In addition to the latest knowledge of fasting, the program proposed by Dr. Mercola maximizes the benefits of extended water fasting through partial fasting. In essence, once we achieve metabolic flexibility to burning fat for fuel and are familiar with intermittent fasting, we could extend the benefits through partial fasting. That is, at the end of the intermittent fasting period we would add a single small meal followed by a 24-hour water fasting once or twice a week.
It only takes a few hours to read the book since the material is covered in 150 pages. Although relatively short, Dr. Mercola by no means forgets to delve into the details. In fact, about 40% of the book deals with the cyclical ketogenic diet and the partial fasting programs found in Chapters 7 and 8, respectively.
Let me share a review before you make any commitment. First, I hope to put together a brief summary from each chapter including key excerpts highlighted while taking notes. Then, I will share some personal thoughts and recommendations at the end.
SUMMARY
[Introduction] After a brief correlation between insulin resistance and major chronic diseases, Dr. Mercola affirms that becoming metabolically flexible—that is, being adapted to burning fat for fuel—is key for resolving most of these health challenges. Following that, he touches on the importance of cycling in and out of ketosis to achieve optimal health. At the end we learn the benefits of partial fasting—coined as KetoFast—as well as the differences between this approach and extended water fasting.
[Chapter 1] Before jumping into fasting, Dr. Mercola shares the main food-related causes that have contributed to chronic diseases. One by one, each cause is properly addressed in the book: [1] overconsumption of industrially processed foods; [2] crops grown with synthetic fertilizers; [3] food additives used to extend shelf life and enhance flavor; [4] excess iron consumption that can build up to toxic levels; [5] neglecting the importance of our microbiome health; [6] inflammation caused by a diet high in sugars; and [7] disruption of our natural circadian rhythm.
[Chapter 2] Here is a primer on the history of fasting. As Dr. Mercola says, “the history of fasting shows that humans have been fasting not just because we sometimes didn’t have a choice but because periodically going without foods provides a wide variety of other benefits, whether they are spiritual, political, religious, or therapeutic.” He walks us through religious fasting, explaining the traditions and uses. Next, some examples of how fasting was successfully used as a form of nonviolent resistance. Last, we take a look at the history of therapeutic fasting.
[Chapter 3] This chapter was my favorite: the mechanisms of fasting. Dr. Mercola says that fasting is an important health-promoting strategy because, in essence, “it’s a positive stressor to your body.” We explore in detail: [1] how it reduces insulin resistance; [2] how it triggers autophagy; [3] how it can naturally activate our stem cells; [4] how it can be used as one of the most potent ways to remove toxins from our bodies; [5] how it can help us live in alignment with our natural circadian rhythms; [6] how it trains our bodies to burn fat for weight loss; and [7] how it improves both our brain and heart functions.
[Chapter 4] Now he shares an overview of the many different ways to fast. We first learn that although water fasting is a powerful metabolic strategy, “there is indeed a dark side to water fasting that makes it far less than ideal fasting strategy for the bulk of the population.” The downside, he continues, “when the weight you lose is in the form of fat, it will typically release the toxins that have been stored in your fat into your bloodstream, exposing you to a flood of toxins.” Among the different intermittent fasting protocols, partial fasting seems to be the one that delivers the best possible mixture of fasting benefits and compliance. When partial fasting, the body mobilizes the toxins from the fat cells and, by eating a limited number of nutrient-dense foods that support detoxification, it helps the body to effectively eliminate these toxins.
[Chapter 5] Dr. Mercola addresses common side effects of fasting, as well as some absolute and relative contraindications for fasting. Insomnia, fatigue, skin irritations, mucous discharge, and visual disturbances are common side effects and are generally short-lived—they are the result of toxins being liberated from fat cells. Concerning contraindications, he affirms, “if you are underweight, malnourished, pregnant, or breastfeeding, you should not undergo any kind of fasting treatment.”
[Chapter 6] To reiterate the dark side of fasting if not done properly, Dr. Mercola delves into the details of what he had previously introduced in Chapter 4. We learn that fat-soluble toxins are widespread throughout the environment and, because they tend to be resistant to degradation, chemical toxin levels in humans have skyrocketed. It is something that, according to him, our “ancestors before the 19th century never faced when they were required to fast, because the environment simply wasn’t contaminated to the extent that it is today.” He then shifts gears toward detoxification, explaining the 4 stages, from the moment the toxin enters the cell in its fat-soluble state until the moment it leaves the cell and moves along the path to be excreted through our sweat, urine, or stool. We also learn strategies to maximize toxin elimination when partial fasting. In addition to drinking plenty of pure water and eating cruciferous vegetables, taking fiber and other binders will help sweep the toxins out. Sauna therapy is explained in great detail since it encourages passive sweating, “which is more likely to contain toxins than sweat that’s released when exercising.”
[Chapter 7] Whereas earlier Dr. Mercola focused on the many circumstances of fasting, now he explains the cyclical ketogenic diet program, walking us through the details. Following a healthy approach, this chapter is indeed a primer on the ketogenic diet. What sets this chapter apart from most of the ketogenic books, is that he addresses the potential downsides of long-term ketosis, including clear strategies to counterbalance these drawbacks by adding cyclical ketosis once metabolic flexibility has been achieved.
[Chapter 8] Once “you know all the reasons to restore your metabolic flexibility and begin engaging in regular partial fasting, all you need are the specifics on exactly how to do so.” Dr. Mercola shares a step-by-step implementation plan, beginning with strategies to minimize toxic exposure, passing through a comprehensive 5-step KetoFast protocol, and concluding with several details such as foods and supplements to support detoxification as well as a simple way to calculate our personal KetoFast calorie target and breakdown. Since the content and the program are clearly explained, there are virtually no margins for guesswork.
[Chapter 9] The last chapter is composed of 8 health-screening tests “to see quantitative evidence that your hard work is paying off.” Dr. Mercola recommends us to have these tests taken as we embark on our KetoFast plan, and again at least 3 months in. Each one of the following lab tests is explained in great detail: [1] vitamin D; [2] RBC magnesium; [3] omega-3 index; [4] fasting insulin; [5] serum ferritin; [6] high sensitivity c-reactive protein; [7] homocysteine; and [8] LDL particle number.
PERSONAL THOUGHTS
By now uncountable benefits of fasting have been demonstrated in clinical and experimental research studies. There are different protocols available depending on personal preference, health condition, and compliance. Having said that, implementing them isn’t easy at first, especially these days that we have been physically, emotionally, and socially attached to compulsive eating. It takes some discipline. That is why being adapted to burning fat for fuel is one of the premises to navigate through fasting without hunger pangs.
Although I have just finished reading the book, I have been experimenting with partial fasting during these last 2 months. Dr. Mercola discussed it openly with guests in his latest podcast episodes. Now Chapter 8 offers all the details I didn’t have access earlier.
The KetoFast program is in alignment with the one Dr. Gundry recommends in his latest book, The Longevity Paradox. To be more precise, Dr. Gundry focuses on 3 strategies to be cycled each month: fast-mimicking diet for 5 consecutive days a month, brain-wash days, and optimal calorie restriction days. If we put into practice the brain-wash day followed by the optimal calorie restriction day, one after another, then both Dr. Mercola and Dr. Gundry's programs offer virtually the same outcome. They are indeed my favorite experts concerning eating habits. I have actually enjoyed the food choices Dr. Gundry recommends for almost 2 years now, based on The Plant Paradox book. In terms of timing, I have followed Dr. Mercola’s suggestions, such as daily intermittent fasting and weekly feast-famine cycling, presented in his previous book, Fat For Fuel. With regard to extended water fasting, well it has been a dilemma for a variety of reasons. I have only recently done a 3-day water fasting for the first time, following Dr. Villoldo’s protocol. It focuses on spirituality through a vision quest in nature. Although challenging, I experienced a deep appreciation for life.
As a final digression, independently of the eating habits we choose, creating a positive and joyful relationship with the food we eat is important in the long term. In addition to food, embracing other strategies that promote our overall well-being deserve equal importance in our daily lives.
Take care,
Haical
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Reviews with images
This book shows me what I was doing wrong
I had bought Dr. Mercola's book "Fat for Fuel" when it first came out and started using it immediately. I had good results but then started gaining some of the weight back and having some of the inflammation return. So I ordered "KetoFast" and just finished reading it. Now I know what I was doing wrong and how to fix it. I was staying on the diet too long and not cycling on and off. He explains in detail exactly how to use intermittent fasting to obtain optimum health, which I am looking forward to obtaining.
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