This book explores the traditional use of Ilex paraguariensis, a plant that is widely distributed in South America. Thanks to its purported properties, it has been used for centuries in the form of teas with a variety of names, including: ¿yerba mate¿ (Argentina), ¿chimarrãö (Brazil), and others. Ilex paraguariensis and its teas (also referred to as ¿mate teas¿) are well known because of their alleged pharmacological effects in numerous common conditions, including obesity, osteoporosis, constipation, arthritis, and hypertension. These effects are generally ascribed to yerba mate teas because the botanical species contains bioactive and stimulating substances like caffeine (originally dubbed ¿mateine¿), various alkaloids, and several phenolic