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Omega-3 Fatty Acid Supplementation and Atrial Fibrillation (AFib) Risk

September 27, 2021

Recent news reports indicate that omega-3 fatty acid intake may increase the risk of atrial fibrillation. Nina Radford (Director of Clinical Research at Cooper Clinic) explains the findings of recent medical studies and after that gives her opinion about how they will impact her recommendations to patients.

Q: What is atrial fibrillation?

A: Atrial fibrillation (AFib), the most common arrhythmia. It is diagnosed in clinical practice. According to the American Heart Association, at least 2.7 million Americans have AFib. The Centers for Disease Control and Prevention estimates that AFib affects 9% of people over 65.

AFib refers to an irregular heart rhythm. Furthermore, It occurs when the normal pacemaker function in the heart’s electric system is overwhelmed by random impulses from different locations within the upper chambers. AFib can be associated with rapid heart beat (>150 beats per minute) in some patients. However, other patients may not notice any changes due to certain medications or age-related changes that slow down impulses. Although, AFib risk may be temporary (paroxysmal), It could be persistent or permanent also.

AFib can be completely unsymptomatic for some patients. However, It may be detected by smart watches or may cause an error during home blood pressure monitoring. Besides, AFib can also cause symptoms such as palpitations, racing heartbeat, decreased exercise tolerance, or shortness of breath at rest.

Q: Is AFib dangerous?

A: The upper chambers of your heart can quiver with AFib and beat in a steady rhythm. However, stasis of Blood, which is associated with blood clot development, can occur in the nooks or crannies in your upper heart chambers (right & left atria). A blood clot consequently, may break loose in the left atrium, travel through the neck arteries and into the brain, leading to a stroke.

AFib thus increases the risk of stroke in older patients and those with preexisting cardiovascular risk factors like diabetes and hypertension. Strokes are above all more common in patients with cardiovascular conditions like heart disease or vascular disease. Males are most importantly at higher risk than females. In order to reduce stroke risk in high-risk patients, prescribing strong blood thinners could be a good choice.

Q: How should we treat AFib?

A: AFib treatment may include prescription blood thinners in high-risk patients, or for patients scheduled for cardioversion (a procedure that uses an electric charge to restore normal heart rhythm). Patients may be prescribed medications. These medications to restore or maintain normal heart rhythms. Meanwhile, some patients may need to undergo ablation, a more invasive procedure that permanently eliminates the electrical signals from the upper chambers of the heart that can cause AFib.

Q: Who is at risk for AFib?

A: As you age, your risk of developing AFib is higher. A number of clinical conditions can increase the risk of developing AFib. However, most of them can be avoided or treated.

  • High blood pressure
  • Obesity
  • Diabetes
  • Heart disease includes heart valve problems, previous heart attacks, heart failure, and chest pain caused by worsening coronary artery blockages.
  • Excessive alcohol consumption
  • Smoking
  • Physical inactivity
  • Obstructive sleep apnea
  • Hyperthyroidism
  • Acute severe systemic illness, such as pneumonia
  • Asthma and other chronic respiratory diseases like it are can be.

Middle-aged athletes are thus at higher AFib risks due to their involvement in endurance sports. Endurance sports is of high intensity for a long time.

Q: Is there a correlation between omega-3 supplementation and AFib risk?

Two recent clinical studies have shown a correlation. 4 gram of omega-3 EPA per day or placebo in the REDUCE-IT trial was given to around 8179 patients. They were high-risk patients with cardiovascular disease. The STRENGTH trial treated another high-risk group, 13,086 patients, with 4 grams of DHA and omega-3 EPA daily. This was in addition to the placebo. Both treatment groups experienced a significant increase in AFib risk after nearly five years. Moreover, the trials involved high-risk patients with atherosclerotic heart disease, type 1 or 2 diabetes, and those on statin therapy with elevated triglycerides. Other risk factors include family history, high C-reactive proteins, impaired kidney function, or coronary artery calcium levels above 300.

Cooper Complete Advanced Omega-3 has 1.4g (1,400mg) of EPA/DHA per two soft gel daily doses. It is important to remember that seven Advanced Omega-3 Softgels are equal to the amount of Omega-3 Supplementation used in these trials.

Q: What does the research from the VITAL Rhythm Study show?

A: The VITAL Rhythm Study (also known as VITamin D/OmegA-3 TriaL) examined 25,871 people to determine if 50 mcg (2,000 IU), or 1 gram of Omega-3, or both, reduced stroke, cancer, and heart disease risk. To determine if AFib was developing, the investigators also analyzed data from the trial. The participants were healthy. They never had any diagnosis with any type of cancer or cardiovascular disease who were in this trial. This is contrary to previous studies. Researchers did not find an increase in AFib and omega-3 risk in the group that received 1 gram each of DHA and EPA daily.

Dr Radford shares 5 key points about the VITAL Study Omega-3 and the prevention of cardiovascular disease.

Below is a summary table of data from four trials involving AFib. These trials do not had AFib development as primary outcome. However, It has an adverse effect according to the report.

Q: How do the results of these studies change how you treat your patients?

A: Consuming 4g per day of omega-3 fatty acid supplement. AFib is certainly associated with a higher risk in this case. I advise that high-risk patients consume less.

What could be less? One small study, OMEMI, involved older Norwegians who had suffered a heart attack in the past. They were given 1.8 grams of omega-3 fatty acid daily or a placebo. The trial did not show an increase in AFib risk. This clinical trial did not show an increase in AFib risk. I recommend that patients at higher risk consume 2 grams of omega-3 daily to prevent atrial fibrillation. Some of these patients may need to take higher dosages of omega-3 supplements in order to treat other conditions such as high blood triglycerides. Sometimes, we need to evaluate the risks and benefits of each treatment individually.

Q: Should high-risk patients also limit the omega-3 intake in their diet?

A: These studies do not address the association between dietary intakes of omega-3 and the risk of developing AFib. Because most people don’t consume enough omega-3, I don’t recommend that patients reduce their intake. I would still recommend that patients include these omega-3 fatty acid-rich foods in their diets. Primary results from the VITAL Study (also used in the VITAL Rhythm Study previously mentioned) demonstrated the value of omega-3 fatty acid from dietary sources. To reduce cardiovascular risk, it was therefore, not beneficial to add 1 gram omega-3 per day to participants who ate more than two servings of fish per semaine. Moreover, Participants who did not consume more than one serving of fish per week saw a 20% reduction in their chance of suffering a heart attack, stroke, or death due to cardiovascular disease if they added 1 gram of omega-3 daily.

Above all, your health care provider is the best person to understand your health. This includes your medical history, risk factors, current medication, and supplement use. Hence, talk to your doctor about the best supplements for you, including omega-3.

Nina B. Radford MD, Cooper Clinic Cardiologist, and Director of Clinical Research, provides information about Omega-3 and AFib risk.


Bhatt DL, Steg PG, Miller M, et al.; REDUCE-IT Investigators. Cardiovascular risk reduction with icosapent ethyl for hypertriglyceridemia. N Engl J Med. 2019;380(1):11-22. doi:10.1056/NEJMoa1812792

Kalstad AA, Myhre PL, Laake K, et al; OMEMI Investigators. A controlled, randomised trial investigating the effects of n- fatty acids supplementation on elderly patients following myocardial injury. Circulation. 2021;143(6):528-539. doi:10.1161/CIRCULATIONAHA.120.052209

Nicholls SJ, Lincoff AM, Garcia M, et al. The STRENGTH clinical trial randomized to high-dose omega-3 oils vs. corn oil in adverse cardiovascular events in patients with high cardiovascular risk. JAMA. 2020;324(22):2268-2280. doi:10.1001/jama.2020.22258

Albert CM, Cook NR, Pester J, et al. A randomized clinical trial evaluating the effects of vitamin D and marine omega-3 fatty acids on incident atrial fibrillation. JAMA. Published March 16, 2021. doi:10.1001/jama.2021.1489