Eicosapentaenoic acid

Eicosapentaenoic acid (EPA) is a 20-carbon omega-3 fatty acid with five double bonds. It occurs mainly in marine foods and serves as a precursor to lipid signaling molecules.

Arachidonic acid: A 20-carbon omega-6 fatty acid that is a precursor to many lipid signaling molecules. It competes with EPA in membrane lipids and supplies related signaling pathways.
Fatty acid: A carboxylic acid with a hydrocarbon chain, commonly serving as a component of lipids. EPA is a long-chain fatty acid.
Fish oil: Oil extracted from the tissues of oily fish, commonly containing EPA and DHA. Fish oil is a widely used dietary source of EPA.
Omega-6 fatty acid: A polyunsaturated fatty acid with its first double bond at the sixth carbon from the methyl end. Omega-6 fatty acids have a different double-bond position and often share metabolic pathways with EPA.
Phytoplankton: Microscopic photosynthetic organisms that drift in aquatic environments. Marine phytoplankton synthesize EPA and form a foundation for its movement through food webs.
Eicosanoids: Signaling molecules derived from polyunsaturated fatty acids that act locally in tissues. EPA is converted into eicosanoids that can influence inflammation, blood flow, and clotting.
Polyunsaturated fatty acid: A fatty acid whose hydrocarbon chain contains at least two carbon–carbon double bonds. EPA’s five double bonds place it in this structural family.
Omega-3 fatty acid supplements: Products supplying omega-3 fatty acids, often as fish oil, algal oil, or purified compounds. Supplement formulations use EPA alone or alongside DHA.
Krill oil: Oil extracted from small marine crustaceans, containing omega-3 fatty acids largely in phospholipid form. It is an alternative marine source of EPA, with a different lipid composition from fish oil.
Marine food web: The network of feeding relationships among organisms in marine ecosystems. EPA passes through marine food webs from microscopic producers into fish and other seafood.

Linked from 6 pages

Essential fatty acidRelated: Its limited production illustrates the metabolic constraints on the omega-3 pathway.