Healthy Note: Fish oil and prostate cancer risk
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Taking fish-oil supplements or even eating too much fatty fish may be linked to an increased risk for prostate cancer, according to a new study from the Fred Hutchinson Cancer Research Center in Seattle.
The result confirms findings from an earlier study by the same team, but they are puzzling, given fish oil’s supposed anti-inflammatory effect, which would protect against cancer.
Researchers could not offer a biological reason for the link, and called for more study.
The study analyzed levels of omega-3 fatty acids — the type of oil found in some fish — in the blood of 834 men who developed prostate cancer race- and age-matched with 1,393 men who did not. Men who had the highest levels of omega-3 fatty acids had a 43 percent increase in risk for prostate cancer and 71 percent increase in risk for the high-grade prostate cancer that is the most likely to be fatal.
These results were published online Wednesday by the Journal of the National Cancer Institute.
The newest data come from a study whose initial goal, when it began in 2001, was investigating the roles of selenium and vitamin E in prostate cancer.
Prostate cancers can lie dormant for decades, and the risk factors for developing a tumor may not be the same as those that cause a tumor to become fatal.