Vitamins F, essential fatty acids are composed of two fatty acids - linoleic acid (LA) and alpha-linoleic acid (LNA) - with linoleic acid being the most complete fatty acid. There are two basic categories of EFA's (essential fatty acids) - omega-3 and omega-6 which include linoleic acid and gamma-linoleic acid. The body is not capable of manufacturing essential fatty acids, while the fatty acid arachidonic acid can be synthesized in the body from linoleic acid.