prostate cancer compared with 1,393 control subjects.

Compared with men with the lowest omega 3 fatty acid levels, men with the highest levels had an increased risk for low-grade and total prostate cancer. Omega 3s linked to prostate cancer? At first blush, this would appear to be alarming news; but as the old maxim goes, correlation does not equal causation. To make an informed decision, it’s important to look past the hype and the headlines and put things in perspective.
The controversial study measured levels of omega 3 fatty acids in plasma; it didn’t measure omega 3 intake, either through diet or supplementation. But this study wasn’t produced in a vacuum. There have been numerous studies throughout the past two decades examining omega 3 fatty acid consumption and its relationship with various diseases and health conditions. Many of these studies have found no link between omega-3 fatty acid consumption and the risk of prostate cancer,² and some have found consumption of fish to be associated with a decreased risk of prostate cancer.^3-5

Given the huge body of research indicating either no effect or a protective effect for omega 3 fatty acid consumption and prostate cancer risk, what are we to make of the findings in the JNCI study? It really comes down to a question of cause and effect. The evidence we have indicates that omega 3 consumption is not the culprit. It may be possible that patients with prostate cancer have altered lipid metabolism that causes elevated plasma omega 3 fatty acid levels. Future research may give us the answer to this biological puzzle.

1. J Natl Cancer Inst. 2013, July 10. doi: 10.1093/jnci/djt174 
2. Am J Clin Nutr. 2010 Nov;92(5):1223-33. doi: 10.1136/bmj.f3706
3. Cancer Epidemiol Biomarkers Prev. 2003 Jan;12(1)):64-7. Retrieved 15 July, 2013 from http://www.ncbi.nlm.nih.gov/pubmed/12540506
4. Am J Clin Nutr. 2004 Jul;80(1):204-16. Retrieved 15 July, 2013 from http://www.ncbi.nlm.nih.gov/pubmed/15213050
5. Lancet. 2001 Jun 2;357(9270): 1764-6. doi:10.1016/S0140-6736(00)04889-3