Eating too little or too much of fish may increase the risk of atrial fibrillation, or irregular heartbeat, Danish researchers say. Dr. Thomas Rix and colleagues from Aalborg University Hospital in Denmark found a U-shaped association between consumption of marine n-3 polyunsaturated fatty acids -- n-3 PUFA -- and the risk of developing atrial fibrillation, with people who have both low and high intakes found to suffer more from atrial fibrillation than those with median intakes. However, the study, presented at the European Heart Rhythm Association EUROPACE Congress in Athens found the lowest risk of atrial fibrillation was found in those who consumed about two servings of fatty fish per week. \"Since atrial fibrillation is present in more than 6 million people in Europe and associated with considerable morbidity, mortality and economic costs, preventing atrial fibrillation by achievable dietary changes would be of major public interest,\" Rix said in a statement.