Diet and Atrial Fibrillation: What You Eat Matters

Introduction:

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia, affecting millions worldwide. While medications and procedures like catheter ablation are crucial in managing AF, lifestyle and dietary choices play a significant role in both preventing and managing this condition. As a cardiologist, I often get asked: "Can what I eat really affect my heart rhythm?" The answer is a resounding yes. Recent research highlights how certain diets and dietary components can either increase or decrease the risk of AF. In this blog post, we’ll dive into the latest evidence on how diet impacts AF, separating fact from fiction, and providing practical advice for both general practitioners and patients.

Summary of Key Findings:

Positive Studies: Diets and Components That May Reduce AF Risk

1. Mediterranean Diet:

   • A secondary analysis of the PREDIMED trial showed that a Mediterranean diet enriched with extra virgin olive oil reduced the risk of new-onset AF by 38% compared to a control diet.

   • Ongoing studies like PREDIMAR are exploring its effects on recurrent AF post-ablation

     
     

2. Alcohol Reduction:

   • Randomized controlled trials (RCTs) have shown that reducing alcohol intake significantly decreases AF burden and recurrence. For example, a study found that reducing alcohol consumption by nearly eight-fold over six months led to longer freedom from recurrent AF.

   • Large cohort studies also suggest that even low levels of alcohol consumption (≥1 drink per week) may increase AF risk, especially in men and beer drinkers.

     
     

3. Vitamin C:

   • Several small RCTs suggest that perioperative oral vitamin C supplementation, especially when combined with other therapies, may lower the incidence of post-operative AF.

   • A meta-analysis of 13 RCTs found that vitamin C combined with other therapies reduced post-operative AF risk by 68%.

     
     

4. n-3 Polyunsaturated Fatty Acids (PUFAs):

   • Short-term n-3PUFA supplementation has been shown to reduce post-operative AF risk, particularly when combined with vitamins C and E.

   • However, long-term, high-dose n-3PUFA supplementation may increase the risk of new-onset AF, as seen in the STRENGTH trial.

     
     

Negative Studies: Diets and Components That May Increase AF Risk or Show No Benefit

1. Ultra-Processed Foods:

   • Higher consumption of ultra-processed foods was linked to an increased risk of new-onset AF in a large prospective cohort study (HR 1.13, 95% CI 1.02–1.24).

     
     

2. Caffeine/Coffee:

   • Despite being a commonly reported trigger for AF, most prospective cohort studies show no overall association between caffeine/coffee intake and new-onset AF risk. In fact, some studies suggest a U-shaped relationship, with moderate coffee consumption (4–5 cups/day) associated with the lowest AF risk.

     
     

3. Chocolate:

   • While some studies suggest a modest reduction in AF risk with moderate chocolate consumption, others, including the Women’s Health Study and Physicians’ Health Study, found no association between chocolate intake and AF risk.

     
     

4. Vitamin D:

   • The VITAL Rhythm study, the largest RCT on vitamin D, found no significant difference in new-onset AF risk with vitamin D supplementation compared to placebo.

   • However, some studies suggest that vitamin D supplementation before cardiac surgery may reduce post-operative AF risk.

     
     

5. Magnesium:

   • While some RCTs suggest that oral magnesium supplementation may reduce post-operative AF risk, a meta-analysis of 20 RCTs found no association between intravenous magnesium supplementation and post-operative AF risk.

     
     

Conclusion:

The relationship between diet and atrial fibrillation is complex, but the evidence is clear: what you eat can influence your heart rhythm. While no single diet has been definitively proven to prevent AF, certain dietary patterns like the Mediterranean diet, especially when enriched with extra virgin olive oil, show promise in reducing AF risk. On the other hand, diets high in ultra-processed foods and excessive alcohol consumption are associated with increased AF risk.

As always, it’s important to tailor dietary recommendations to individual patient needs and preferences. Future research will hopefully provide more clarity on the role of diet in AF prevention and management. In the meantime, adopting a heart-healthy diet rich in whole foods, lean proteins, and healthy fats, while minimizing processed foods and alcohol, is a safe and effective strategy for both patients and practitioners.

This blog post aims to empower both general practitioners and patients with actionable insights into how diet can influence atrial fibrillation, helping them make informed decisions for better heart health.

Link for further reading: Monika Gawałko, Melissa E Middeldorp, Arnela Saljic, John Penders, Thomas Jespersen, Christine M Albert, Gregory M Marcus, Christopher X Wong, Prashanthan Sanders, Dominik Linz, Diet and risk of atrial fibrillation: a systematic review, European Heart Journal, Volume 45, Issue 40, 21 October 2024, Pages 4259–4274