Eicosapentaenoic acid (EPA) is an omega-3 fatty acid. It is a polyunsaturated fatty acid with 20 carbon atoms. The human body cannot efficiently produce EPA, classifying it as an essential fatty acid that must be obtained through diet or supplementation.
Dietary and Supplemental Sources
Individuals can obtain EPA through various natural dietary sources. Fatty fish, such as salmon, mackerel, herring, sardines, and tuna, are rich in EPA. Beyond fish, certain types of algae also serve as direct sources of EPA, providing a vegetarian option for intake.
While some plant-based foods, like flaxseed, soybean, and canola oils, contain alpha-linolenic acid (ALA), the body’s conversion of ALA to EPA is very limited, typically less than 15%. This low conversion rate makes direct sources of EPA more significant for adequate intake. Supplemental forms, such as fish oil and algal oil, are common options for those who do not consume enough EPA through their diet.
How EPA Supports Health
A significant function is its anti-inflammatory properties, which are achieved by inhibiting pro-inflammatory eicosanoids. EPA competes with arachidonic acid, reducing the production of molecules that promote inflammation, and also contributes to the formation of specialized pro-resolving lipid mediators that aid in resolving tissue injury and inflammation.
This anti-inflammatory action extends to cardiovascular health, where EPA helps manage triglyceride levels. It significantly reduces blood triglyceride concentrations, a benefit observed with daily intakes of 2 grams of EPA + DHA for blood triglyceride levels. EPA also supports blood vessel function by enhancing endothelial function, which improves blood vessel relaxation and blood pressure regulation.
Beyond its direct effects on lipids, EPA may reduce arterial stiffness, a factor correlated with cardiovascular disease. It also helps prevent excessive blood clotting, thereby reducing the risk of conditions like heart attacks and strokes. Studies indicate that EPA can reduce atherosclerotic plaque formation and progression, making plaques less likely to trigger clinical events.
EPA also contributes to brain health and cognitive function. Adequate levels of EPA, alongside DHA, are fundamental for optimal brain function, influencing neuronal membranes and overall cognitive processes. While DHA is often highlighted for brain development, EPA appears more influential on behavior and mood.
Research suggests that EPA may play a role in mood regulation, with studies indicating benefits in major depressive disorder and bipolar disorder. It also supports general cellular health and membrane integrity, as omega-3s are important components of the membranes surrounding every cell in the body.
Important Considerations for EPA Intake
When considering increasing EPA intake, general guidelines suggest a balanced dietary approach. The U.S. Food and Drug Administration advises a combined intake of no more than 5 grams per day of EPA and DHA from dietary supplements. For individuals with heart disease, the American Heart Association recommends about 1 gram per day of EPA plus DHA, preferably from oily fish, or supplements under medical guidance.
Mild side effects from EPA supplementation can occur, including an unpleasant taste, bad breath, heartburn, nausea, stomach discomfort, or diarrhea. Taking EPA with meals may help reduce these digestive issues.
EPA can interact with certain medications, particularly those affecting blood clotting. High doses, especially above 3 grams daily, might slow blood clotting and increase the risk of bruising and bleeding, especially if taken with anticoagulant or antiplatelet drugs like warfarin. It can also slightly lower blood pressure, potentially enhancing the effects of blood pressure-lowering medications.
Given these potential interactions and individual health variations, consulting a healthcare professional is advisable before starting any new supplement regimen. This is particularly important for individuals with underlying health conditions, those taking other medications, or pregnant and nursing individuals. A healthcare provider can offer personalized advice on appropriate dosages and monitor for any potential adverse effects or interactions.