Borage seed oil, contain 17-28% gamma-linolenic acid (GLA), the richest known source. The oil also contains the fatty acids palmitic acid (10-11%), stearic acid (3.5-4.5%), oleic acid (16-20%), linoleic acid (35-38%), eicosenoic acid (3.5-5.5%), erucic acid (1.5-3.5%), and nervonic acid (1.5%). The oil is often marketed as "starflower oil" or "borage oil" for use as a GLA supplement, although healthy adults will typically produce ample GLA from dietary linoleic acid.