Evening Primrose Oil is a rich, natural source of the unsaturated Omega-6 essential fatty acid - Gamma Linolenic Acid (GLA).Our Evening Primrose Oil capsule provides 1000mg of pure, cold-pressed Evening Primrose Oil. Cold pressing ensures that none of the valuable components of the oil are destroyed during processing and is vital to maintain the integrity of these with each capsule providing a guaranteed 8-10% GLA.