Don’t rely on fatty acid supplements for protection against heart disease

The Bottom Line

  • Fatty acids such as omega-3 and omega-6 provide important health benefits, including helping to reduce the risk of heart disease.

  • Omega-3 fatty acids are found in certain fish as well as in some types of nuts and seeds.

  • Research involving fatty acid supplements and heart disease has resulted in mixed findings; supplements may help lower blood pressure, but they don’t prevent heart attacks in people already diagnosed with heart issues.

If you visit any pharmacy these days you’re sure to be amazed by the dizzying array of vitamins and supplements available for purchase – literally everything from (vitamin) A to Z(inc) in various forms, sizes and strengths. People take them to make up for deficiencies in their diets, boost their immune systems, fight disease and promote overall good health.

Fatty acid supplements have been of particular interest as more information comes to light about the important role fatty acids play in maintaining optimal health, including reducing the risk of heart disease. They include omega-3, which you get from eating certain kinds of “fatty” fish (e.g. salmon, tuna, mackerel) and from plant sources such as nuts and seeds. Nutritional guidelines suggest at least two servings of fatty fish a week (1). Omega-6, another fatty acid, is also found in nuts and seeds, as well as vegetable oils (2).

As many people can’t – or don’t want to – get their omega-3 and omega-6 fatty acids from food, supplements would appear to be an effective alternative (3) and several research studies have attempted to determine whether, in fact, they are. A recent systematic review focused specifically on people who already had heart issues (such as coronary artery disease, angina, irregular heartbeat) and tried to find out if taking fatty acid supplements would help prevent heart attacks (4). The review included 27 randomized controlled trials and involved more than 105,000 people. Some study participants (intervention group) were given either plant or fish-based omega-3 or omega-6 fatty acid supplements and others were not (control group).

What the research tells us

There was virtually no difference in the number of heart attacks suffered by people taking the supplements compared to the control group. Fish-based omega-3 supplements appeared to have a slight beneficial effect on heart health but the evidence was not conclusive.

The authors of the review acknowledge limitations with some of the included studies and urge further research, especially as there have been more encouraging results from related studies. For example, another recent systematic review found that fish oil supplements may help lower blood pressure.

That could potentially prevent future problems for many. But people coping with pre-existing heart conditions may want to pass on the fatty acid supplements in favour of more proven treatments.

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Author Details


  1. Mozaffarian D, Wu JH. Omega-3 fatty acids and cardiovascular disease: effects on risk factors, molecular pathways, and clinical events. JACC. 2011; 58(20): 2047-2067. 
  2. Simopoulos AP. The importance of the omega-6/omega-3 fatty acid ratio in cardiovascular disease and other chronic diseases. Exp Biol Med. 2008; 233(6): 674-688. 
  3. Mozaffarian, op. cit. 
  4. Chowdhury R, Warnakula S, Kunutsor S et al. Association of dietary, circulating, and supplement fatty acids with coronary risk: a systematic review and meta-analysis. Ann Intern Med. 2014; 160:398-406

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