There are some mixed views on whether fish oil can cause abnormal heart rhythms or not. Generally speaking, most healthy people don’t need to worry: A meta-analysis of 30 randomized studies and 77,990 patients shows that taking fish oil does not affect the risk of atrial fibrillation.[1] However, in people who have (or are at risk for) heart disease, there’s a possibility that fish oil can increase the risk of new-onset atrial fibrillation. Several meta-analyses of randomized studies at least one year long in people with or at risk for cardiovascular disease show that fish oil can increase the risk of new-onset atrial fibrillation compared to control.[2][3][4] It’s important to note that, while this increase in risk is statistically significant, it’s still small in absolute terms and there is no known mechanism to explain this risk.
References
- ^Asmaa S Abdelhamid, Tracey J Brown, Julii S Brainard, Priti Biswas, Gabrielle C Thorpe, Helen J Moore, Katherine Ho Deane, Carolyn D Summerbell, Helen V Worthington, Fujian Song, Lee HooperOmega-3 fatty acids for the primary and secondary prevention of cardiovascular diseaseCochrane Database Syst Rev.(2020 Feb 29)
- ^Baris Gencer, Luc Djousse, Omar T Al-Ramady, Nancy R Cook, JoAnn E Manson, Christine M AlbertEffect of Long-Term Marine Omega-3 Fatty Acids Supplementation on the Risk of Atrial Fibrillation in Randomized Controlled Trials of Cardiovascular Outcomes: A Systematic Review and Meta-AnalysisCirculation.(2021 Oct 6)
- ^Bae JH, Lim H, Lim SThe Potential Cardiometabolic Effects of Long-Chain ω-3 Polyunsaturated Fatty Acids: Recent Updates and Controversies.Adv Nutr.(2023-Jul)
- ^Marco Lombardi, Salvatore Carbone, Marco Giuseppe Del Buono, Juan Guido Chiabrando, Giovanni Maria Vescovo, Massimiliano Camilli, Rocco Antonio Montone, Rocco Vergallo, Antonio Abbate, Giuseppe Biondi-Zoccai, Dave L Dixon, Filippo CreaOmega-3 fatty acids supplementation and risk of atrial fibrillation: an updated meta-analysis of randomized controlled trialsEur Heart J Cardiovasc Pharmacother.(2021 Jul 23)