According to research reviewed by Gram, higher levels of the omega-3 fat EPA stored in body fat were linked to a 36% lower risk of bleeding stroke over 21 years. The Danish study of 54,546 adults found the link was consistent for men and women. Researchers suggest that diet, not only total omega-3 intake, may matter.
According to research reviewed by Gram, people with higher levels of the omega-3 fat EPA stored in their body fat had a lower risk of bleeding strokes over about 21 years. Bleeding strokes happen when a blood vessel in or around the brain ruptures. Researchers in Denmark studied more than 54,546 adults aged 50 to 65 and measured omega-3 levels in fat tissue taken at the start of the study. Those in the top fifth for EPA had about 36% lower odds of a bleeding stroke than those in the bottom fifth. A fat called ALA was linked to higher risk. This study cannot prove that EPA causes the lower risk, but it adds useful evidence about how these fats relate to brain health. Fat tissue reflects what people have eaten over many months or years, not just last week.
Key Statistics
A 2026 Danish case-cohort study of 54,546 adults aged 50 to 65 found that people with the highest EPA levels in body fat had a 36% lower risk of hemorrhagic stroke compared with those with the lowest levels.
The same 2026 study reported that high ALA levels in body fat were associated with a 32% higher risk of hemorrhagic stroke, while DHA and combined EPA plus DHA levels showed no statistically significant link.
Over a median follow-up of 21 years, researchers identified 729 hemorrhagic stroke cases among participants in the Danish Diet, Cancer and Health Cohort.
The Quick Take
- What they studied: The researchers asked whether the amounts of certain omega-3 fats stored in body fat are linked to the chance of having a bleeding stroke. They looked at several omega-3 fats, with the strongest focus on EPA, which is found mainly in fatty fish.
- Who participated: The study followed 54,546 men and women from Denmark who were 50 to 65 years old when they joined between 1993 and 1997. Researchers measured omega-3 levels in fat tissue for all 729 people who later had a bleeding stroke and for a random group of 4,615 other participants.
- Key finding: People in the top fifth for EPA in body fat had a 36% lower chance of a bleeding stroke than people in the bottom fifth (hazard ratio 0.64, meaning roughly two-thirds the risk). The result was statistically significant, so it is unlikely to be due to chance alone. Higher ALA levels were linked to about 32% higher risk.
- What it means for you: Eating fatty fish regularly is a well-established part of a heart-healthy diet, and this study suggests it may also be connected to lower bleeding stroke risk. This is one observational study, so it does not prove that eating more fish prevents strokes. Talk with your doctor before starting fish oil supplements, since high-dose omega-3 supplements can affect bleeding.
The Research Details
This was a case-cohort study, a design that follows a large group of people over time and compares those who develop a disease with a smaller, randomly chosen group. The study used the Danish Diet, Cancer and Health Cohort, which recorded participants’ health and lifestyle starting in the 1990s.
At the start, researchers took small samples of fat tissue from participants. They then measured the types and amounts of omega-3 fats in those samples using a lab method called gas chromatography. Fat tissue is useful because it stores fats over long periods, so it gives a picture of typical intake over months to years rather than a single meal.
Cases of bleeding stroke were identified by matching study records with the Danish National Patient Register, a national database of hospital visits and diagnoses. Participants were followed for a median of 21 years, and the researchers used statistical models that account for differences in age, sex, and other health factors.
Measuring fat tissue, rather than relying only on food questionnaires, gives a more objective view of long-term omega-3 intake. People often misreport what they eat, so a lab measurement helps reduce that error. Following people for more than two decades also allows enough time for strokes to occur and be recorded. The case-cohort design makes it practical to study a very large group without measuring every participant’s fat tissue.
Strengths include a large sample, a long follow-up period, objective lab measurements, and national health records that capture strokes reliably. The researchers also checked whether results differed for men and women and for different stroke types. However, this is an observational study, so it can show links but cannot prove cause and effect. The study was published in a peer-reviewed journal, which means outside experts reviewed it before publication. Readers should still treat the findings as one piece of a larger body of evidence.
What the Results Show
The main finding was that higher EPA levels in fat tissue were linked to a lower risk of bleeding strokes overall. Comparing the top fifth of EPA levels with the bottom fifth, the risk was about 36% lower (hazard ratio 0.64, with a 95% confidence range of 0.50 to 0.82). The confidence range is narrow and stays below 1, which supports the idea that the link is real in this group rather than random noise.
The pattern was similar for men and women. When researchers looked at bleeding stroke types, the link held for intracerebral (bleeding inside the brain) hemorrhage, while results for subarachnoid hemorrhage (bleeding in the space around the brain) were not statistically significant. This could be due to fewer cases of that type, which makes it harder to detect a true effect.
Not all omega-3 fats showed the same pattern. DHA, DPA, and the combined total of EPA plus DHA were not significantly linked to bleeding stroke risk. Meanwhile, high levels of ALA, a plant-based omega-3 found in flaxseed, chia, and walnuts, were linked to a higher risk, with the top fifth showing about 32% higher risk than the bottom fifth (hazard ratio 1.32).
These results suggest that the type of omega-3 fat matters, not just the total amount of omega-3 in the body. The researchers conclude that EPA and ALA appear to have different relationships with bleeding stroke, and more research is needed to explain why.
The researchers checked several subgroups, and the overall pattern stayed consistent across men and women, which adds confidence that the finding is not limited to one sex. The lack of a clear result for subarachnoid hemorrhage is important: it shows the link is not uniform across all stroke subtypes, and it points to the need for larger studies to examine rarer stroke types.
The finding about ALA is also worth noting. Many people eat plant-based omega-3 sources for heart health, so a link between high ALA and higher bleeding stroke risk is unexpected and calls for further investigation. It does not mean that flaxseed or walnuts are harmful, because the study measured fat tissue levels, which may reflect many factors beyond diet alone.
Earlier research has often linked omega-3 fats from fish with lower risk of heart attacks and clotting-related heart disease. This study extends that work to bleeding strokes, which are less common than clot-related strokes and have been studied less. The EPA finding fits with the general view that fish-derived omega-3s support blood vessel health.
At the same time, some clinical trials of high-dose omega-3 supplements have raised questions about a small increase in bleeding or atrial fibrillation in certain groups. This study does not contradict those findings, because it looked at natural levels in fat tissue from diet rather than high-dose supplements. Together, the evidence suggests that moderate intake from food is the safer and better-supported path for most people.
Because this was an observational study, it cannot prove that EPA causes lower bleeding stroke risk. People with higher EPA levels may differ in other ways, such as eating more fish, exercising more, or having different income or health habits, even though the researchers adjusted for many factors.
The study measured omega-3 levels only once, at the start. Fat tissue reflects long-term intake, but it does not show how diets changed during the 21 years of follow-up. The study also included only Danish adults aged 50 to 65, so results may not apply to younger people or to populations with very different diets.
Bleeding strokes are relatively rare, and some subtypes had fewer cases, which limits how precise the estimates are for those groups. Finally, the results do not tell us how much EPA is ideal or whether taking supplements would have the same effect as getting EPA from food.
The Bottom Line
Eating fatty fish such as salmon, sardines, or mackerel about twice a week is widely recommended for heart health, and this study adds a modest reason to keep doing so (moderate confidence). Eating more ALA sources like flaxseed or walnuts is a reasonable part of a balanced diet, but this study does not show they are protective against bleeding stroke (low confidence). Taking high-dose omega-3 supplements to lower stroke risk is not supported by this study alone (low confidence), and anyone on blood thinners or with bleeding concerns should check with a doctor first.
Adults over 50 who want to support heart and brain health through diet may find this research especially relevant. People who already eat fish regularly do not need to change much based on this study alone. People taking blood thinners, those with a history of bleeding problems or stroke, and anyone considering high-dose fish oil should talk with a healthcare provider before making changes. People who follow strict plant-based diets may also want to consult a professional about getting adequate EPA and DHA.
Changes in fat tissue omega-3 levels reflect eating patterns built up over months to years, so benefits, if any, would be expected only after sustained dietary habits. Because stroke risk is shaped by many factors over decades, it is not realistic to expect a noticeable change in stroke risk within weeks. Most people should think of this as a long-term habit rather than a quick fix.
Frequently Asked Questions
Does EPA omega-3 lower the risk of bleeding stroke?
A 2026 Danish cohort study found that people with the highest EPA levels in body fat had a 36% lower risk of bleeding stroke than those with the lowest levels. The study is observational, so it shows an association rather than proof that EPA causes the lower risk.
Which foods contain EPA omega-3?
EPA is found mainly in fatty fish such as salmon, sardines, mackerel, and herring. Eating these fish about twice a week is widely recommended for heart health. Plant sources like flaxseed and walnuts contain ALA, a different omega-3 that this study linked to higher bleeding stroke risk.
Should I take fish oil supplements to prevent bleeding stroke?
This study does not support starting fish oil supplements specifically to prevent bleeding stroke. Research measured natural fat tissue levels, not high-dose supplements. High doses can affect bleeding, so people on blood thinners or with bleeding concerns should consult a doctor before taking them.
What is the difference between EPA and ALA omega-3s?
EPA comes mostly from fatty fish, while ALA comes from plant foods like flaxseed, chia, and walnuts. In this Danish study, higher EPA levels in body fat were linked to lower bleeding stroke risk, while higher ALA levels were linked to higher risk, showing that omega-3 types may act differently.
Want to Apply This Research?
- Log the number of servings of fatty fish (such as salmon, sardines, or mackerel) eaten each week, using one serving as about 3 ounces cooked. Set a measurable goal, such as two servings per week, and track whether you meet it each week.
- Add one fatty fish meal per week, such as salmon on salad or sardines on whole-grain toast, and replace a less healthy protein choice. Use the app’s reminder feature to plan fish meals on the same days each week so the habit becomes automatic.
- Review your weekly fish servings monthly and look for consistency over three to six months. Pair this with routine checkups where your doctor reviews blood pressure, cholesterol, and any medications that affect bleeding, and record any supplement use in the app so it can be discussed at appointments.
This article summarizes an observational study and is for general education only. It does not provide medical advice, diagnosis, or treatment. Observational research can show associations but cannot prove that a nutrient causes a health outcome. Do not start, stop, or change any supplement or medication based on this article. Consult a qualified healthcare provider, especially if you take blood thinners, have a history of stroke or bleeding disorders, or have other health conditions.
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.