(Source Naturals) Gamma-linolenic acid is an essential fatty acid and precursor of key hormones called PGE1 prostaglandins. These soothing hormones promote the fluidity of cellular membranes for proper nutrient absorption, brain function, skin health, and immune system support. Borage Seed Oil provides a high yield of GLA. Hexane-free. 240 mg. 2 month supply.