New Insights from the REDUCE-IT Study
The REDUCE-IT trial, sponsored by Amarin and presented at the American College of Cardiology 2020 Scientific Session, changed the way experts look at omega-3 therapies. For years, the assumption was that omega-3 drugs worked primarily by lowering triglycerides.
But according to Dr. Deepak L. Bhatt, lead investigator and professor of medicine at Harvard Medical School, the real driver of cardiovascular protection in REDUCE-IT was achieved EPA blood levels — not changes in triglycerides, LDL, or CRP.
Patients who reached higher EPA levels in their blood experienced striking reductions in:
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Heart attack and stroke
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Cardiovascular deaths
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Hospitalizations for unstable angina
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Sudden cardiac arrest
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Need for stenting or bypass procedures
This discovery marks a turning point, similar to the early days of statin research.
What Is Icosapent Ethyl (Vascepa)?
Icosapent ethyl (brand name Vascepa) is a purified prescription form of EPA. In REDUCE-IT, over 8000 high-risk patients already on statins were randomized to receive either 4 grams per day of icosapent ethyl or placebo.
Over nearly five years, the study found:
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25% reduction in first major cardiovascular events
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30% reduction in total events (first + subsequent)
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Significant protection even when patients were already on therapies such as aspirin, beta-blockers, ACE inhibitors, and statins
The takeaway: EPA added protection above and beyond standard care.
Why EPA Levels Matter More than Triglycerides
One of the most revealing findings was that the benefit remained independent of baseline EPA levels (dietary fish intake or genetics). What mattered most was the EPA concentration achieved during treatment.
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Patients in the highest EPA tertile had the lowest risk of cardiovascular events and death.
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EPA levels rose by nearly 400% on treatment.
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DHA levels, meanwhile, actually fell slightly — suggesting that the effect was unique to EPA.
Dr. Bhatt concluded: “The higher the EPA level in the blood, the lower the cardiovascular risk.”
Supplements, Diet, and Prescription EPA — What’s the Difference?
EPA levels achieved in REDUCE-IT were far beyond what diet or standard omega-3 supplements typically provide. Dr. Bhatt explained that to match these levels with over-the-counter fish oil, one would need to swallow 20–30 capsules daily, often containing mixtures of EPA, DHA, and other fats.
That said, omega-3 supplements and a seafood-rich diet are still valuable, especially for people who don’t meet criteria for prescription Vascepa. EPA and DHA from high-quality fish oils remain essential for maintaining an optimal Omega-3 Index (8–12%), a proven protective zone for heart health.
Personalized Omega-3 Intake: The Role of the Omega-3 Index
Whether you use diet, supplements, or prescription therapy, one fact is clear: blood levels matter most.
The Omega-3 Index — a measure of EPA and DHA in red blood cells — is now widely recognized as a cardiovascular risk marker, validated by more than 200 studies. A protective Omega-3 Index (8–12%) is linked with:
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Lower cardiovascular disease risk
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Reduced sudden cardiac death
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Longer lifespan
Research from Drs. Bill Harris and Kristina Harris Jackson has shown that reaching this zone usually requires 1–2 grams of EPA+DHA daily, depending on baseline levels and formulation type (triglyceride vs. ethyl ester).
Conclusion: A New Era in Omega-3 Science
The REDUCE-IT trial proves that it’s not just about taking omega-3s — it’s about achieving meaningful EPA blood levels. Prescription EPA like Vascepa achieves these levels in high-risk patients, but supplements and diet also play an important role for broader populations.
If you’re considering omega-3s for heart health, the first step is testing your Omega-3 Index. This simple blood test allows you to measure, modify, and monitor your status, helping you choose the right strategy to reach protective levels.
Omega-3 science is moving fast, but one message is clear: when it comes to heart health, your blood levels of EPA matter more than your triglyceride numbers.