Regular readers of this column (love ya!) know what big fans we are of omega-3s. (Dr. Mike may like them as much as his beloved Cleveland Cavaliers.) Both of us take 600 mg to 1,000 mg a day of the DHA form. Need a reminder about why? There’s convincing evidence that DHA omega-3s are brilliant inflammation fighters, and that they specifically excel at keeping your heart, joints, vision, memory, skin and sex life healthy. What’s more important?
Omega-3s and prostate cancer: Is there a link?
So you can imagine our reactions when, not long ago, we woke up to blaring medical headlines linking DHA omega-3s to aggressive prostate cancer. What?
The story read something like this: A nationwide study has found that men with prostate cancer who have the highest levels of DHA omega-3s are 2.5 times more likely to have aggressive prostate cancer than men with the lowest DHA levels. And there was another total shocker: The study also found that men with the highest levels of trans-fats — yep, the scary stuff tied to inflammation and heart disease — had a 50 percent lower chance of having aggressive prostate cancer. Had the world turned upside down? Should men stop eating omega-3-rich salmon and trout and go back to trans fat-jammed doughnuts and fries?
After our households calmed down (Dr. Mike’s wife, Nancy, is also a doc, and Lisa Oz is intensely involved in mind-body health), we checked the original study. It was big (3,400 guys). Check. The work was done at a major cancer research center. Check. The results were published in a solid journal. Check. So what would explain such baffling results? Could there have been toxins in the fish oil capsules the men took to get their omega-3s? (FYI: We take algae-based omega-3 supplements, not fish oil capsules, to avoid mercury, PCBs and other toxins that fish can’t avoid.) Could it be coincidence that aggressive prostate cancer decreased in men who’d just spent two decades eating foods filled with risky trans fats? (The data was collected right before the world got wise to trans fats.)
After a serious talk, we reverted to two basics of Good Science:
1. This study is interesting, as well as surprising, and it raises new questions about diet, inflammation and disease. But it’s not “stop the presses!” research, although some reporters reacted that way. Our major concern is that, while it’s very good work, it’s an epidemiological study. And “epi” studies are population studies, which means they look for interesting links. They’re not cause-and-effect studies. This research found a link, not a cause, between omega-3s and aggressive prostate cancer. And it found a link, not a cause, between trans fats and decreased prostate cancer. A good epidemiology study says one thing (warning! hoary cliche coming up): More research is needed.
2. When a provocative new study is announced, we always wait for at least (underline that) three other studies to confirm it. In most cases (underline that, too), one study isn’t enough to change our behavior or our advice to you. The rare exception is a randomized controlled trial (the gold standard of research) that has an outrageously high probability of being right. Even then, you gotta be cautious. For example, the “this changes everything” study that showed taking vitamin E reduced heart disease had all this going for it … and still turned out to be wrong.
That’s why we wait for at least three more studies. Four is better.
One more thing: You’ve gotta weigh risks. To us, not taking omega-3s because they’ve been linked to aggressive prostate cancer — and by not taking them, upping your risk of heart disease, brain problems and vision loss — is like saving your pinky while cutting off both your essential opposing thumbs. OK, so that’s not a perfect analogy, but you get the point. It’s BS (Bad Science). Here’s why: The real-life effect of the omega-3 link in this study (if it turns out to be true) would increase deaths from aggressive prostate cancer by less than 0.5 percent. The increases in heart disease, vision damage and memory loss from not taking DHA omega-3s would be much, much bigger, maybe even 16 times greater.
So we’re continuing to take our daily algae-based DHA omega-3 supplements. We think you should, too. We’re continuing to avoid trans fats. We think you should, too. (Sorry about the fries and doughnuts, guys, but for every serving you have, put aside $20 for cardiac surgery.) And we’re continuing to watch the morning headlines, waiting for more data. We’ll keep you posted right here.
The YOU Docs, Mehmet Oz and Mike Roizen, are authors of “YOU: On a Diet.” Want more? See “The Dr. Oz Show” on TV. To submit questions, go to www.RealAge.com.