Most 65-year-old women benefit from 1,000 to 2,000 mg of combined EPA and DHA per day, the two active omega-3 fats in fish oil. There is no single official recommendation because the ideal amount depends on what you’re trying to support: general wellness, heart health, brain function, or something else. The FDA caps supplement labels at 2,000 mg of EPA plus DHA daily, which serves as a practical upper guideline for most people without a prescription.
Why There’s No Single “Right” Dose
The Institute of Medicine never set a specific daily intake level for EPA and DHA, so you won’t find a universal recommendation the way you would for, say, vitamin D or calcium. Instead, dosage guidance comes from medical organizations targeting specific health concerns. The American Heart Association recommends about 1,000 mg per day of EPA plus DHA for people with existing heart disease, and up to 4,000 mg per day (prescription strength) for lowering very high triglycerides. For general health, most evidence points to a range of 1,000 to 1,500 mg daily as a reasonable target.
When shopping for fish oil, pay attention to the EPA and DHA numbers on the label, not the total fish oil amount. A capsule labeled “1,000 mg fish oil” might contain only 300 mg of EPA and DHA combined. You may need two or three capsules to reach a meaningful dose.
Heart Health at 65
Heart disease is the leading concern for women in this age group, and the research here is mixed but worth understanding. The large VITAL trial, which enrolled adults aged 50 and older, found that 1,000 mg of omega-3s daily did not significantly reduce the overall rate of major cardiovascular events like heart attacks, strokes, and cardiac death when looking at the entire study group. But the details tell a more nuanced story.
Among all participants, omega-3 supplementation was linked to a 28% reduction in heart attacks specifically. For people who ate little fish before the trial, that reduction jumped to 40%. And for people with two or more heart disease risk factors, such as smoking or high blood pressure, the reduction reached 44%. Omega-3s did not, however, affect stroke risk in this trial. A separate trial using a much higher dose of 4,000 mg daily in high-risk patients found a 25% reduction in major cardiovascular events including both heart attacks and strokes, though that dose requires a prescription.
Brain and Memory Benefits
Cognitive decline is a real concern at 65, and this is where dosage matters more than you might expect. A large meta-analysis of omega-3 and cognitive function found a dose-dependent relationship: benefits for memory didn’t clearly emerge until doses exceeded 1,000 mg per day. The optimal range for the most consistent cognitive effects was between 1,000 and 2,500 mg per day, with no adverse effects reported within that window.
Global cognitive performance improved with doses up to about 1,500 mg per day, then declined at higher amounts. Attention and language abilities followed a similar pattern, peaking around 1,500 mg daily before leveling off. Memory, on the other hand, showed a more linear relationship, continuing to improve at doses above 1,000 mg. The takeaway: if brain health is your primary motivation, aim for at least 1,000 mg of combined EPA and DHA, and the sweet spot appears to be around 1,500 mg per day.
Bone and Joint Considerations
Postmenopausal women face accelerated bone loss, so it’s natural to wonder whether fish oil helps. The evidence here is modest. A systematic review of ten randomized controlled trials found that omega-3 fatty acids on their own did not consistently improve bone mineral density. However, when omega-3s were combined with calcium supplements, several studies showed meaningful benefits, including improved bone density at the hip and spine. One study in postmenopausal women with osteoporosis found that a combination of omega-3s and calcium maintained lumbar spine density and increased femoral neck (hip) density compared to a control group.
If you’re taking fish oil partly for bone health, pairing it with adequate calcium intake appears to be important. Fish oil alone is unlikely to move the needle on bone density.
Dry Eye Relief
Dry eye becomes increasingly common with age and affects women more than men. Studies have tested a range of omega-3 doses for dry eye symptoms, from about 500 mg to 3,000 mg of combined EPA and DHA per day. The largest and most rigorous trial used 2,000 mg of EPA and 1,000 mg of DHA daily (3,000 mg total) in patients with moderate dry eye. Other studies showing benefit used around 1,680 mg of EPA and 560 mg of DHA. If dry eye is your main reason for considering fish oil, doses in the 2,000 to 3,000 mg range have been most commonly studied, though this pushes above the FDA’s 2,000 mg supplement label guideline and is worth discussing with your eye doctor.
Fish Oil, Krill Oil, or Algal Oil
Standard fish oil delivers EPA and DHA in a form called triglycerides. Krill oil delivers them partly as phospholipids, which are the same type of fat that makes up your cell membranes. This structural difference may improve absorption. In one crossover trial, krill oil doubled the increase in a key blood marker of omega-3 status (the omega-3 index) compared to the same dose of fish oil. Another study found higher plasma levels of EPA and DHA after krill oil, though the difference didn’t quite reach statistical significance.
That said, not all studies agree. One trial giving similar amounts of EPA from krill oil and standard fish oil found nearly identical absorption. The research is still limited and uses different doses and durations, making direct comparisons tricky. Krill oil capsules are smaller and may be easier to swallow, but they cost more per milligram of EPA and DHA. Algal oil is the main plant-based alternative and provides DHA (and sometimes EPA), making it a reasonable option for people who avoid animal products or have fish allergies.
Side Effects and How to Minimize Them
The most common side effects of fish oil are digestive: burping, fishy aftertaste, and loose stools. These are annoying but not dangerous. You can reduce them by taking fish oil immediately before a meal rather than on an empty stomach, and by avoiding carbonated drinks at the same time. Enteric-coated capsules, which dissolve in the intestine rather than the stomach, also help with fishy burps. Freezing regular capsules before taking them can have a similar effect.
At higher doses, fish oil has a mild blood-thinning effect. It reduces platelet clumping by replacing a pro-clotting fatty acid in platelet membranes with EPA and DHA, which are less prone to triggering clots. For most people this is harmless or even beneficial, but if you take blood thinners like warfarin, the combination has been flagged as a potential interaction. A retrospective study of patients on warfarin found that fish oil did not significantly affect clotting measurements or increase adverse events in practice, but it’s still something to mention to your prescriber so they can monitor if needed.
A Practical Starting Point
For a 65-year-old woman looking for broad benefits across heart, brain, and overall health, 1,000 to 1,500 mg of combined EPA and DHA per day covers the range supported by the strongest evidence. That typically means two to three standard fish oil capsules daily, depending on the product’s concentration. Look for supplements that list EPA and DHA content separately on the label, and add those two numbers together to find your actual dose. If you’re targeting a specific condition like very high triglycerides or moderate dry eye, the effective doses studied are higher and worth discussing with a healthcare provider to determine what’s appropriate for your situation.