The Complete Guide to Fasting is finally available!


I’m happy to finally be able to say that my book The Complete Guide to Fasting is now available in Canada and the United States. The Kindle version should be available very soon, and the audiobook will be released in several months.

I co-authored this book with Jimmy Moore, who has written several international best-sellers already – Cholesterol Clarity, Keto Clarity and The Ketogenic Cookbook. I first met Jimmy in Cape Town, South Africa during the Low Carb Summit in 2015. Jimmy was familiar with fasting, having tried it a few times himself and also writing about it very briefly in Keto Clarity.

Most of the speakers there follow the Low Carb, High Fat or Ketogenic approach, but I tend to use incorporate intermittent fasting quite extensively in my Intensive Dietary Management (IDM) program. There are many synergies between the two approaches. Both have the goal of lowering insulin, which I believe as the key drive of obesity. However, intermittent fasting tends to be more powerful than LCHF diets since it restricts everything. Also, people who follow ketogenic diets find that fasting is quite a natural extension of their diet. Since their body is already fat-adapted, there is a far easier transition to fasting and most people find that it is very easy.

Further, fasting brought many advantages not found in traditional diets. It was very easy to understand. It had a long history – the oldest dietary intervention. It was free (actually saves money). It doesn’t take time (it actually saves time – cooking, cleaning, shopping). It was powerful. It was simple (just don’t eat).

We’ve been using intermittent fasting in the IDM program for over 5 years and have supervised over 1000 patients with this approach with tremendous success. It’s not an approach that everybody likes, but it represents an important option for those willing to give it a try. There are virtually no other clinics in the world that offer this detailed knowledge of fasting. I suspect that we have more experience with fasting than anybody else in the world. By a factor of 4 or 5.

How we got started on the book

After the conference, I started talking with Jimmy, who became interested in fasting again and thought he might give it a more serious try. I had just finished writing The Obesity Code. While it did mention fasting in the last chapter, the focus of that book was understanding the underlying causes of obesity. There were still many things people kept asking.

toc-v2How to fast. Common problems. Who should not fast. Different types of fasting. Different lengths of fast. Will I lose muscle. Will I go into starvation mode. There were endless questions not answered by my first book. These were issues that Megan Ramos, my IDM program director and I deal with daily.

One day, Jimmy asked me what was the best book to read about intermittent and extended fasting. I’ve read everything available. I’ve read all the studies. I’ve read everything online. This is not actually very difficult because there is really nothing out there. So, that’s what I told him. There were basically no good books on intermittent fasting. Some books dealt with fasting from a spiritual perspective.

But there was nothing that a regular person could go to their bookstore and buy a book that discussed fasting as a therapeutic option in a serious manner. So we decided that we needed to write it.

We scoured the globe for the other leading experts, including Mark Sisson, Robb Wolf, Abel James, Megan Ramos, Amy Berger, and Dr. Thomas Seyfried, who all agreed to lend their expertise to this important venture. Together, we’ve put together what I believe to be the definitive guide to fasting, the ‘Bible’ of fasting that will be able to guide many people through this journey.

Intermittent fasting resources on Diet Doctor

I believe this book will be a tremendous resource but there are also many great fasting resources available online, as well. By far the most useful is the page ‘Intermittent Fasting for Beginners‘ on which is completely free. On my blog,, I have written an extensive series of posts on fasting starting with part 1, a history, and lasting 26 parts so far. All that information is completely for free, if you can put up with my occasional ‘salty’ language and propensity to say exactly what I think.

For subscribers of, however, there is a 9 part detailed fasting series of videos that will guide you step-by-step through fasting. I travelled to Sweden to film this series with Andreas and I’m very proud of it. The video series presents all the information clearly, concisely, and with beautiful graphics and video production. It’s some of the best work I’ve done. Andreas and his team helped refine the video and we did take after take. It was exhausting, but the finished product is quite remarkable and not available anywhere else in the world. For a mere $9/month, I cannot think of anything that will improve your health more. There’s even a free one month trial available.

Also on the subscriber side of, I answer reader questions. I cannot legally answer personal medical or dietary questions, but general questions that are not addressed elsewhere, I am quite happy to answer them within a few days (usually).

If you think you need a personal dietary counsellor to help you achieve your goal, I’ve also set up a program for that, too. You can join at to connect with one of our counsellors who have guided hundreds of patients through LCHF diets and fasting. There is a fee for this service, but we’ve kept it as low as possible ($500 Canadian per year). We provide this program online, so it can be delivered anywhere in the world. We have literally more experience with helping people fasting than anybody else in the world.

Together, we are dedicated to healing the world, one person at a time. We’ve put enormous resources online, mostly for free, along with books, videos, blogs, and even personal coaching. There is nothing to stop you from taking back control of your health from the drug companies and the charlatans who have ruined it. It’s a revolution – the nutrition revolution!

Jason Fung

Order the book

Order The Complete Guide to Fasting on Amazon


Intermittent Fasting for Beginners

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  1. michael
    Your link to order the book is broken
    Reply: #3
  2. Heather
    Sadly not available in the UK yet; I have a possible dispatch date from between November 10th and December 3rd... :(
  3. Dr. Andreas Eenfeldt, MD Team Diet Doctor
    Fixed, thanks!
  4. Maura
    I appreciate the DietDoctor videos, which is how I became interested in IF.
    I pre-ordered this book via iTunes, and was happy that it automatically downloaded (US) on 18 October early a.m.

    However, when I started to read it on my iPad in the evening, I couldn't bump up the font size as I normally can with the tablet. (The tablet is now on iOS 10.) Then, I tried to read it on my phone, but again could not find a way to bump up the font size and the only way to enlarge the text is to continually pinch the screen -- which is not a good reading experience! (The iPhone is also at iOS 10.)

    I pulled it up on the desktop this morning, and again -- the feature that lets me enlarge the font does not seem to be working even on the desktop. (running OS 10.11.6)

    Is anyone else having trouble enlarging the font size on this book?
    I've never, ever encountered this problem on any eBook, and I have TONS of them.

    Reply: #5
  5. Matt
    I'm having the same problem. It's really annoying. Did you find a solution?
  6. Corinne
    I just bought the book. I did the original Atkins and loss 40 pounds, but stopped because of the bad reviews from the medical field. Did not want to eat breakfast. But it was the most important meal out the day. I went on the recommended low fat diet and gained a lot of weight and gained more weight. I wish this book came out 30 years ago.
  7. Marcia
    I am on this journey and it has changed my life! I have my adult children who are morbidly obese on it and the weight loss is incredible! More importantly, we are all focused on changes that last a lifetime. I believe in this approach above all other methods. So much so that I am studying to be a certified fasting coach and a certified nutrition coach. I have lost 80 lbs. and have 60 lbs. to go. My boyfriend is at his goal weight. My oldest son lost over 40 lbs. in 6 weeks. My youngest son has lost 43 lbs. in 3 weeks. My oldest son's girlfriend is only 29 lbs. away from her goal weight. I feel great because I know that this is forever. I can easily maintain my weight using fasting once I reach my goal weight. (and it all started at the beginning of time!) Shame on the medical community for misleading people when it comes to getting healthy and staying healthy! All they want to do is sell FAD DIETS that DON'T WORK. Fasting is free and with a healthy lifestyle can be a permanent way of life if you want to stay healthy.

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