Eicosapentaenoic Acid (EPA) is a Polyunsaturated Omega-3 Fatty Acid and is involved in the regulation of inflammatory processes and prevention of blood clots.
Omega-3 fatty acids (omega-3s) have a carbon–carbon double bond located three carbons from the methyl end of the chain. Omega-3s, sometimes referred to as “n-3s,” are present in certain foods such as flaxseed and fish, as well as dietary supplements such as fish oil. Several different omega-3s exist, but the majority of scientific research focuses on three: alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA). ALA contains 18 carbon atoms, whereas EPA and DHA are considered “long-chain” (LC) omega-3s because EPA contains 20 carbons and DHA contains 22.
PUFAs are frequently designated by their number of carbon atoms and double bonds. ALA, for example, is known as C18:3n-3 because it has 18 carbons and 3 double bonds and is an n-3, or omega-3, fatty acid. Similarly, EPA is known as C20:5n-3 and DHA as C22:6n-3. Omega-6 fatty acids (omega-6s) have a carbon–carbon double bond that is six carbons away from the methyl end of the fatty acid chain. Linoleic acid (C18:2n-6) and arachidonic acid (C20:4n-6) are two of the major omega-6s.
The human body can only form carbon–carbon double bonds after the 9th carbon from the methyl end of a fatty acid. Therefore, ALA and linoleic acid are considered essential fatty acids, meaning that they must be obtained from the diet. ALA can be converted into EPA and then to DHA, but the conversion (which occurs primarily in the liver) is very limited, with reported rates of less than 15%. Therefore, consuming EPA and DHA directly from foods and/or dietary supplements is the only practical way to increase levels of these fatty acids in the body.
ALA is present in plant oils, such as flaxseed, soybean, and canola oils. DHA and EPA are present in fish, fish oils, and krill oils, but they are originally synthesized by microalgae, not by the fish. When fish consume phytoplankton that consumed microalgae, they accumulate the omega-3s in their tissues.
EPA
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