Cleveland Clinic study links gut bacteria byproduct to irregular heartbeat risk

Could what you eat affect your heart rhythm? New research led by Cleveland Clinic suggests it might.

Researchers have found that higher blood levels of TMAO, a compound produced when gut bacteria digest nutrients found in red meat and other animal products, are associated with a greater risk of developing atrial fibrillation, the most common type of irregular heartbeat.

The study, published in the Journal of Clinical Investigation, analyzed blood samples from more than 5,000 people undergoing heart procedures. Researchers also conducted laboratory studies and found that TMAO appears to change the heart’s electrical environment, making it more susceptible to abnormal rhythms.

Atrial fibrillation, often called AFib, affects at least 2.7 million Americans. Symptoms can include fatigue, heart palpitations, shortness of breath and dizziness. Left untreated, AFib can increase the risk of stroke.

“Most current treatments for atrial fibrillation focus on managing the condition, but our findings suggest there may be an opportunity to intervene much earlier through diet,” said lead researcher Dr. Robert Koeth, an electrophysiologist with Cleveland Clinic’s Miller Family Heart, Vascular & Thoracic Institute.

The findings build on more than a decade of Cleveland Clinic research exploring the connection between the gut microbiome and heart health. Previous studies have linked elevated TMAO levels to a higher risk of heart attacks, strokes and chronic kidney disease.

Researchers say the study identifies a promising target for future prevention, but it does not prove that eating red meat directly causes atrial fibrillation. Instead, it highlights the growing role the gut microbiome may play in cardiovascular health.