The Fasting Fix by Dr Andreas Michalsen: Book Review
If you want the science without the hype, this is the most credentialed book on the list. Dr Andreas Michalsen is a professor of clinical complementary medicine at Berlin’s Charité and a practising internist, and it shows on every page.
Author: Dr Andreas Michalsen, MD, PhD, translated from the German · Publisher: Viking / Penguin Life, 2020 · Length: about 432 pages
What The Fasting Fix covers
Michalsen makes an evidence-based case for fasting and diet as medicine, drawing on the long European tradition of clinical fasting, including Buchinger-style therapeutic fasts, as well as his own research. He walks through the different modes, from everyday intermittent fasting to longer supervised fasts, and how to eat in the periods between.
The heart of the book is the evidence. It reviews studies on fasting and nutrition for weight, metabolic disease, inflammation, cardiovascular health, and longevity, then translates them into practical protocols. The distinctive angle is a clinician-scientist’s integrative view, rooted in the German and European fasting-clinic tradition rather than any single branded diet.
Who it’s best for
Readers who want a science-heavy, physician-authored overview and are happy to work through a longer, more detailed book to get it.
Key takeaways from The Fasting Fix
- Fasting is presented as one tool within a wider “food as medicine” approach.
- The European clinical fasting tradition adds context most popular books skip.
- Recommendations are tied back to studies rather than to a personal system.
- Longevity and disease-prevention claims are handled carefully, with the evidence shown.
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How it fits cycle-aware fasting
The evidence-led approach is a real strength, and the honesty about what is and is not proven is exactly the mindset we recommend. What it does not address is how a woman’s cycle should shape the timing and length of her fasts. Read it for the science, then use our page on the science of cycle-aware fasting and our overview of intermittent fasting for women to apply that evidence to female physiology specifically. The book’s honesty about risk pairs well with our guide on whether intermittent fasting is bad for you, which takes the same evidence-first view.
Where it falls short
It is long and wide-ranging, and some dietary recommendations reflect the author’s integrative and complementary-medicine viewpoint. Worth knowing, though the core fasting evidence stands on its own.
The verdict
The book to reach for when you want rigour and a doctor’s caution rather than a program to follow. Dense, but the most trustworthy science on the shelf. When you do want the program, our review of The Complete Guide to Fasting covers the most protocol-driven book on the list.
This review is part of our roundup of the best intermittent fasting books.
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