Each Evening Primrose Oil softgel Capsule contains 500mg Evening Primrose Oil which contains Gamma-linolenic acid (GLA) and linoleic acid (LA). They are used by most cells in the body to produce the soothing intracellular hormonelike messengers, known as series 1 prostaglandins (PGE1), that help maintain the balance of many functions in the body. GLA and LA both support the immune system, help maintain healthy skin, and help maintain healthy circulation. These essential nutrients are incorporated into our cell membranes, where they help to maintain fluidity and permeability.