Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia associated with a two-fold increase in mortality caused by a higher risk of stroke and heart failure. Currently, AF is present in ~ 2 % of the general population, and its incidence and prevalence are increasing. Obesity, hypertension, diabetes mellitus, obstructive sleep apnea, and alcohol consumption increase the risk of AF. Each unit of increase in BMI increases the risk of AF by 3 %, and intensive weight loss is also associated with reduced AF recurrence. Hypertension increases the risk of AF by 50 % in men and by 40 % in women, and explains ≈ 20 % of new AF cases. Patients with obstructive sleep apnea are at four times higher risk of developing AF than subjects without sleep apnea. Higher concentrations of pro-inflammatory cytokines, higher amounts of epicardial adipose tissue, and a higher degree of ventricular diffuse myocardial fibrosis are present in AF patients and patients with the aforementioned metabolic disorders. Several prospective cohort studies and randomized trials have been initiated to show whether weight loss and treatment of other risk factors will be associated with a reduction in AF recurrences.