A new study published in Circulation showed that fish oil, omega-3s, did not increase perioperative bleeding in surgery patients. In fact, higher blood omega-3 levels were associated with lower risk of bleeding. For this study, 1516 patients scheduled for cardiac surgery were randomized to omega-3s or placebo. The dose was 6.5-8 grams of EPA+DHA over 2 to 5 days before surgery, and then 1.7 grams per day beginning on the morning of surgery and continuing until discharge.
Surprisingly, there was a significant reduction in the number of units of blood needed for transfusions. In another analysis, the higher the blood EPA+DHA level on the morning of surgery, the lower the risk for bleeding. “The researchers in this study concluded that these findings support the need to reconsider current recommendations to stop fish oil or delay procedures for people on fish oil before cardiac surgery,” said Bill Harris, PhD. “In other words, bleeding in surgery (and in normal life) is not a safety concern for omega-3 supplements.”