Is There Something Fishy About Fish Oil and Your Prostate?

Fish oil supplements hold center stage in the theater of disease prevention. Fish is high in omega-3 fatty acids—essential nutrients for heart health. Humans cannot produce omega-3 fatty acids, so it’s important to get them from an external source. The American Heart Association (AHA) recommends eating fish at least twice per week. Not just any fish, but the fatty types that are high in omega-3 such as salmon, mackerel, herring, lake trout, sardines and albacore tuna. Eating fish optimizes omega-3 absorption. The AHA says, “Increasing omega-3 fatty acid consumption through foods is preferable.”

If you don’t like fish…

Of course, not everyone is wild about fish. In this case, they may consider taking fish oil supplements. You might be amazed to learn the variety of conditions for which people take capsules of fish oil. The most well-known include

  • Reduce triglycerides
  • Lower blood pressure
  • Lessen risk of heart attack and stroke
  • Slow down development of plaque in arteries
  • Reduce the chance of abnormal heart rhythm

Clearly, fish oil’s strong suit is promoting cardiovascular health. But there’s more. People also use fish oil for certain kidney ailments and kidney disease, eye problems like glaucoma and macular degeneration, gastrointestinal problems such as Crohn’s disease or inflammatory bowel syndrome, athletic performance improvement and muscle soreness after exercise, and many more conditions. With all those benefits, you may wonder, what about fish oil and prostate health?

What about the prostate gland?

In 2013, a paper published by Brasky, et al.[i] threatened to tarnish the good name of fish oil supplements.  Using data from the SELECT (Selenium and Vitamin E Cancer Prevention) Trial, the Brasky team found a correlation between higher blood levels of omega-3 fatty acids and greater risk of prostate cancer (PCa). In fact, they calculated a 44% higher risk of low-grade PCa and a 71% increased risk of high-grade PCa. This startling association was picked up by the media, creating confusion among doctors and their patients, especially men at risk of PCa or currently diagnosed with it.

Further clarification is needed

Papers published since the Brasky study question the message promoted by media. First, correlation does not necessarily mean cause-and-effect. Second, omega-3 fatty acids have 3 components: eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA), and docosahexaenoic acid (DHA); if analyzed separately, there seems to be a greater correlation with DHA than the other two.[ii] Many have pointed out that more research is needed on whether the source (eating fish vs. taking fish oil supplements) makes a difference. Others have demonstrated a lower risk of PCa among men with higher blood levels of omega-3 fatty acids.[iii] More research is needed to ultimately clarify whether fish oil supplements pose a PCa protection or hazard.

Back to where we started

With all the conflicting evidence, the burden of the fish oil supplement decision falls on the consumer. Recommendations abound, pointing in many directions. You will find demographic statistics, for instance, showing that Japanese intake of omega-3 fatty acids in their diet is about eight times that of U.S. men yet “…the Japanese prostate cancer rate of 22.7 per 100,000 in 2008 was dramatically lower than the U.S. rates of 83.8 per 100,000.”[iv]

Since the Japanese diet consists of considerably more fish, this brings us back to the AHA’s urge to eat more fatty fish. Since Mother Nature designed us to derive the greatest nutritional benefit from dietary sources, a general principle to follow is expressed in a blog from Harvard Health Publications:

… you should still consider eating fish and other seafood as a healthy strategy. If we could absolutely, positively say that the benefits of eating seafood comes entirely from omega-3 fats, then downing fish oil pills would be an alternative to eating fish. But it’s more than likely that you need the entire orchestra of fish fats, vitamins, minerals, and supporting molecules, rather than the lone notes of EPA and DHA.[v]

Fish is not the only source of omega-3 fatty acids. There are plant-based omega-3 fatty acids, but they are not exactly equivalent to those found in fish and fish oil. Vegetarians should consume flaxseed oil, chia seeds, walnuts and leafy greens—but keep in mind that it’s worth a consultation with a knowledgeable dietary specialist to assure a protective balance. If you only have one prostate, and you want to keep it in peak condition, stay informed so you make the wisest dietary choices.

NOTE: This content is solely for purposes of information and does not substitute for diagnostic or medical advice. Talk to your doctor if you have health concerns or questions of a personal medical nature.


[i] Brasky TM, Darke AK, Song X, Tangen CM, Goodman PJ et al. Plasma phospholipid fatty acids and prostate cancer risk in the SELECT trial. J Natl Cancer Inst. 2013 Aug 7;105(15):1132-41.

[ii] https://www.harvardprostateknowledge.org/high-intake-of-omega-3-fats-linked-to-increased-prostate-cancer-risk

[iii] Chavarro Jorge E., Stampfer Meir J., Li Haojie, Campos Hannia, Kurth Tobias, Ma Jing. A prospective study of polyunsaturated fatty acid levels in blood and prostate cancer risk. Cancer epidemiology, biomarkers & prevention: a publication of the American Association for Cancer Research, cosponsored by the American Society of Preventive Oncology. 2007;16:1364–1370.

[iv] Alexander W. Prostate Cancer Risk And Omega-3 Fatty Acid Intake From Fish Oil: A Closer Look at Media Messages Versus Research Findings. P T. 2013 Sep; 38(9): 561–564.

[v] https://www.harvardprostateknowledge.org/high-intake-of-omega-3-fats-linked-to-increased-prostate-cancer-risk