Natural Factors Certified Organic Oil of Oregano is derived from this wild-crafted Mediterranean species. The oil is extracted from the hand-picked leaves using gentle steam distillation to ensure potency and purity. Because pure oil of oregano is too potent to be used full strength, it is blended in a one-to-four ratio with organic, cold-pressed, extra-virgin olive oil. This is the ideal ratio for enabling the body to assimilate the oil of oregano.*.