About a week ago, a meta-analysis was released on “Associations of Omega-3 Fatty Acid Supplement Use With Cardiovascular Disease Risks”. The study found that Omega-3 Fatty Acid (O3FA) supplementation DID NOT reduce the risk of heart diseases and stroke.
Omega 3 Fatty Acids and heart diseases
O3FA has long been studied and marketed as a supplement that reduces triglycerides which in terms lowering the risk of heart disease as well as stroke. High triglycerides and also inflammation are associated with heart diseases and stroke. O3FA was shown by previous studies that it not only reduces triglycerides level, but also reduces inflammation. Hence it is postulated that through these two mechanisms, it will reduce risks for heart disease and stroke.
It is noted in observational studies that regular consumption of fish once to twice weekly is associated with reduced risk of death from heart disease. It was these studies along with lower rates of heart disease in populations that consumed large amount of foods rich in OF3A that prompted the idea that consumption of O3FA may confer a heart-protective effect.
A study called Diet and Reinfarction Trial-1 found that men who had a heart attack and consumed oily fish twice or more per week had significantly reduced risk of dying from heart attacks, but a repeated study called Diet and Reinfarction Trial-2 showed that men who had heart blockage had increased risk of dying from heart disease if they consumed fish or fish oil supplements. Further studies involving large sample sizes also yielded conflicting results.
The results of “Associations of Omega-3 Fatty Acid Supplement Use With Cardiovascular Disease Risks”
The “Associations of Omega-3 Fatty Acid Supplement Use With Cardiovascular Disease Risks” study is a meta-analysis where the results of many trials (10 trials to be exact with a total sample size of 77,917 high-risk individuals) are pooled together to provide more reliable statistical data in order to prove or disprove the use of O3FA in reducing risk of heart disease.
The results from this study showed that O3FA supplementation DID NOT reduce the risk of heart diseases and stroke. This observation is consistent through all subjects with or without existing heart disease or stroke. Both healthy and unhealthy people did not receive any protective effects against heart disease or stroke according to the results.
What it also showed was that consuming O3FA also do not increase the risk of heart disease or stroke as suggested in the Diet and Reinfarction Trial-2.
Due to the large population size and the well-designed study methodology, the results are highly reliable with very low risk for errors.
This study is not without limitations. Of the 10 trials included, one of the trial (JELIS) involving 18,645 participants did not provide raw data for the investigators in this trial to analyse.
This study looked at O3FA supplementation of eicosapentaenoic acid with a dose range of 226-1800mg daily. There are ongoing trials with higher doses of O3FA supplementation being studied and their results may prove otherwise.
Should I take O3FA then?
If you are already taking or considering taking O3FA at doses of approximately 1 gram daily, there is no incentive to continue or start, according to this study. At this point, there is no benefit nor harm, hence it is completely up to the individual whether he/she wants to take the supplement.
From a practitioner’s point of view, there is absolutely NO reason to spend money on medications or supplements that have been shown to NOT provide any benefit even though it is harmless.
Higher doses of O3FA (much more than 1g daily) may still potentially provide benefits, but until the results of studies on high doses are released, it is also NOT recommended.
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