Evening primrose oil is a rich source of omega-6 essential fatty acids. Evening primrose oil contains linoleic acid as well as GLA - both are essential components of myelin, the protective coating around nerve fibers, and the neuronal cell membrane. Increase bone density in elderly people with osteoporosis. Used for skin disorders such as eczema, psoriasis, and acne. Women use evening primrose oil in pregnancy for preventing high blood pressure (pre-eclampsia), shortening labor, starting labor, and preventing late deliveries