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 »Super Low-Carb Snacks: 100 Delicious Keto and Paleo Treats by Martina Slajerova & Dana Carpender
Super Low-Carb Snacks gives you 100 nutritious and delicious options for staying in the fat-burning zone—perfect for your keto, Paleo, or low-glycemic diet, or if you simply want snack options free from refined sugar and allergens such as grains, gluten, and dairy.
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