DESC: Evening Primrose Oil contains gamma linolenic acid (GLA), an essential fatty acid that assists the body in producing prostaglandins (messengers in the body that perform hundreds of important functions). Without an adequate supply of GLA, optimal health is impossible to achieve. Each capsule provides 40 mg of gamma-linolenic acid and 300 mg of linoleic acid, together with 15 IU of vitamin E as a protective antioxidant. Other beneficial oils - linoleic, oleic and palmitic - are contained in each 500 mg capsule.