In 1211, Eisai wrote the first edition of the , the first Japanese treatise on tea. The "Kissa Yōjōki" promotes the drinking of tea for health purposes. It opens with the statement that "Tea is the most wonderful medicine for nourishing one's health; it is the secret of long life." The preface describes how drinking tea can have a positive effect on the five vital organs (a concept in traditional Chinese medicine). Eisai subscribed to a theory that the five organs each preferred foods with different flavors, and he concluded that because tea is bitter, and "the heart loves bitter things", it would especially benefit the heart. Eisai goes on to list the many purported health effects of tea, which include curing fatigue, lupus, indigestion, beriberi disease, heart disease, and so on, in addition to quenching thirst. The "Kissa Yōjōki" also explains the shapes of tea plants, tea flowers and tea leaves and covers how to grow tea plants and process tea leaves. The treatise says little regarding the drinking of tea for pleasure, however, focusing instead on its medicinal value.