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Sea Change for Marine Omega-3s

Randomized Trials Show Fish Oil Reduces Cardiovascular Events
Published:October 15, 2019DOI:


      Recently, 3 large randomized controlled trials (RCTs) have assessed the effects of supplementation with marine omega-3 fatty acids on the occurrence of cardiovascular disease (CVD) events. We reviewed this evidence and considered it in the context of the large and growing body of data on the CV health effects of marine omega-3s. One RCT examining 8179 patients, most with coronary heart disease (CHD), reported that 4 grams/day of a highly purified omega-3 product containing eicosapentaenoic acid (EPA) reduced the risk for major adverse CV events by 25% ( P<.001). Two other recent RCTs in primary prevention populations showed that approximately 1 gram/day of purified fish oil containing 840 mg/day of EPA and docosahexaenoic acid (DHA) significantly reduced risks of CHD and CV death, especially in individuals who did not consume fish and seafood frequently. The American Heart Association (AHA) continues to emphasize the importance of marine omega-3s as a nutrient for potentially reducing risks of congestive heart failure, CHD, ischemic stroke, and sudden cardiac death. Marine omega-3s should be used in high doses for patients with CHD on statins who have elevated triglycerides and at about 1 gram/day for primary prevention for individuals who do not consume at least 1.5 fish or seafood meals per week.

      Abbreviations and Acronyms:

      AFIB ( atrial fibrillation), AHA ( American Heart Association), ALA ( α-linolenic acid), CHD ( coronary heart disease), CV ( cardiovascular), CVD ( cardiovascular disease), DHA ( docosahexaenoic acid), DPA ( docosapentaenoic acid), EPA ( eicosapentaenoic acid), hsCRP ( high-sensitivity C-reactive protein), HR ( hazard ratio), IPE ( icosapent ethyl), LDL-C ( low-density lipoprotein cholesterol), LV ( left ventricle), LVESVI ( left ventricular end-systolic volume index), LVEF ( ventricular eject faction), MRI ( magnetic resonance imaging), MACE ( major adverse CV events), MI ( myocardial infarction), O-3FA ( omega-3 fatty acids), PUFA ( polyunsaturated fatty acid), RBC ( red blood cell), RCT ( randomized controlled trial), TG ( triglyceride)
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