Natural Factors Ultra Prim Evening Primrose Oil - 1000 mg - Ultra Prim is Ultra Refined Evening Primrose Oil in its purest form. Essential Fatty Acids are essential to the health of every cell in the body, and they are available only through diet or supplementation. Evening Primrose Oil is one of the few substances found in nature that is high in GLA, an EFA that is more advanced and ready for metabolism and assimilation by the human body. Maintaining proper levels of fatty acid intake has shown to reduce symptoms and problems associated with PMS and menopause. Relief of skin disorders and arthritis symptoms are also well documented. People suffering from heart disease, multiple sclerosis, obesity, diabetes, and even schizophrenia have all shown good results from Omega 6 fatty acid intake in clinical tests and studies.