So far as I know, the oldest in the English language at least, is Banting's Letter on Corpulence. Having lost weight and dramatically improved his health on a low carbohydrate diet. Banting wrote and self-published the book back in the Mid-Victorian era, and he distributed it for free.
Read More »The Schwarzbein Principle by Diana Schwarzbein, MD
This groundbreaking book dispels the myths perpetuated by some bestselling diet books that may help people lose weight, but will put them on the fast track to disease. Based on sound research and the success of thousands of people, The Schwarzbein Principle proves that excess weight, degenerative disease and accelerated aging can be controlled - and reversed - in a healthful way.
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