Do fish oil supplements really increase prostate cancer risk?

Fish oil supplements have been shown to provide a variety of benefits when it comes to cardiovascular health, but is there a down side to taking them?

We recently received this question from a viewer:

Dear Dr. Manny,
I heard taking fish oil can cause prostate cancer. Is this true?

The omega-3 fatty acids found in some fish are known to help reduce inflammation, and can be very beneficial in protecting against certain conditions like heart disease and even Alzheimer’s.

But a recent study in the Journal of the National Cancer Institute found a higher risk of prostate cancer among men who consumed omega-3 fatty acids. Those who consumed large amounts of EPA, DPA and DHA – compounds found in fatty fish and fish oil supplements – were 43 percent more likely to develop the disease.

While the results of the study may seem shocking, you may not need to throw out your supplements just yet.

Another study found that prostate cancer patients who ate a low-fat diet and took fish oil supplements slowed the progression of their disease and reduced their chances of recurrence.

With so many conflicting studies, it’s difficult to sort out the facts.

“While a recent study did demonstrate a correlation between elevated blood levels of omega-3 fatty acids – the chief ingredient in fish oil supplements – and prostate cancer, whether this is simply a correlation or a true cause-and-effect relationship is yet to be determined,” Dr. Scott David, an assistant professor of urology at Weill Cornell Medical College and New York – Presbyterian Hospital told“What’s also unknown is whether the type of fish oil consumed has an impact.”

When his patients ask him about omega-3 fatty acids, David said, he usually looks at their individual risk for developing prostate cancer.

Some risk factors for prostate cancer can include:

-Ethnic background
-Family history of prostate or breast cancer

“For those men with an increased risk of prostate cancer, it may be wise to reduce dietary fish oil until more data is collected,” David said.

It’s important to remember you should always talk to your doctor before making any changes to your diet or lifestyle.

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