Omega-3 fatty acids—specifically EPA and DHA—are some of the most researched nutrients in cardiovascular medicine. While the REDUCE-IT, VITAL, and ASCEND studies were published over a year ago, the scientific insights they’ve yielded continue to influence clinical understanding and public health recommendations. Recent findings reaffirm the importance of omega-3s for heart health, particularly at higher doses.
Do High Doses of Omega-3s Slow Atherosclerosis?
A new study published in Nutrients conducted a systematic review and meta-analysis of randomized controlled trials to determine whether high-dose omega-3 intake reduces atherosclerosis. This review included studies like REDUCE-IT (Western populations using >3 g/day EPA+DHA) and Japanese studies with moderate dosing (~1.8 g/day), aiming for similar Omega-3 Index outcomes.
Results:
Researchers concluded that higher omega-3 intake was significantly associated with a slower progression of coronary and carotid artery disease. This adds to growing evidence that EPA and DHA may protect cardiovascular health by directly impacting the disease process in arterial walls.
Understanding the Omega-3 Index
The Omega-3 Index measures the levels of EPA and DHA in red blood cell membranes and is a strong predictor of cardiovascular risk. Proposed in 2004 as a marker for cardiovascular mortality, it is considered more reliable than plasma omega-3 levels.
-
A 1 standard deviation increase (2.1%) in the Omega-3 Index corresponds to a 15% lower risk of fatal coronary heart disease.
-
Increasing the Index from 4% (average US level) to 8% could translate to an estimated 30% risk reduction in fatal CHD.
For individuals who do not consume at least two servings of fish per week, researchers recommend omega-3 supplementation between 500 mg and 4,000 mg of EPA+DHA daily, especially for high-risk individuals and those with elevated triglyceride levels.
A Dose-Response Relationship in Cardiovascular Protection
A meta-analysis published in the Journal of the American Heart Association pooled data from 13 major trials, increasing the total study population to nearly 130,000 individuals. The outcomes measured included myocardial infarction, coronary heart disease death, total cardiovascular disease, and major vascular events.
Key Findings Over 5 Years:
-
3838 myocardial infarctions
-
3008 CHD deaths
-
15,759 cardiovascular events
-
16,478 major vascular events
Even excluding the REDUCE-IT trial, omega-3 supplementation was associated with significantly reduced risk of myocardial infarction, CHD death, and total CVD. Including REDUCE-IT further strengthened these associations and confirmed a linear dose–response relationship: the higher the omega-3 dose, the greater the cardiovascular benefit.
Omega-3 Blood Levels in REDUCE-IT
One lingering question has been: what Omega-3 Index did participants in REDUCE-IT actually achieve? A study in the Journal of Clinical Lipidology estimated these levels through two independent analyses:
-
Translating plasma EPA concentrations into red blood cell EPA estimates
-
Using published RBC data from similar short-term Vascepa studies
Findings showed baseline Omega-3 Index levels of ~5%, increasing to about 7% after supplementation with 4g/day EPA. This level was linked to a 25% reduced risk of cardiovascular events.
What to Expect from the STRENGTH Trial
Another major study, STRENGTH, is set to offer more clarity. Sponsored by AstraZeneca and using a combination EPA+DHA product (Epanova), this trial includes 50% more participants than REDUCE-IT. Researchers anticipate even higher Omega-3 Index levels due to the inclusion of DHA, which is known to elevate the Index more than EPA alone.
Depending on the outcome, the study may:
-
Confirm that a higher Omega-3 Index provides greater cardiovascular benefit
-
Suggest total omega-3 dose is the key factor
-
Spark debate about the specific roles of EPA vs DHA
The results of STRENGTH are expected to add important insights to this growing body of research.
Conclusion: Why Omega-3 Dose Matters
The collective findings from REDUCE-IT, VITAL, ASCEND, and other recent analyses make one thing clear: achieving and maintaining higher levels of EPA and DHA in the blood is critical for cardiovascular protection. Whether it's slowing the progression of atherosclerosis or reducing the risk of major cardiovascular events, omega-3 supplements—when taken at an effective dose—can play a powerful preventive role.
Support Your Heart with Ballstad Omega-3
If you’re not regularly consuming fish or have elevated cardiovascular risk, Ballstad Omega-3 can help you reach optimal blood levels of EPA and DHA. Our premium fish oil supplements are formulated to deliver high bioavailability and proven results—backed by science, trusted by health professionals.
