Many of my patients and readers have expressed concerns about recent news reports of definitive links between omega-3 fatty acids/fish oil and prostate cancer. This is an example of irresponsible journalism at its worst.
There is nothing definitive about this study and, in fact, warnings about the dangers of fish and fish oil fly in the face of the bulk of the research on this topic.
Fish Oil and Prostate Cancer Facts
This study, which was published in the July 11 online edition of the Journal of the National Cancer Institute, does not establish that elevated levels of long-chain omega-3s, found primarily in fish and fish oil, play a causative role in cancer.
This study only measured blood levels of omega-3s, not fish intake or supplement use.
Previous studies correlating blood levels of omega-3s with prostate cancer have had inconsistent results; whether the findings reported in this latest study will be repeated in future research is open to question.
There have been many previous epidemiological (population-based) studies linking fish oil and prostate cancer risk. They tend to show that fish consumption reduces prostate cancer risk, and they quite clearly indicate that frequent fish consumption reduces risk for prostate cancer mortality.
The only study that has attempted to correlate use of fish oil and prostate cancer risk—a study done by some of the same researchers who conducted this latest one—failed to observe any association in this regard.
Prostate cancer mortality has been notably low in the Japanese, a society in which fish consumption is traditionally quite high.
Fish has long been recognized as an exceptionally healthy dietary component, and thousands of studies support the benefits of supplemental fish oil. Epidemiology continues to confirm decreased cardiovascular risk in people who eat fish regularly, and there is good reason to suspect that fish oil supplements will reduce risk of cardiac death, especially in people not using statins. In addition, many studies have correlated good omega-3 status with reduced risk or rate of cognitive decline in older people.
Bottom line: While there is a wealth of research on the health benefits of omega-3 fatty acids, there is no clear link between omega-3s, or fish oil, and prostate cancer. Do not eliminate fish from your diet or throw out your fish oil supplements based on this one study and the news reports that jumped to unsubstantiated conclusions.
Now it's your turn: Do you take fish oil?
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