A recently published paper is gaining a lot of attention this past month in both medical circles and the mainstream media because in it, the authors state that this “confirms previous reports [by same research team] of increased risk of prostate cancer risk among men with high blood concentrations of long chain omega 3 polyunsaturated fatty acids.” The authors suggest “that these fatty acids are involved in prostate tumorigenesis.”
Some leading researchers on omega 3 fatty acids are criticizing these conclusions. They point out that the difference in omega 3 fatty acid levels between non-cancer, total cancer, low grade cancer and aggressive cancer groups were 3.62%, 3.66%, 3.67% and 3.74% respectively, which they emphasize are very small and within the normal variation. Some suggest that the authors of the study are extrapolating beyond the data.
They also point out that the study does not look at the source of the omega 3 fatty acids. Some critics of the conclusion that omega 3s are linked to prostate cancer state that it is possible that some component in the fish these men were consuming may be carcinogenic. The study does not state whether the increased omega 3 fatty acids levels in the blood were due to supplements or fish intake, and they emphasize that association does not imply causation.
Finally, many scientists are pointing to an abundance of other studies that conclude omega 3 fatty acids lower prostate cancer risk, stating also that epidemiological evidence of high fish consumption countries tend to have lower prostate cancer rates.
(Journal of the National Cancer Institute, July 2013)
(American Journal of Clinical Nutrition, 2010 and 2004)
LINK to ABSTRACT Dietary intake of n-3 and n-6 fatty acids and the risk of prostate cancer.