I hesitate to call this a "diet" book because it is so much more than that. A better word would be a "die" book. This book teaches more fully than perhaps any other (outside the Bible, of course) how to truly "die" to oneself. Although 2 different eating plans are described in the book, the meat of the book trains the reader to "feast" on Jesus and His Word and to "drink" from the Living Waters. It is astounding just how much of Scripture deals with this topic.
If you are wanting to lose some weight or overcome any other besetting sin in your life, I would recommend checking this out. Unfortunately, the Setting Captives Free website was disbanded at the beginning of October (unclear why), but this book and the companion teacher's guide are still available.
I put today's date as the date I finished the book, but I intend to keep reading it over and over.