The debate on fish oil supplements rages on.

A new study by Dutch scientists found that low doses of omega-3 fatty acids provided little to no help preventing future heart attacks in patients with a history of heart disease. As published in the New England Journal of Medicine, researchers followed 4837 patients for 40 months and gave each supplements containing docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), as found in fish oil, and/or alpha-linolenic acid (ALA), as found in certain nuts and vegetables. All patients had previously had a myocardial infarction (heart attack). By examining which patients had (another) MI during the 40 months of observation, the researchers determined that these fatty acids weren’t helping. Does this spell the end for fish oil supplements? Hardly. The Dutch work is important, but still leaves many questions unanswered.

This research comes in contrast with previous experiments which showed that fatty acids could significantly reduce the risks of heart attacks when taken regularly as a supplement. The nearly 5000 patients in the Dutch study received the Omega-3s in amounts comparable to previous tests (400mg for DHA/EHA or 2g for ALA per day – disguised in identical tasting sticks of margarine). But when comparing the recipients of supplements to those of placebo, the fatty acids didn’t seem to provide protection against MI. Of the 4800+ patients, 671 had a heart attack during the trial. The Dutch scientists, led by Daan Kromhout of Wageningen University, gave several reasons in their paper for why the discrepancy may have arisen.

The first idea is that the Dutch patients were mostly old men. Average age was 69 (range of 60 to 80) and 78% were male. Other tests for fatty acid supplements covered different ranges of age, and many focused on women. In fact, the Dutch researchers did find some indication that the women in the study benefited slightly from receiving ALA.

Another possible culprit (perhaps the most likely) is that all patients were receiving top of the line medical care. As all previously had experienced MI, they were being dosed with start of the art medications to prevent further heart attacks. 85% of the patients were taking statins. Kromhout and his colleagues suggest that this medical care may have had a profound enough life-saving effect that the bonuses from fatty acid supplements were negligible. If so, the experiment would not have been particularly insightful into the effects of omega-3s, but it would be a good sign that modern medicine really helps with MI.

The final major possibility is that the Dutch patients were outside the time in which fatty acids may have helped with heart disease. Patients had experienced their heart attacks an average of 4 years before the study began. Other trials for fatty acids had begun treating patients with supplements much closer to the original MI. There may be some optimal time after (or before) MI for taking fatty acids as a supplement.

I encourage you to read the NEJM article on this study – as far as medical publications go it’s pretty accessible. But I don’t think we can draw any definitive conclusions from this work. Yes, 4837 patients over 40 months is a good data set, but the study had its limitations as the authors discussed. As we mentioned earlier, a much larger study (20,000 patients) is forthcoming from the US National Institute of Health which should shed much needed light on the effects of fish oil and vitamin D. That study, however, will have its own limitations in terms of patient selection, just like the Dutch research. The truth is that while each study provides new data, we’re likely to need years of more trials before we can write the definitive word on fish oil. Hopefully, however, we’ll eventually collect enough information that we can reasonably understand if and when fatty acids will help protect your heart. When that happens we’ll have another tool in our kit for keeping us healthier and happier longer.

[image via thinkorthwim.com]
[source: Kromhout et al, NEJM 2010]

Do I need to catch more sun and vitamin D?

The western world faces three very notorious killers: heart disease, cancer, and stroke. Just this week Michael Jackson (heart attack??) and Farah Fawcett (cancer) were struck down, and the media is waiting on baited breath for another celebrity to die and fulfill the “rule of threes.” Stroke, we’re looking at you. But what if it didn’t have to be this way? What if there were just a few simple things you could eat or take that would protect you from all three killers?

That’s what the U.S. government is going to find out. The National Institute for Health (NIH) is funding a $20 million dollar study with 20,000 test subjects to explore how vitamin D and fish oil affect health. The Vitamin D and Omega-3 Trial (or VITAL) will be a five year study and will be one of the first to specifically target African Americans as test subjects. With darker skin producing less vitamin D in the body from sun exposure, scientists theorize there may be a link between a vitamin D deficiency and higher rates of stroke, heart disease, and cancer in the Af.Am. community.

Vitamin D and Fish Oil. Not quite the names for a buddy cop movie, but for the last decade, they’ve each been toted as the way to combat the killer diseases of our time. Vitamin D has been inconclusively linked to heart health and cancer prevention, not to mention bone strength. Fish Oil, with high levels of vitamin D and omega-3 fatty acids is supposed to good for everything from good skin to memory loss. When it comes to preventing stroke, heart attack, or cancer, these two guys seem like the ideal dietary supplements to take.

And in five years, we’ll hopefully know for certain. In the meantime, Dr. JoAnn Manson and Dr. Julie Buring, the heads of VITAL are gearing up for the trials. Starting in January of next year, they will recruit men over the age of 65 and women over 60 to take daily supplements and report on their health. These supplements will be either placebos, vitamin D, or fish oil. While the studies will be centered at Harvard Medical School and the Brigham and Women’s Hospital in Boston, the subjects will cover the entire U.S. With a relatively huge sampling (20,000 subjects) and double blind methodology, VITAL hopes to once and for all settle the long term benefits, or risks, of vitamin D and omega-3 fatty acids.

If the tests can conclusively prove the health benefits for these supplements they’ll be a fixture in the diets of all those seeking longevity or immortality, such as Singularity Hub regular Ray Kurzweil. Even if vitamin D and fish-oil aren’t shown to be miracle drugs the VITAL study could still reveal important facts about our health. Terrifying or wonderful surprises come standard with studies this large. For instance, who could have predicted that chemotherapy would help with wrinkles? In five years, we may all be rushing outside to soak up more sun or eating more sushi to prevent cancer. Personally, I’ll be waiting for the day you can get vitamin D from the glow of your computer screen.