Gamma-Linolenic acid (GLA) is an omega-6 essential fatty acid found primarily in vegetable oils. It is sold as a dietary supplement for treating inflammation and auto-immune diseases.
GLA was first isolated from the seed oil of evening primrose. This herbal plant was grown by Native Americans to treat swelling in the body.
GLA is obtained from vegetable oils, such as evening primrose (Oenothera biennis) oil, blackcurrant seed oil, borage oil and hemp seed oil, and from spirulina.
The human body produces GLA from linoleic acid (LA). While LA is consumed sufficiently in most diets (from cooking oils and meats), a deficiency can occur when the body lacks delta-6-desaturase--the enzyme that concerts it. This can happen as people grow older, when there are specific dietary deficiencies, or in disease states where there is excessive consumption of GLA metabolites.
From GLA, the body forms dihomo-gamma-linolenic acid (DGLA). This is one of the body's three sources of eicosanoids.
Yung-Sheng Huang, Vincent A. Ziboh (2001). Gamma-Linolenic Acid: Recent Advances in Biotechnology and Clinical Applications. AOCS Press, 259. ISBN 1893997170. Retrieved on 2007-12-07.