In another strike against fish oil supplements for cardiac health, taking omega-3 fatty acid before heart surgery did not help prevent a common irregular heart rhythm called atrial fibrillation, according to research in the Journal of the American Medical Association.
The study included over 1,500 people in the United States, Italy, and Argentina who were slated for heart surgery. Atrial fibrillation happens in one-third of people after cardiac surgery, and previous research suggested that omega-3 fatty acids in fish oil might prevent this irregular rhythm.
Two days before surgery, study participants were chosen at random to take either 1-gram capsules of fish oil containing 840 mg of omega-3s, or an identical capsule with no fish oil. They continued taking two capsules per day after surgery until they left the hospital.
The supplements didn’t help. The number of men who had periods of atrial fibrillation lasting more than 30 seconds were virtually identical: 30% of men taking the placebo fish oil pill versus 31% of those taking the real thing. This adds to the evidence that fish oil supplements may not help to prevent cardiovascular disease.