A new meta-analysis led by researchers from the Fatty Acid Research Institute (FARI) provides the clearest picture to date of the relationship between omega-3 fatty acid supplementation and atrial fibrillation (AF), helping resolve years of confusion generated by earlier reports.
Published in Circulation: Arrhythmia and Electrophysiology , the study, led by Dr. Nada Abuknesha, PhD, an Associate Scientist at FARI, analyzed data from 35 randomized controlled trials involving 114,592 participants—more than four times the number of studies included in previous meta-analyses. Researchers also incorporated unpublished trial data and previously unavailable safety information to provide the most comprehensive assessment of AF risk to date.
The Key Finding
The analysis found that low-dose omega-3 supplementation (less than 1,500 mg/day EPA+DHA) was not associated with an increased risk of AF, even among individuals at elevated cardiovascular risk.
In contrast, only in the setting of high-dose omega-3 therapy (>1,500 mg/day, typically prescription-strength formulations) used in patients with established cardiovascular disease was AF risk modestly increased (i.e., the absolute risk increase was 0.8%).
"Our findings show that the relationship between omega-3s and atrial fibrillation is much more nuanced than previous headlines suggested," said William S. Harris, PhD, President of the Fatty Acid Research Institute (FARI) and senior author on the study. "For the vast majority of people taking nutritional doses of omega-3s, these data should provide reassurance that there is no meaningful increase in atrial fibrillation risk."
Addressing a Long-Standing Controversy
In recent years, several meta-analyses suggested that omega-3 supplements may increase the risk of AF. However, those reports included no more than eight randomized trials, focused primarily on cardiovascular outcome studies, and did not account for many eligible trials where AF data were available but unpublished.
The new FARI-led analysis expanded the evidence base substantially by:
Including 35 randomized controlled trials involving 114,592 participants
Incorporating 15 trials containing previously unpublished AF data
Including studies reporting zero AF events, reducing publication bias
Evaluating risk according to both omega-3 dose and underlying cardiovascular risk, providing a more clinically meaningful interpretation of the evidence.
Putting the Findings Into Clinical Context
Researchers emphasize that even among high-risk cardiovascular patients receiving prescription-level omega-3 doses, the observed increase in AF should be weighed against the well-established cardiovascular benefits demonstrated in major clinical trials.
For example, previous studies of high-dose EPA have shown reductions in heart attacks, stroke, and other major cardiovascular events that substantially outweigh the small increase in atrial fibrillation risk.
"The decision to take or discontinue omega-3 supplements should be a discussion between a patient and his/her healthcare provider," said Harris. "What this study does is provide clinicians with better guidance on which patients may benefit from closer monitoring when using high-dose omega-3 therapies while reassuring consumers that it is safe to consume omega-3 fatty acids from foods and dietary supplements."
Implications for Consumers and Clinicians
The findings reinforce an important distinction between:
Nutritional omega-3 supplementation (typically 500-1,500 mg/day), commonly used to support general health and cardiovascular wellness.
Pharmacological omega-3 therapy (typically 2-4 grams/day), prescribed for individuals with elevated triglycerides or established cardiovascular disease.
The authors emphasize that AF risk profiles should be evaluated separately for each category, as nutritional doses do not carry the same clinical implications as higher pharmacological doses.
About the Study
The study, Effects of Omega-3 Fatty Acid Treatment on Risk for Atrial Fibrillation: An Updated Meta-Analysis of 35 Trials Including 114,592 Individuals, was led by researchers from the Fatty Acid Research Institute in collaboration with investigators from institutions worldwide. The systematic review included published and unpublished randomized clinical trial data and represents the largest analysis to date examining omega-3 supplementation and incident AF.
Disclaimer: This publication from FARI was commissioned by the Global Organization for EPA and DHA Omega-3s (GOED). GOED did not have any input into the study design, data analysis or interpretation.
Circulation Arrhythmia and Electrophysiology
Meta-analysis
People
Effects of Omega-3 Fatty Acid Treatment on Risk for Atrial Fibrillation: An Updated Meta-Analysis of 35 Trials including 114 592 Individuals
28-Jul-2026