Atrial Fibrillation
Supplements studied for atrial fibrillation.
Overview
Six supplements are indexed for atrial fibrillation across 32 studies.
Vitamin C (WA 68; medium effect size, high evidence, high trust) may lower post–heart surgery atrial fibrillation risk by roughly 27–53% when taken orally at 1–2 grams daily around the procedure, though U.S. trials have been null. Fish Oil (WA 44; very low effect size, very high evidence, medium trust) does not prevent atrial fibrillation in most research and higher doses may increase risk.
Vitamin D (WA 36; very low effect size, medium evidence, medium trust) showed no benefit in a large healthy-adult trial but possible benefit in some older or deficient subgroups. Early berberine data (WA 44) and caffeine (WA 32; very low effect size, low evidence, medium trust) add limited signals. See the heatmap and evidence reviews below.
Effect graph
Relevant supplements
Relevant supplements sorted by DEX Score.
Studies
Find individual evidence reviews for supplements sorted by DEX Score.
6 supplements for , and rated at least stars. All purchase bands. No minimum star filter.
Vitamin CView supplement →
Consider purchase·★★★★★
How we scored this▸
- Taking vitamin C before and after heart surgery can lower the chance of irregular heartbeat (atrial fibrillation) afterward by about 27% to 53%.
- Most studies used 1–2 grams daily a few days before and after surgery.
- Vitamin C taken by mouth may work better than through a vein.
- Some studies in the U.S. didn’t find a benefit, possibly due to differences in diet or hospital care.
- Taking vitamin C with fish oils (EPA and DHA) might also help prevent atrial fibrillation.
Browse 4 studies·3 meta-analyses
MetaEfficacy and safety of vitamin C for atrial fibrillation after cardiac surgery: A meta-analysis with trial sequential analysis of randomized controlled trials2017n=1,060
A meta-analysis of 8 RCTs (1,060 cardiac surgery patients) found vitamin C reduced post-operative atrial fibrillation (OR 0.47) with moderate-quality evidence.
- Effect
- Benefit
- Population
- Adults
- Participants
- 1,060
MetaVitamin C for preventing atrial fibrillation in high risk patients: a systematic review and meta-analysis2017n=2,050
A meta-analysis of 15 cardiac surgery trials (2,050 patients) found vitamin C prevented post-operative AF outside the US (RR 0.56) but not in US trials.
- Effect
- Benefit
- Population
- High-risk patients
- Participants
- 2,050
- Avg age
- ~63.4
MetaAntioxidant supplementations for prevention of atrial fibrillation after cardiac surgery: an updated comprehensive systematic review and meta-analysis of 23 randomized controlled trials2014n=4,278
A meta-analysis of 23 cardiac surgery trials (4,278 patients) found vitamin C (OR 0.50), NAC, and PUFA each reduced post-operative atrial fibrillation.
- Effect
- Benefit
- Population
- Cardiac surgery patients
- Participants
- 4,278
RCTA randomized controlled trial to prevent post-operative atrial fibrillation by antioxidant reinforcement2013n=203
In 203 on-pump cardiac surgery patients, combined n-3 fatty acids 2 g/day plus vitamins C and E reduced postoperative atrial fibrillation to 9.7% versus 32% with placebo (p<0.001).
- Effect
- Benefit
- Dose
- 2 g/day
- Population
- Adults
- Participants
- 203
BerberineView supplement →
Reconsider purchase·★★★★★
How we scored this▸
- Early research suggests that berberine may help prevent irregular heartbeats after heart bypass surgery.
- One small study found that taking berberine three times a day for a week lowered the chance of developing atrial fibrillation by half compared to placebo.
Browse 1 study
RCTPreventive Effect of Berberine on Postoperative Atrial Fibrillation2022n=100
An RCT of 200 coronary bypass patients found oral berberine reduced postoperative atrial fibrillation incidence from 35% to 20% and lowered CRP and IL-6.
- Effect
- Benefit
- Population
- CABG patients
- Participants
- 100
Fish OilView supplement →
Reconsider purchase·★★★★★
How we scored this▸
- Taking fish oil supplements by mouth does not lower the risk of getting atrial fibrillation (an irregular heart rhythm), and higher doses may actually raise the risk.
- Most research shows that fish oil or eating fatty fish does not prevent new or returning cases of atrial fibrillation.
- Some studies found that taking high-dose fish oil increases the chance of developing this heart rhythm problem, especially at doses above 1 to 4 grams daily.
- In some people, a higher fish oil dose or certain types of fish oil may increase risk even more, especially in those with heart disease or risk factors.
- Fish oil does not appear to help people avoid atrial fibrillation after heart surgery, and the American Heart Association does not recommend it to prevent this condition in people who have already had it.
Browse 22 studies·10 meta-analyses
MetaMeeting highlights from the Pharmacovigilance Risk Assessment Committee (PRAC) 25-28 September 20232023
A periodic review of systematic reviews and meta-analyses of RCTs conducted by the Pharmacovigilance Risk Assessment Committee of the European Medicines Agency has found a dose-dependent increased risk of atrial fibrillation from omega-3-acid ethyl ester supplementation in individuals with established cardiovascular diseases or cardiovascular risk factors compared to placebo. The observed risk was greatest with a dose of 4 g/day. In cases of new-onset atrial fibrillation, treatment should be permanently discontinued. [10593] [View External Resource]
- Effect
- No Benefit
- Dose
- 4 g/day
RCTOmega-3 fatty acid supplements and risk of atrial fibrillation and 'micro-atrial fibrillation': A secondary analysis from the OMEMI trial2023n=70
A 2-year secondary analysis study examining 1014 patients (75% without AF history) with a recent myocardial infarction found that 1.8 g/day EPA/DHA supplementation led to increases in atrial fibrillation (AF) or micro-AF compared to a corn oil placebo (11.9% omega-3 vs 6.5% placebo). The change in serum EPA but not DHA largely mediated the effect, with higher serum EPA levels more predictive of atrial fibrillation or micro-AF. [10595]
- Effect
- No Benefit
- Dose
- 1.8 g/day
- Population
- Atrial fibrillation patients
- Participants
- 70
- Ages
- 70–82
Do Fish Oil Supplements Reduce A-Fib?2022
A review evaluated whether fish oil supplements reduce atrial fibrillation risk, summarizing available clinical evidence on omega-3 supplementation and AF incidence.
ObservationalHabitual fish oil supplementation and the risk of incident atrial fibrillation: findings from a large prospective longitudinal cohort study2022n=468,665
A prospective cohort analysis of 468,665 subjects without baseline atrial fibrillation (AF) from the UK Biobank cohort found an association between habitual fish oil supplementation and the risk of developing atrial fibrillation, even after controlling for genetic AF predisposition and dietary oily fish intake. At a median follow-up time of 11.1 years, fish oil users had an higher risk of AF (6.2% vs 5.2%) compared to non-users. In subjects with high genetic AF risk, fish oil users had a higher rate of incident AF (9.7% vs 8.1%). [10596]
- Effect
- No Benefit
- Participants
- 468,665
MetaEffect of Long-Term Marine ɷ-3 Fatty Acids Supplementation on the Risk of Atrial Fibrillation in Randomized Controlled Trials of Cardiovascular Outcomes: A Systematic Review and Meta-Analysis2021n=2,905
A systematic review of 4049 records and meta-analysis of 7 studies, with a median follow up of at least 1 year and minimum sample size of 500 patients was conducted with 81,210 patients. It was found after an average of 4.9 years, that omega-3 fatty acid supplements were associated with an increased risk of atrial fibrillation (>1 g/d HR, 1.49 & ≤1 g/d HR, 1.12) especially at doses exceeding 1 gram per day. [10597]
- Effect
- No Benefit
- Dose
- 1 g/day
- Population
- Cardiovascular patients
- Participants
- 2,905
- Avg age
- ~65
RCTEffect of Marine Omega-3 Fatty Acid and Vitamin D Supplementation on Incident Atrial Fibrillation: A Randomized Clinical Trial2021n=6,296
A study involving 24,127 participants aged 50 years or older without prior atrial fibrillation, cardiovascular disease or cancer randomly assigned participants either EPA-DHA and vitamin D (460 mg/day EPA, 380 mg/day DHA, 2000 IU/day D3), EPA-DHA and placebo, vitamin D3 and placebo, or 2 placebos. It found that after a median of 5.3 years treatment, there was no significant effect on the risk of incident AF but supplementation with both EPA-DHA (hazard ratio 1.09, P = 0.19) and vitamin D (hazard radio 1.09, P = 0.19) trended towards increased incident AF risk. [10598]
- Effect
- No Benefit
- Dose
- 460 mg/day
- Population
- Adults
- Participants
- 6,296
- Avg age
- ~50
RCTEffect of omega-3 fatty acids on cardiovascular outcomes: A systematic review and meta-analysis2021n=149,051
A meta-analysis of 38 RCTs and 149,051 participants given either EPA or EPA + DHA therapy found that EPA was more effective than combined therapy for improving cardiovascular outcomes and reducing cardiovascular mortality. EPA + DHA increased incident AF (RR 1.26) whilst EPA was associated with a higher risk of total bleeding and AF (RR 1.35) compared to placebo. Many studies included in this meta-analysis were manufacturer-funded. [10600]
- Effect
- No Benefit
- Population
- Adults
- Participants
- 149,051
MetaOmega-3 fatty acids supplementation and risk of atrial fibrillation: an updated meta-analysis of randomized controlled trials2021
A meta-analysis of 5 studies found that omega-3 supplementation was linked to an increased risk of atrial fibrillation in patients with elevated plasma triglycerides and those with elevated cardiovascular risk. [10599]
- Effect
- No Benefit
- Population
- Atrial fibrillation patients
RCTEffect of High-Dose Omega-3 Fatty Acids vs Corn Oil on Major Adverse Cardiovascular Events in Patients at High Cardiovascular Risk: The STRENGTH Randomized Clinical Trial2020n=6,539
A 2020 study found that 4 g/day omega-3 (Epanova, discontinued) taken for up to five years was associated with an increased risk for atrial fibrillation (2.2% vs 1.3%; HR, 1.69 [95% CI, 1.29-2.21]; nominal P < .001) compared to corn oil placebo. There were no significant differences with regards to new-onset heart failure or venous thromboembolic events (0.41% vs 0.26%; HR, 1.62; nominal P = .12). [10594]
- Effect
- No Benefit
- Dose
- 4 g/day
- Population
- Women
- Participants
- 6,539
RCTOmega-3 Polyunsaturated Fatty Acid (Fish Oil) Supplementation and the Prevention of Clinical Cardiovascular Disease: A Science Advisory From the American Heart Association2017
An AHA science advisory reviewed RCT evidence on fish oil for cardiovascular disease prevention, recommending omega-3 supplementation for secondary prevention in certain high-risk groups while noting limited primary-prevention data.
- Population
- Diabetic patients
RCTFish oil for the reduction of atrial fibrillation recurrence, inflammation, and oxidative stress2014n=337
A study of 337 patients (also not taking conventional antiarrhythmic therapy) with symptomatic paroxysmal or persistent atrial fibrillation within the 6 months prior to the study found that 4 g/day fish oil did not reduce either the time to first symptomatic or asymptomatic AF recurrence lasting more than 30 seconds. [10601]
- Effect
- No Benefit
- Duration
- 271 days
- Dose
- 4 g/day
- Population
- Atrial fibrillation patients
- Participants
- 337
RCTA randomized controlled trial to prevent post-operative atrial fibrillation by antioxidant reinforcement2013n=203
In 203 on-pump cardiac surgery patients, combined n-3 fatty acids 2 g/day plus vitamins C and E reduced postoperative atrial fibrillation to 9.7% versus 32% with placebo (p<0.001).
- Effect
- Benefit
- Dose
- 2 g/day
- Population
- Adults
- Participants
- 203
MetaFish oil and atrial fibrillation after cardiac surgery: a meta-analysis of randomized controlled trials2013n=2,687
A meta-analysis of 8 RCTs (2,687 cardiac surgery patients) found perioperative fish oil did not significantly reduce postoperative atrial fibrillation (RR 0.86, 95% CI 0.71–1.03) or hospital stay.
- Effect
- No Benefit
- Dose
- 1 g/day
- Population
- Adults
- Participants
- 2,687
MetaFish oil and post-operative atrial fibrillation: a meta-analysis of randomized controlled trials2013
A meta-analysis of randomized trials assessed whether perioperative fish oil reduces post-operative atrial fibrillation after cardiac surgery.
MetaFish oil increase the risk of recurrent atrial fibrillation: result from a meta-analysis2013
A meta-analysis of 8 RCTs with 1990 persistent AF and post-cardioversion patients found that short-term fish oil supplementation of less than 4 weeks prior to cardioversion did not reduce the risk of recurrent atrial fibrillation following cardioversion and slightly increased atrial fibrillation risk. However, longer term supplementation of at least 4 weeks before cardioversion decreased the absolute risk of recurrent atrial fibrillation compared to placebo. [10602]
- Effect
- No Benefit
MetaA meta-analysis of omega-3 fatty acids and incidence of atrial fibrillation2012
A meta-analysis of 11 RCTs found that fish oil did not have a significant effect on the risk of atrial fibrillation (Odds ratio 0.79, 95% confidence interval = 0.56-1.12, p = 0.19). [10603]
- Effect
- No Benefit
Regulation by interleukin-3 of human monocyte pro-inflammatory mediators. Similarities with granulocyte-macrophage colony-stimulating factor2012
An in vitro study found IL-3 stimulated monocyte u-PA and, with IFN-gamma, TNF-alpha production, showing selective pro-inflammatory mediator regulation similar in part to GM-CSF.
MetaDo omega-3 fatty acids prevent atrial fibrillation after open heart surgery? A meta-analysis of randomized controlled trials2011n=538
A meta-analysis of 4 RCTs (538 cardiac surgery patients) found perioperative n-3 PUFA supplementation did not significantly reduce postoperative atrial fibrillation, with conflicting trial results noted.
- Effect
- No Benefit
- Population
- Atrial fibrillation patients
- Participants
- 538
- Avg age
- ~62
RCTLong-term omega-3 polyunsaturated fatty acid supplementation reduces the recurrence of persistent atrial fibrillation after electrical cardioversion2011n=87
An open-label, randomised study of 178 cardioversion patients with persistent atrial fibrillation (> 1 month duration) found that 6 g/day fish oil reduced AF recurrence with or without concurrent antiarrhythmic drugs. Patients took fish oil for an average of 56 days precardioversion and a total of 242 days in follow up. At 90 days, the fish oil group had a 39% reduced risk of recurrent atrial fibrillation compared to placebo. [10605]
- Effect
- Benefit
- Duration
- 1 year
- Dose
- 6 g/day
- Population
- Atrial fibrillation patients
- Participants
- 87
MetaPrevention of atrial fibrillation with omega-3 fatty acids: a meta-analysis of randomised clinical trials2011n=1,955
A meta-analysis of 10 studies with 1955 patients found that omega-3 supplementation did not have any significant effects on the risk of atrial fibrillation. [10604]
- Effect
- No Benefit
- Population
- Adults
- Participants
- 1,955
Observationaln-3 Fatty acids consumed from fish and risk of atrial fibrillation or flutter: the Danish Diet, Cancer, and Health Study2005n=949
In 47,949 Danish adults followed 5.7 years, higher fish-derived n-3 intake showed no consistent linear association with atrial fibrillation or flutter risk across quintiles.
- Effect
- No Benefit
- Population
- Atrial fibrillation patients
- Participants
- 949
- Avg age
- ~56
ObservationalFish intake and risk of incident atrial fibrillation2004n=4,815
In 4,815 adults ≥65 followed 12 years, eating tuna or baked fish 1–4 times/week lowered incident AF risk 28% (HR 0.72) and ≥5 times/week lowered it 31% (HR 0.69) versus less than monthly intake.
- Effect
- Benefit
- Population
- Older adults
- Participants
- 4,815
- Ages
- 65+
Milk ThistleView supplement →
Reconsider purchase·★★★★★
How we scored this▸
- It’s not clear if milk thistle helps prevent atrial fibrillation (irregular heartbeat) after heart bypass surgery.
- One study found that taking silymarin, a component of milk thistle, 400 mg per day for three days before surgery reduced the risk of irregular heartbeat afterward.
- Because this was only one small study at a single hospital, the results need more confirmation.
Browse 1 study
RCTThe Effect of Silymarin on the Prevention of Atrial Fibrillation After Coronary Artery Bypass Grafting2024n=160
An RCT of 160 coronary artery bypass patients found preoperative silymarin 400 mg/day reduced postoperative atrial fibrillation (14 vs 30 patients) vs no silymarin.
- Effect
- Benefit
- Dose
- 400 mg/day
- Population
- Adults undergoing coronary artery bypass grafting
- Participants
- 160
- Ages
- 65–74
Vitamin DView supplement →
Do not purchase·★★★★★
How we scored this▸
- It is not clear if taking vitamin D supplements helps prevent atrial fibrillation, a common irregular heart rhythm.
- A large study in healthy adults showed that taking vitamin D daily for about five years did not lower the chance of developing atrial fibrillation compared to not taking vitamin D. However, some research in older adults and people with low vitamin D levels suggests that taking vitamin D might lower the risk of atrial fibrillation, especially in men over 65 with high blood pressure or diabetes.
- In these groups, having vitamin D levels in the healthy range after supplementation was linked to fewer cases of atrial fibrillation.
Browse 3 studies
ObservationalEffects of Vitamin D Supplementation and 25-Hydroxyvitamin D Levels on the Risk of Atrial Fibrillation2022n=39,845
In 39,845 vitamin D–deficient adults without prior AF, achieving 25(OH)D >20 ng/mL with ≥6 months treatment was associated with lower atrial fibrillation risk.
- Effect
- Benefit
- Duration
- 6 months
- Population
- Adults
- Participants
- 39,845
RCTEffect of Marine Omega-3 Fatty Acid and Vitamin D Supplementation on Incident Atrial Fibrillation: A Randomized Clinical Trial2021n=6,296
In VITAL (25,119 adults, 2000 IU/day vitamin D3, median 5.3 years), vitamin D did not reduce incident atrial fibrillation versus placebo (HR 1.09).
- Effect
- No Benefit
- Dose
- 2000 IU/day
- Population
- Adults
- Participants
- 6,296
- Avg age
- ~50
ObservationalVitamin D and bisphosphonates therapies for osteoporosis are associated with different risks of atrial fibrillation in women: A nationwide population-based analysis2018n=20,788
In 20,788 Taiwanese women with osteoporosis, vitamin D therapy was associated with lower new atrial fibrillation incidence than bisphosphonates or no treatment over 5 years.
- Effect
- Benefit
- Duration
- 1 year
- Population
- Women
- Participants
- 20,788
CaffeineView supplement →
Do not purchase·★★★★★
How we scored this▸
- Taking caffeine after heart surgery does not seem to help prevent abnormal heart rhythms, such as atrial fibrillation.
- In a study of patients who had surgery with a heart-lung machine, those who took high doses of caffeine (400 mg every 8 hours, about the amount in 4 cups of coffee each time) for several doses did not have fewer heart rhythm problems.
- In fact, the study was stopped early because people given caffeine had more side effects like nausea and vomiting, without any benefit for preventing heart rhythm issues.
Browse 1 study
RCTPeri-operative oral caffeine does not prevent postoperative atrial fibrillation after heart valve surgery with cardiopulmonary bypass: A randomised controlled clinical trial2018n=10
In 110 heart valve surgery patients, peri-operative oral caffeine 400 mg every 8 hours for 2 days did not prevent postoperative atrial fibrillation (33% vs 29%) and increased nausea/vomiting versus placebo.
- Effect
- No Benefit
- Duration
- 2 days
- Dose
- 400 mg/day
- Population
- Adults undergoing heart valve surgery
- Participants
- 10
Evidence visualised
Same ratings as above, aggregated so you can see coverage and imbalance.