Are omega-3 fatty acid supplements part of your daily routine? Recommendations of intake vary worldwide but typically include oily fish intake or supplementation to reduce the risk of heart disease, stroke, and death. The Cochrane Library recently published an extensive systematic assessment of the effects of omega-3 fatty acids on cardiovascular health.
According to the review, three main types of omega-3 fats are eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and alpha-linolenic acid (ALA). EPA and DHA are found in fish, and ALA is found in plant foods.
According to an interview with Dr. Lee Hooper, who worked on the study, the team assessed the effectiveness of long-chain omega-3 fats as oily fish or supplements and alpha-linolenic acid (ALA) as foods or supplements. To conduct this assessment, the team reviewed randomized trials (dated up to February of 2019) examining the effects of increasing fish and plant-based omega-3s on heart and circulatory diseases, fatness and blood fats, and cholesterol.
The review found little or no effect of increasing long-chain omega-3 on all-cause mortality, cardiovascular mortality, cardiovascular events, stroke, or arrhythmia. However, increasing these omegas may slightly reduce the risk of coronary death or coronary events, but the effects are minimal. The review also found no effect on fatness, lipids, or blood pressure. Increasing omega-3s may reduce triglycerides by 15%, but results are dose-dependent.
Increasing ALA is considered the vegetarian or vegan way to increase omega-3 fatty acids. The study reports that increased ALA may slightly reduce the risk of cardiovascular disease events and arrhythmia, but the effects are small. Increased ALA intake probably makes little or no difference to “all-cause mortality, cardiovascular mortality, coronary disease mortality, and coronary heart disease events.”
They did not find additional trials to review that included increased oily fish intake, and cannot fully understand the effects of oily fish intake on cardiovascular health. However, Dr. Hooper says that even without the cardiovascular benefits, fish and seafood are nutritious and useful to diets.
So, why are leading medical institutions still recommending omega-3s to reduce the risk of heart disease and cancer? Dr. Hooper told the New York Times the evidence does not support the recommendations. She stated, “We’ve tried to get it right, we’ve tried to make sure all the details are there. We’ve tried to check every way to make sure we’re not missing something. And all we see is these tiny harms and benefits that appear to balance each other out.”
Sources: New York Times, Cochrane Library, Cochrane
