First published in 1910, this classic book is considered Ehret's health masterpiece. Complete instructions are given on how to successfully conduct and complete a fast in order to gain maximum strength and energy for joyful living. Ehret also presents his theories on the fundamental causes of disease and his treatise on the Definite Cure of Chronic Constipation. Also included are essays by Fred Hirsch, long-time student of Ehrets, and Teresa Mitchell.