Can Fish Oil Actually Worsen Heart Health?

Researches have been hard at work following up some earlier studies which suggested that fish oils, specifically the omega-3 fatty acids EPA and DHA improved heart health by lowering the risk for heart attack and related health issues. What they found, however, were hints that fish oil could actually worsen heart health.

The STRENGTH trial, completed in 2020, looked at whether a high dose (4 g/day) of a prescription combination EPA/DHA omega-3 fatty acid (fish oil) would improve heart health in an at-risk population compared to corn oil. Following the successful REDUCE-IT trial, done 2 years earlier which looked at a unique formulation of EPA omega-3 fatty acid, most experts anticipated that a combination of EPA/DHA would be similarly effective. Unfortunately, the study was ended early because there was no sign of benefit to the study subjects when compared to the corn oil placebo. In fact, there was a 67% increase in atrial fibrillation, a serious heart arrhythmia which can cause a stroke if not treated. This has brought up many questions regarding omega-3 fatty acids and their role in cardiovascular disease prevention.

The details of the study, however, may provide some clues as to the lack of benefit to patients enrolled in the STRENGTH trial. Of note, the EPA blood levels reached in the STRENGTH patients were less than half of those who were involved in the REDUCE-IT trial. This relatively low level of EPA may suggest that there exists a minimum daily dose in order to provide cardiovascular benefit. 

The following video created by the Cleveland Clinic does a great job of summarizing the study. 

If you would like to discuss if omega-3 fatty acids are right for you, don’t hesitate to contact us.