Confused about the relationship between different fatty acids and their functions and food sources? Here's a quick guide:
Alpha-Linolenic Acid: the "parent" omega-3 fatty acid. Found in flaxseeds, hempseeds, pumpkin seeds, walnuts, and dark green leafy vegetables. Flaxseed oil is the richest source, containing almost 60 percent alpha-linolenic acid.
EPA: a derivative of alpha-linolenic acid. Needed to make hormonelike substances called prostaglandins that are anti-inflammatory in nature. Found in fish liver oil supplements and cold-water fish, such as salmon, trout, and tuna.
DHA: another derivative of alpha-linolenic acid. Necessary for proper brain and nervous system development and visual function. Found in cold-water fish and fish liver oil supplements. Also available in vegetarian supplements made from microalgae.
Linoleic Acid: the "parent" omega-6 fatty acid. Makes primarily proinflammatory prostaglandins but also some anti-inflammatory prostaglandins. Found in high amounts in vegetable oils and in small amounts in most plant foods, such as sesame seeds, pumpkin seeds, and many nuts.
Gamma-Linolenic Acid: a derivative of linoleic acid. Makes more anti-inflammatory prostaglandins than proinflammatory prostaglandins. Found in evening primrose oil, borage oil, and black currant oil.