Many people with atrial fibrillation (AF) are told to avoid coffee, assuming caffeine triggers arrhythmias. The DECAF randomized clinical trial in JAMA tested this directly in 200 adults with persistent AF undergoing cardioversion. Over 6 months, AF/atrial flutter recurred less often in the caffeinated coffee group than in the abstinence group (47% vs 64%), with a lower hazard of recurrence and no significant difference in adverse events. This article explains the study in plain language, why the results matter, who should still be cautious, and how Doctors365 online consultations can help you personalize your trigger and lifestyle plan safely.

1.1 Educational disclaimer + authorship

This article is for educational purposes only and is not a substitute for medical advice, diagnosis, or emergency care. If you think you may be experiencing a medical emergency, seek urgent help immediately.

Author: Dr. Diellza Rabushaj
Medically reviewed by: Dr. Spec Orhan Karahodza

Coffee has been blamed for atrial fibrillation (AF) flare-ups for years—so much so that many people with AF feel they should quit, even when they love their morning cup. But what if that “coffee = trigger” idea isn’t universally true? The DECAF randomized clinical trial finally put this question to a real test in people with persistent AF after cardioversion. [1]

1.2 Why this question matters for people living with AF

AF is a common heart rhythm disorder, and many patients actively look for lifestyle changes that might reduce recurrences. Coffee is one of the most widely used caffeinated beverages, so even small effects could matter for daily life and long-term care decisions. [1]

2. The DECAF Trial in Plain English

2.1 Who was studied

DECAF enrolled 200 adults (average age about 69, 71% men) with persistent AF (or atrial flutter with a history of AF) who were scheduled for electrical cardioversion at 5 hospitals across the US, Canada, and Australia. [1]

2.2 What “coffee group” vs “abstinence group” actually did

After successful cardioversion, participants were randomized for 6 months to either:

• Caffeinated coffee consumption: encouraged to drink at least 1 cup daily (or 1 espresso shot), without intentionally increasing/decreasing beyond usual habits.
• Abstinence: encouraged to avoid all coffee (including decaf) and other caffeine-containing products. [1]

2.3 What counts as an AF recurrence in this trial

The primary outcome was clinically detected AF or atrial flutter lasting ≥30 seconds, confirmed by clinician-interpreted ECG evidence (standard ECG, wearable ECG, or implanted device data). [1]

3. The Headline Result: Good News for Coffee Lovers

3.1 Recurrence rates (47% vs 64%)

Over 6 months, AF/atrial flutter recurrence occurred in:

• 47% of the coffee-consumption group
• 64% of the abstinence group [1]

3.2 The hazard ratio explained without math anxiety

The researchers reported a hazard ratio of 0.61—meaning the coffee group had about a 39% lower hazard (risk over time) of recurrence compared with the abstinence group. If hazard ratios feel abstract, imagine two runners on a track: over the same time window, the “recurrence runner” reached the finish line less often in the coffee group. [1]

3.3 Safety findings

Importantly, no significant difference in adverse events was observed between groups during follow-up (including outcomes like hospitalization, emergency visits, stroke/TIA, or death—within the limits of the trial size). [1]

4. Why Might Coffee Help? Theories, Not Guarantees

4.1 Caffeine and adenosine (the “doorbell” analogy)

One proposed pathway involves adenosine receptors. The trial authors discuss how typical caffeine levels can block A1/A2a receptors, and adenosine may help facilitate AF under certain conditions. Think of adenosine like a doorbell that can help start unwanted “electrical visitors.” Caffeine may dampen that doorbell signal in some contexts. This is a biologically plausible idea—but it’s still a mechanism hypothesis, not a personal guarantee. [1]

4.2 Inflammation, activity, and other lifestyle ripple effects

Coffee contains many compounds beyond caffeine, and the authors note potential anti-inflammatory links and behavioral effects. They also reference prior research where coffee assignment was associated with more daily steps in another trial, and physical activity can be relevant to AF management. Again: plausible, interesting, not definitive. [1]

4.3 Why this doesn’t mean “more caffeine = better”

DECAF studied typical coffee intake (roughly averaging 1 cup/day during follow-up in the coffee group). The authors explicitly caution against extrapolating these findings to high-dose caffeine or synthetic caffeine products (like some energy drinks), which may contain additional ingredients and different dosing patterns. [1]

5. Who Should Still Be Careful With Caffeine

5.1 If coffee feels like your trigger

Even though the trial challenges the blanket “coffee is pro-arrhythmic” assumption, the authors acknowledge the possibility that some individuals may truly be sensitive. If you consistently notice palpitations or AF episodes soon after coffee, that pattern deserves a personalized plan. [1]

5.2 Sleep, anxiety, reflux, and blood pressure considerations

Coffee can affect sleep, and poor sleep can worsen how people feel day-to-day with AF. Coffee can also aggravate reflux or anxiety-like symptoms in some people, which can mimic or amplify palpitations. These “indirect effects” matter when you’re deciding what’s right for you. (DECAF focused on AF recurrence—not overall symptom comfort in every scenario.) [1]

6. Practical Takeaways If You Have AF

6.1 A reasonable “coffee plan” to discuss with your clinician

Based on DECAF, for people with AF who already drink coffee, it may be reasonable to discuss a plan like:

• Keep coffee steady and moderate (for example, around 1 cup/day)
• Track symptoms and rhythm data if you use a wearable
• Reassess if episodes cluster around caffeine timing [1]

6.2 What not to do (energy drinks, megadoses, sudden changes)

• Don’t treat this as a reason to start high-dose caffeine. [1]
• Don’t swap coffee for energy drinks (different dosing, additives). [1]
• Don’t make abrupt changes if you’re sensitive to withdrawal or if routine shifts affect sleep—talk it through first. [1]

7. How Doctors365.org Works

Getting help online should feel simple:

1. Browse specialists (start here: doctors)
2. Pick a time that suits you
3. Confirm & pay
4. Join a secure online visit
5. Receive a visit summary and next steps (and prescriptions when clinically appropriate)

8. Benefits of Online Cardiology Advice Through Doctors365

When you’re juggling AF meds, triggers, and lifestyle changes, quick guidance can be a relief:

• Convenience: talk from home—especially helpful if you’re monitoring symptoms.
• Privacy: discuss sensitive concerns comfortably.
• Continuity: review your rhythm history, cardioversion plan, and lifestyle questions in one place.

CTA: If you want a cardiology-focused review of your AF triggers and daily habits, book here:

9. Quality & Trust: What to Look for in a Telehealth Visit

When choosing online care for AF questions, look for:

• Verified clinicians and clear credentials
• Clinical governance (structured standards for care quality)
• Secure communication and strong data protection practices

10. What’s Appropriate Online vs In-Person

10.1 Online is often appropriate for

• “Should I stop coffee or keep it?” discussions using evidence like DECAF [1]
• Medication review and side-effect check-ins
• Reviewing wearable rhythm trends and symptom diaries

10.2 Seek urgent in-person care for red flags

Get urgent help if you have:

• Chest pain, severe shortness of breath, fainting, or new severe weakness
• Stroke warning signs (face droop, arm weakness, speech difficulty)
• Rapid worsening symptoms or feeling unsafe at home

11. Pricing & Availability

Pricing varies by specialty and clinician availability. You’ll typically see the cost before checkout when you book. Start browsing and choose a time that works for you:

12. Featured Doctors365 Specialists

12. Featured Doctors365 Specialists

• Dr Andreas Mussigbrodt MD — Leipzig-based cardiologist & internist with deep expertise in arrhythmias and invasive electrophysiology; multilingual care.
• Dr William Novick — Cardiologist with training listed at Graduate Hospital (Philadelphia) and the University of Alabama.
• Dr Carlos Van Mieghem — Cardiologist with education at Erasmus University Rotterdam and experience noted at OLV Hospital Aalst and KU Leuven.
• Dr Christos Varounis — Cardiologist with education listed at Athens University (Medical School) and experience including echocardiography and major Athens-area hospitals.
• Dr Stojan Mitreski — Cardiologist with experience across international centers, including Clinical Centre “Dedinje” (Belgrade) and a cardiovascular medicine center in Ohrid.
• Dr Petar Pekic — Internal medicine specialist & cardiology subspecialist focused on arrhythmias and cardiac device implantation/follow-up.
• Dr AlaaEldin Y. Alhessi — Senior consultant cardiologist with interventional cardiology experience, including cardiac catheterization and patient management.
• Dr Walid Shibl Ibrahim — Alexandria-based cardiologist with 20+ years’ practice and a strong focus on echocardiography and cardiovascular diagnostics.

13.1 Should everyone with AF start drinking coffee now?

Not automatically. DECAF suggests coffee may be reasonable for many coffee drinkers with AF, but decisions should be individualized. [1]

13.2 Did coffee increase complications or hospitalizations?

The trial did not find a significant difference in adverse events between groups over 6 months, but it wasn’t powered for rare outcomes. [1]

13.3 How much coffee did participants drink?

The coffee group averaged about 1 cup/day during follow-up (median around 7 cups/week). [1]

13.4 Does this apply to energy drinks or high caffeine supplements?

No. The authors caution against extrapolating these findings to high-dose or synthetic caffeine products. [1]

13.5 What if I’m sure coffee triggers my AF?

Personal patterns matter. Even with reassuring trial data, if coffee reliably triggers symptoms for you, discuss tailored options with a clinician. [1]

14. Conclusion

For years, many people with AF have heard “coffee is bad for your rhythm.” The DECAF randomized trial delivers a refreshingly different message: among prior coffee drinkers with persistent AF after cardioversion, caffeinated coffee consumption was associated with fewer recurrences than caffeine abstinence, without a clear signal of harm in the measured adverse events. [1]

If you want help turning this evidence into a realistic plan (coffee timing, sleep, wearables, meds, and triggers), book a consultation.
Prefer to start broader and choose the right specialty for your situation? Browse all clinicians here:

References

1. Wong CX, Cheung CC, Montenegro G, et al. Caffeinated coffee consumption or abstinence to reduce atrial fibrillation: the DECAF randomized clinical trial. JAMA. 2026;335(4):317-325. doi:10.1001/jama.2025.21056. Published online November 9, 2025.
2. Written by Diellza Rabushaj,MD, Medical Writer & Researcher.