The Impact of Obesity in Atrial Fibrillation
The Impact of Obesity in Atrial Fibrillation
Joy Stepinski, MSN, RN-BC
October 2, 2025
Atrial fibrillation is an abnormal heart rhythm caused by quivering of the upper chambers, or atria, of the heart. Normally, the two atria receive blood from the lungs or the body. When the atria contract, blood flows from the upper chambers to the lower heart chambers, or ventricles. In atrial fibrillation, the quivering prevents blood from flowing properly. As a consequence, there are risks for complications, including stroke. Research findings contribute to the growing body of literature investigating the relationship between atrial fibrillation (AF) and excess fat.
According to the Centers for Disease Control and Prevention (CDC), AF is the most common type of heart arrhythmia [1]. The lack of coordination between the upper chambers and the lower chambers causes the heart to beat too slowly, too fast, and irregularly. In an irregular rhythm, the heart’s even rhythmic tempo is lacking. For some people, AF may be a brief episode, but for others, the condition may be longstanding. Symptoms include heart palpitations, shortness of breath, fatigue, chest pain, and lightheadedness.
The CDC lists risk factors and diagnoses related to AF that are associated with lifestyle. These include high blood pressure, diabetes, heart failure, kidney disease, smoking, obstructive sleep apnea, and alcohol. Obesity is the central thread interconnected to all of these conditions and has been historically linked with atrial fibrillation.
One meta-analysis published in 2008 investigated the relationship between obesity and AF. Sixteen studies were used that enrolled a total of 123,249 participants [2]. Part of the research examined population-based cohorts, groups of people selected from the general population. Of these studies, subjects with obesity according to body mass index (BMI) showed a 49% increased risk of developing AF.
In a newer study, published in 2025, the authors examined the relationship between epicardial fat and AF [3]. Because BMI does not consider fat directly located around the heart, researchers scrutinized this association, known as epicardial adipose tissue (EAT). The study included 2,200 participants aged 40 and older from the Copenhagen General Population Study, which tracked health outcomes in the general population of Copenhagen, Denmark [4]. Researchers used a special type of imaging called CT angiography to measure the quantity of fat surrounding the outer surface of the heart muscle, known as epicardial fat volume.
The study outcomes showed that participants with a higher amount of fat surrounding the heart had twice the risk of developing AF compared to those with lower fat. The authors concluded that the location of fat in proximity to the heart directly plays a role in the development of AF.
Why is this so important? Fat stored deep within the body, known as visceral fat, surrounds internal organs. It plays an important role in cushioning organs, storing energy, and producing hormones to regulate metabolism. Visceral fat participates in the immune response by triggering inflammation that serves to protect vital organs in the presence of infection. However, too much visceral fat can lead to consequences that cause a higher risk for diabetes and metabolic syndrome. Additionally, people can experience poorer outcomes in cardiovascular disease [5], like AF.
Several mechanisms contribute to AF with respect to EAT, which is specific to the visceral fat that surrounds the heart. Chronic inflammation can cause remodeling of the atria, leading to stiffening of the muscle fibers [6]. Because the heart muscle is located in proximity to EAT, fat deposits in the atria can disrupt the heart’s normal rhythm. Not only does the heart pump less efficiently, but its electrical system is affected, leading to arrhythmias like AF.
The good news is that addressing lifestyle factors, particularly obesity, can decrease the presence and risk of AF [7]. One study demonstrated that AF severity and symptoms decreased when weight loss was greater than or equal to 10%. Participants included 1,415 patients with AF. Of those subjects, 825 began with a BMI ≥ 27 kg/m2. Some symptomatic patients (45.5%) no longer required medication or an ablation. An ablation is a treatment that aims to destroy the heart tissue causing the abnormal beats. Maintaining weight loss can lead to a 6-fold greater chance of the patient being free from AF.
Specific to visceral adipose tissue, a separate study showed that diet can reduce internal fat. The study enrolled 294 participants, who were randomly assigned to Healthy Dietary Guidelines (HDG), Mediterranean diet, or green-Mediterranean diet [8]. The HDG diet consisted of basic health-promoting foods, while the Mediterranean diet included calorie-restricted Mediterranean foods. The green-Mediterranean group was asked to consume 3-4 cups of green tea daily, more plant food, and avoid red processed meat. Results concluded that the green-Mediterranean diet doubled the amount of visceral adipose tissue loss.
Other lifestyle factors may improve AF. For example, one meta-analysis concluded that exercise reduces EAT [9]. An article focusing on lifestyle medication in improving or preventing AF suggested the following [10]. Diets should encompass mostly plants. Incorporating 150 minutes weekly of moderate exercise and yoga improves activity because being sedentary is associated with AF. Other physiological and emotional factors include getting sufficient sleep, managing stress, improving mood, and quitting smoking. Furthermore, some chronic diseases like diabetes and COPD place patients at a higher risk of AF. Lifestyle interventions can help reduce the risks of these conditions.
Decisions surrounding the prevention and treatment of AF are important considerations. The irregular heart rhythm can lead to stroke and other complications. Medications are not without risk. Addressing lifestyle factors to reduce weight and improve health provides options with little harm.
References:
Centers for Disease Control and Prevention. (2024). About Atrial Fibrillation. https://www.cdc.gov/heart-disease/about/atrial-fibrillation.html?CDC_AAref_Val=https://www.cdc.gov/heartdisease/atrial_fibrillation.htm
Wanahita, N., Messerli, F. H., Bangalore, S., Gami, A. S., Somers, V. K., & Steinberg, J. S. (2008). Atrial fibrillation and obesity—results of a meta-analysis. American Heart Journal, 155(2), 310-315. https://doi.org/10.1016/j.ahj.2007.10.004
Pedersen, J. J., Kühl, J. T., Elming, M. B., Pham, M. H. C., Sigvardsen, P. E., Nordestgaard, B. G., ... & Kofoed, K. F. (2025). Epicardial adipose tissue and new-onset atrial fibrillation in a Danish cohort. European Heart Journal, ehaf515.
McKnight, P. (2025). More heart fat linked to greater risk for atrial fibrillation. Medscape Medical News. https://www.medscape.com/s/viewarticle/more-heart-fat-linked-greater-risk-atrial-fibrillation-2025a1000mrv?_gl=1*16tjb2l*_gcl_au*NTI4MDMxNDY2LjE3NTkwMTIxOTI
Poggi, A. L., Gaborit, B., Schindler, T. H., Liberale, L., Montecucco, F., & Carbone, F. (2022). Epicardial fat and atrial fibrillation: the perils of atrial failure. EP Europace, 24(8), 1201-1212.
Conte, M., Petraglia, L., Cabaro, S., Valerio, V., Poggio, P., Pilato, E., ... & Parisi, V. (2022). Epicardial adipose tissue and cardiac arrhythmias: focus on atrial fibrillation. Frontiers in Cardiovascular Medicine, 9, 932262. https://doi.org/10.3389/fcvm.2022.932262
Pathak, R. K., Middeldorp, M. E., Meredith, M., Mehta, A. B., Mahajan, R., Wong, C. X., ... & Sanders, P. (2015). Long-term effect of goal-directed weight management in an atrial fibrillation cohort: A long-term follow-up study (LEGACY). Journal of the American College of Cardiology, 65(20), 2159-2169. https://doi.org/10.1016/j.jacc.2015.03.002
Zelicha, H., Kloting, N., Kaplan, A., Yaskolka Meir, A., Rinott, E., Tsaban, G., ... & Shai, I. (2022). The effect of high-polyphenol Mediterranean diet on visceral adiposity: the DIRECT PLUS randomized controlled trial. BMC medicine, 20(1), 327.
Colonetti, T., Grande, A. J., Amaral, M. C., Colonetti, L., Uggioni, M. L., da Rosa, M. I., ... & Roever, L. (2021). Effect of exercise on epicardial adipose tissue in adults: a systematic review and meta-analyses. Heart Failure Reviews, 26(6), 1399-1411.
Hynes, M. (2021). Beyond ablation in atrial fibrillation: 10 steps to better control. American Journal of Lifestyle Medicine, 15(4), 434-440.