Gamma-Lin 1300 is a dietary supplement to support skin & nerve health & premenstrual functional needs. Gamma-Lin is a pure, natural vegetable oil processed from the seeds of the Evening Primrose plant. Oil of Evening Primrose is 70% Linoleic Acid & is unique in providing a direct dietary source of the vital Gamma Linolenic Acid. Da Vinci Laboratories guarantees a minimum of 117 mg (9%) Gamma Linolenic Acid (GLA) per 1300 mg capsule & a minimum of 45 mg (9%) Gamma Linolenic Acid (GLA) per 500 mg capsule. Gamma Linolenic Acid (GLA) is converted by natural processes in the body to prostaglandins, which have a range of important functions such as regulation of brain function & the immune system.