Harvard Men's Health Watch

Fish oil does not prevent irregular heart rhythms after surgery

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.

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