Omega-3 fatty acids, found mostly in oily fish and fish oil supplements, have long been touted as beneficial for cardiovascular health, with claims that the nutrient can reduce bad cholesterol levels and improve heart function. Now a new study published in the journal Circulation finds that a certain type of fatty acid often present in fish docosahexaenoic acid (DHA) may actually work to prevent the occurrence of atrial fibrillation, a heart rhythm abnormality especially common in older people that can lead to stroke and heart failure.
Unlike most dietary research, which relies on questionnaires that are prone to errors of self-reporting, the current study actually took blood samples from its more than 3,300 participants over age 65 to obtain a more accurate measure of the amount of fish oil they were consuming. After following the participants for over 14 years, researchers from the Harvard School of Public Health found that those in the top quartile of omega-3 blood levels were about 30 percent less likely to develop atrial fibrillation, compared to adults in the bottom quartile.
Atrial fibrillation is the most common type of heart arrhythmia, affecting up to nine percent of U.S. adults. However, most cases go largely undiagnosed, making prevention even more important. Thus, as ACSH's Dr. Gilbert Ross notes, A 30 percent reduced risk of atrial fibrillation, perhaps linked to higher amounts of DHA consumption, is impressive. More Americans should be following the U.S. Department of Agriculture guidelines by consuming fish at least twice weekly.