US study raises alarm on omega-3


WASHINGTON—US scientists say they have confirmed a surprising 2011 study that found a higher risk of prostate cancer among men who consume omega-3 fatty acids, raising new questions about the safety of supplements.

The research in the Journal of the National Cancer Institute reported a 71 percent higher risk for dangerous high-grade prostate cancer among men who ate fatty fish or took fish-oil supplements, which are often touted for their anti-inflammatory properties.

“We’ve shown once again that use of nutritional supplements may be harmful,” said Alan Kristal, researcher at Fred Hutchinson Cancer Research Center and senior author of the paper.

Scientists are still puzzled as to why omega-3s appear linked to a greater risk of prostate cancer, but they said the findings suggested they were somehow involved in the formation of tumors.

The same team of researchers published similar findings in 2011, linking high blood concentrations of DHA to a more than double risk of high-grade prostate cancer, which is more likely to be fatal than other types.


Potential risks

A large European study also found the same omega-3 and prostate cancer link.

“The consistency of these findings suggests that these fatty acids are involved in prostate tumorigenesis and recommendations to increase long-chain omega-3 fatty acid intake, in particular through supplementation, should consider its potential risks,” the US study said.

The difference in blood concentrations of omega-3 fatty acids between the highest and lowest risk groups was about 2.5 percentage points (3.2 percent vs 5.7 percent), or just higher than the effect of eating salmon twice a week, Kristal said.


Controlled trial

The latest study was based on an analysis of specimens and data from a large randomized, controlled trial that tested whether selenium and vitamin E would reduce prostate cancer risk.

The trial, known as Select (the Selenium and Vitamin E Cancer Prevention Trial), found that vitamin E raised the prostate cancer risk and selenium showed no impact either way.

For the July 11 study in the Journal of the National Cancer Institute, researchers analyzed the data on 834 men diagnosed with prostate cancer and compared them to a random sample of 1,393 taken from the Select trial.

Increased risk

Those who had high blood concentrations of the fatty acids EPA, DPA and DHA were shown to have a 71 percent increased risk of high-grade prostate cancer.

The increased risk of low-grade prostate cancer was 44 percent higher in those with elevated fatty acid levels, and the combined risk was 43 percent for all prostate cancers.

Due to the nature of the study, it was not possible to tell for certain whether the elevated blood levels were due to men taking supplements or eating fish rich in omega-3s.

Benefits unclear

However, Franklin Lowe, associate director of the department of urology at St. Luke’s-Roosevelt Hospital in New York, said the findings should remind consumers that supplements may not help, and may even do harm.

“In general, there is nothing that has been proven to actually limit the risk of prostate cancer,” said Lowe, who was not involved in the study.

“For the most part, doctors do not recommend this stuff because it is unclear what the true benefits are for most of the supplements that people take.”

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  • Kowboy Santos

    “In general, there is nothing that has been proven to actually limit the risk of prostate cancer,” said Lowe, who was not involved in the study.””

  • Prangka

    Just when I started eating large quantity of fish, eat eggs fortified with Omega-3 and use canola oil for saute and deep fry. Then Boom.

  • mangpepe

    di pa ba kayo nalilito, pera pera lang walang personalan

  • nakatutok

    sana mabasa ito ng kilala kong tubero….OLD AGE PENSIONER na yun, baka inom ng inom ng supplements…

  • latino_boom

    What is good for the heart is bad for the prostate ganun ba yun ah hehehe…kakalito na buset …basta in moderation na lang

    • Prangka

      Ganito ang sagot dyan, ituloy ang supplement pero isama sa healthy regimen ang masturbation. 40% decrease din yan sa prostate cancer.:)

  • batangpaslit

    advertisement war:
    rice is bad since it is fattening
    salt is bad because it is hard on kidney
    sugar is bad because it causes diabetes
    kissing is bad because the mouth of the other partner have germs
    what shall we eat if rice is bad?
    how do we retain water in our body if we discard salt?
    where do we get our energy if sugar is absent in our blood system?
    what shall we do with our spouses, gf or bf if by holding hands or damping our lips against their lips, we will be contaminated with germs?

    • phthlateous

      do not worry pre’ they will find something to sell to us eventually.

      but first they will need to scare us, then when we are scared enough, that is when they will sell us the solution. marketing geniuses are all out there competing for the almighty dollar.

      “scare ‘em, then sell ‘em.” – ….works all the time ……”now is the best time to buy…”; “hurry, sale ends….”, “hurry, quantity is limited.”

      • batangpaslit

        Bro, saludo ako sa ‘yo. Nagawa mong mapatawa ako sa sa feedback mo eh…chuckles.
        Akalain mo, ang itlog at gatas ay bawal eh, natural food ang mga ‘yan?
        Ayos, banat mo ah.
        Ano ba tawag dian, satire?

  • JohnDoeGB

    Another proof that too much of something is bad enough.

    • foreignerph

      Correct. The study mentions food supplements, not the real stuff like fatty fish. Americans overdo everything and make their food supplements industry rich by it. Just have a moderate balanced diet of natural ingredients like fruits, veggies and a modest amount of non-fat proteins like fish, and you will stay healthy.

  • Karabkatab

    Take everything in moderation. Anything in excess is not good for us. But, we must be aware that it is improssible to always achieve a “balance diet” in our daily routine.

  • divictes

    Most canned tuna and sardines have DHA and Omega 3 proudly displayed on their labels, Will these cause havoc on their sales? Still nothing will keep me from my kinilaw__ bolinao, tulingan, or pating.

    • foreignerph

      The study mentioned excesses by artificial food supplements, not the real thing.

  • phthlateous

    lol, it has gone its 180 degree turn….now let’s wait for the other 180 degree turn to complete the 360 degrees.

    wait a while and then it’s gonna be good for you again.

    remember coffee…..started as good for you, then became bad for you (caused pancrea problems, etc.), then it became good for you again (against diabetes and now becomes an anti-oxidant) – a full 360 degrees. perhaps in time, it will still do a 720 degree turn ?

    • Karabkatab

      Agree. Everything in this new world of ours is influenced by commercialism and lobbying. Take the case of our local coconut oil. It was portrayed as an unhealthy oil for a long time by the media and world competitors. And look, who are often sick due to low immune system, the corn, soya oil users or the coconut oil users?

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