 You might have a brain bleed, so please, please don't take omega-3 fatty acids. I recently talked to a patient who was on a blood thinner and she spoke to her cardiologist and the cardiologist yelled at her and said, no, you can't take omega-3 fatty acids. Well, here's reassuring news for users of omega-3s. Meta-analysis finds no increase in bleeding risk from omega-3s.