I don't know if everything in this book is true, or not, but a goodly portion of it seems to be, based on my own experience. This book instructs the reader in how to examine the external condition of their body in order to determine what is going on internally. As an example, I've found its claims about chapped lips to be true, in that lip-chapping generally seems to indicate a digestive problem. And I've found that when I clear up the digestive issue, the lips stop chapping. So I've learned to watch that very carefully.