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 »New Hope Mills Muffin & Bread Mixes
New Hope Mills Blueberry or Orange Cranberry Muffin and Bread Mix is completely sugar-free and loaded with 8 grams of protein per serving!
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