The advisory, published on Monday, looked at the evidence backing omega-3 supplementation in the prevention of already-diagnosed cardiovascular disease. The authors looked at the accumulated evidence from randomized, controlled trials (RCTs) to assess the efficacy of omega-3 supplementation in helping patients suffering from cardiovascular disease to avoid recurring episodes or symptoms.
“Although recent RCT evidence has raised questions about the benefits of omega-3 supplementation to prevent clinical CVD [cardiovascular disease] events, the recommendation for patients with prevalent CHD [coronary heart disease] such as a recent MI [myocardial infarction] remains essentially unchanged: Treatment with omega-3 PUFA supplements is reasonable for these patients. Even a potential modest reduction in CHD mortality (10%) in this clinical population would justify treatment with a relatively safe therapy,” the authors concluded.
“In general I think the communication is positive,” said Adam Ismail, executive director of the Global Organization of EPA and DHA Omega-3s (GOED). “They are basically validating the supposition that EPA and DHA can have a positive effect on heart health, especially for this specific population.”
“Science demonstrating the benefit and safety of omega-3 fatty acids for heart health is well-established and this science advisory from the American Heart Association reaffirms this fact. CHD is a serious condition, and we support the AHA’s recommendation that people with CHD use omega-3 fatty acids in consultation with a doctor,” said Andrea Wong PhD, vice president of scientific and regulatory affairs for the Council for Responsible Nutrition.
Good for some things, not for others
The advisory broke the effect of omega-3 supplementation down into a number of subsets of heart disease. The authors concluded there was good evidence for a positive effect for some of these indications, such as patients with a recent myocardial infarction and/or prevalent coronary heart disease. But they said there was not enough supporting evidence from RCTs to recommend supplementation in other cases, such as for preventing strokes or in cases of patients suffering from prevalent atrial fibrillation.
What the report did not do was recommend the use of EPA and DHA to prevent the development of cardiovascular disease in the first place. Ismail said this point has been misconstrued a bit and has been taken to mean that the authors didn’t think omega-3s could have this prophylactic benefit. Rather, he said, it’s a case that there were no RCTs that met the authors’ criteria that looked at this end point.
“This advisory is very specific for cardiovascular disease and related outcomes. They didn’t say there was no benefit for prevention in the general population. They just said that there was not enough evidence in the form of large-enough RCTs,” he said. GOED did note that a large-scale trial looking at these end points is underway.
Evidence for prevention
Both Ismail and Wong said that in the meantime there is a significant amount of evidence from smaller scale trials and in the form of meta-analyses (which were considered by the AHA authors but given a lower rank than RCTs in terms of evidence) to support the use of omega-3s both for CHD prevention and for the support of general health.
“Even though this advisory focused on major disease endpoints, we should not discount the significant amount of research that supports the role of omega-3s on other relevant endpoints, such as reducing triglycerides and blood pressure, which potentially help healthy adults prevent cardiovascular disease,” Wong said.
“This advisory doesn’t mean that there isn’t ample evidence for all of these endpoints,” Ismail said. “In the AHA’s previous guidance they have talked about eating enough fatty fish. If you are not doing that, we would say that supplementation is called for to get enough omega-3s to support general health.”
“Omega-3 fatty acids are important for overall health and the benefits of this nutrient from food and dietary supplements go beyond cardiovascular health, providing support for perinatal health, inflammation, and cognitive function. Ideally people should strive to eat a diet high in fatty fish, such as salmon and sardines, in order to obtain omega-3 fatty acids, but realistically, as data show, most people are not doing this,” Wong said.