Just to prove once again that nutrition is not a black-and-white subject, two studies just released found that the omega-3s do not help reduce heart disease risk. One study from the University of Cambridge found that people who take fish oil did not show any lower risk for coronary events. A second study reviewing the use of omega-3s for eye health, also looked at whether or not supplements would help prevent heart attack, stroke, or heart failure. That study also found no effect. Does this mean we should stop eating salmon or taking our fish oil capsules? Probably not.
The results of these two studies contradict a wealth of previous research showing the omega-3s in fatty fish are helpful in lowering cardiovascular disease, evidence so strong that recommendations to increase these fats come from reputable groups, including numerous government, academic, nutritional, and medical organizations and experts. The first study was conducted on people with existing cardiovascular disease and elevated risk factors at baseline. It also pooled data from studies using anywhere from 0.3 to 6.0 grams of omega-3s/day, which easily could have diluted the effects and potentially contributed to the lack of statistical significance. The second study began supplementation later in life to people who very well could have had existing risk factors for heart disease. It also required drug-like criteria to reach statistical significance. In other words, the researchers acknowledged that given the sample size they started with, they would have had to see a 25% risk reduction to find significance. This is realistic for testing medications, but not for testing nutritional supplements. Once again, these studies are a reminder to look at the tapestry of studies on any one nutritional topic, and to never take action based on one, or even a handful, of studies.
Bonds et al: Effect of long-chain omega-3 fatty acids and lutein + zeaxanthin supplements on cardiovascular outcomes. JAMA Internal Medicine 2014;March 17th.
Chowdhury R, et al: Association of dietary, circulating, and supplement fatty acids with coronary risk. Annals of Internal Medicine 2014; March 17th.