This is a valuable book that can be read and reread over the course of his work. Fasting is wrongly surrounded by an austere image, see deprivation. This book makes him acclaim. He explains in a clear and detailed manner the interests of the fast, how to start, drive and finally break it. Each phase is very clear, this book is an indispensable tool to get started. It also details the precautions which medical monitoring for fasting days. The benefits of fasting are far more numerous than the difficulty in driving it.