There is a free kindle promo running for my book Periodic Fasting on Amazon today. This promo is available for April 26, 2018 - all day - and depending of the timezone of the Amazon website you are using. It is available on all Amazon websites (.com, co.uk, ca, etc).
In Periodic Fasting I first adopt a historic perspective on prolonged fasting, look into some anecdotal reports from the distant past up until the beginning of the 20th century. Then, a big part of the book is devoted to the modern research on fasting (starting with the 1960s and up to the present day).
A small portion of the book is also devoted to intermittent fasting. Anyway, if you think this is a good read for you, grab a copy, and enjoy!
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Cristi Vlad Self-Experimenter and Author