While most of the news about Omega-3 is positive, a while ago I noticed a negative article – “Omega-3s are good for the heart, but not the prostate” (Globe & Mail, April 29, 2011). The article reports the results of a study out of Seattle involving 19,000 men over the age of 55. While the main aim of the study was to assess the drug finasteride (Proscar) and its effect on prostate cancer, the study also took regular blood tests from the participants. The analysis revealed that the men with the highest levels of DHA were 2.5 times more likely to develop aggressive prostate cancer. Surprisingly, the risk was 50% lower in men with high levels of (unhealthy) trans fat.
The study was published in the American Journal of Epidemiology. The article suggests that because the risk of dying from heart disease is very much higher than aggressive prostate cancer, a focus on increasing Omega-3 intake is still sensible. Heart disease is one of the leading causes of death in Canadian men, accounting for 22% of deaths annually.
As a further comment, it is very difficult to draw a meaningful conclusion from the results of this study without also knowing the EPA to DHA ratio in the blood samples (or ALA to DHA for that matter). The link below to the article in “marksdailyapple.com” raises further issues with the results of the study. As a further note, a later Globe & Mail article (see link below) suggests that finasteride itself may raise the risk of aggressive prostate cancer, and thus there may be an increased risk due to an interaction between finasteride and high DHA levels as well. However, the study does suggest that, while DHA is an essential fatty acid, an imbalance of too much DHA may lead to other health problems.
- Is Fish Oil Linked to Prostate Cancer? (marksdailyapple.com)
- Prostate drugs such as Proscar raise risk of high-grade cancer (theglobeandmail.com)
- Omega-3 fats hold the key to curing depression in the elderly (talesfromthelou.wordpress.com)