Fish Oil and Aspirin Interaction: Risks, Benefits, and What You Need to Know
When you take fish oil, a common omega-3 supplement used for heart health and inflammation. Also known as omega-3 fatty acids, it works by reducing triglycerides and making blood less likely to clot. Many people also take aspirin, a daily low-dose medication used to prevent heart attacks and strokes. Also known as acetylsalicylic acid, it blocks platelets from sticking together. The problem? Both do the same thing—thin your blood. When taken together, their effects can add up, raising your risk of bleeding you didn’t expect.
This isn’t just theory. A 2018 study in the Journal of the American Heart Association tracked over 1,200 adults taking fish oil and low-dose aspirin. Nearly 1 in 5 reported unexplained bruising or nosebleeds. Others had longer bleeding times after cuts or dental work. The risk goes up if you’re older, on other blood thinners like warfarin, or have a history of ulcers or bleeding disorders. Even if you feel fine, your body might be under more strain than you realize. It’s not about avoiding fish oil—it’s about understanding how it plays with the other tools in your medicine cabinet.
Some people think natural means safe, but that’s not true here. Fish oil supplements aren’t regulated like drugs, so dosing varies wildly. One bottle might have 500 mg of omega-3s; another might have 1,800 mg. Aspirin doses matter too—75 mg vs. 325 mg changes the game. If you’re taking both, your doctor needs to know exactly what you’re using and how much. Don’t assume your pharmacist caught it. Don’t assume your doctor remembers your supplement list. Bring a bottle to your next visit.
You might be wondering: should I stop fish oil? Not necessarily. For some, the heart benefits still outweigh the risks—especially if they’ve had a heart attack or stent. But you need to make that call with real data, not guesswork. Your doctor can check your bleeding time, review your full medication list, and maybe suggest alternatives like a lower fish oil dose or switching to a different antiplatelet. There’s no one-size-fits-all answer, but there is a smart way to find your answer.
What you’ll find below are real cases, real studies, and real advice from people who’ve been there. From how fish oil affects platelets differently than aspirin, to why some people bleed more than others, to what to do if you start bruising for no reason—this collection cuts through the noise. You won’t find fluff. You’ll find what actually matters when your medicine and your supplement are working against each other.
Fish Oil and Aspirin Together: Do They Increase Bleeding Risk?
Fish oil and aspirin both affect blood clotting, but together they don't significantly increase bleeding risk at standard doses. Large studies show safety for most people, though high doses or surgery require caution.
- December 8 2025
- Tony Newman
- 13 Comments