Intermittent Fasting – Finding a New Middle Ground


Last week I went back and revisited all my old posts on Intermittent Fasting. Because of the concerns I discussed in Irresponsible Health Blogging, a few posts were edited and a few were deleted. I also completely rewrote my Best Of Intermittent Fasting page. My goal was to do two things. First I did not want to be seen as giving a blanket recommendation to IF. Second, I did not want to regurgitate the science explanations that I got from other sites, some of which I now have less confidence in.

Last month when I put out the post Intermittent Fasting – Context is Likely Important, I honestly thought it was a good way to end the series. I felt it was balanced and addressed both the fans and the critics of IF. But you can’t please everyone. Some of the fans discounted my concerns and a few people on a Ray Peat forum felt even with all my caveats and experience that I’d be making a big mistake to resume even a little IF.

It got me thinking if there might be a way to reconcile the two sides.

The Benefits and Criticisms of IF

I have an idea for a different approach to fasting that might work, but before I explain my plan I want to first go over the benefits and criticisms of IF first. I see three major cited benefits for IF. They are:

  1. Learning How to Deal with Hunger – In a 2012 post I talked about how following The Zone Diet basically trained my body to be hungry almost all the time. I was always thinking about food and meal planning. For me to resume a normal 3 meal a day habit, I first had to learn to be OK with hunger. IF was that teacher. Being OK with hunger made me calmer. It allowed me to spend more time preparing meals. I learned to cook. I no longer had to reach for a protein bar to immediately kill my hunger.
  2. Fat Loss – Fat loss is about creating a caloric deficit. You can try and manage this on a day by day, meal by meal basis, but that can be costly in both time and willpower. Creating a larger deficits once or twice a week and then eating normally the rest of the week both works and can be liberating. This is the basis for the Eat Stop Eat guide by Brad Pilon. I don’t believe there is anything magical about fasting, but for me it was a simple compelling strategy that worked far better than other diets.
  3. Autophagy / Life Extension – I’m not going to go into much this topic, so I’ll direct you to the excellent post Death Will Eat Itself by J.D. Moyer. The short version is when you deprive the cell of nutrients, it begins to self clean. Many people believe this can result in many health benefits including life extension.

Now for the criticisms.

  1. Reduced Metabolism – The body is smart and if one engages in too much fasting, it can reduce metabolism. How much is too much? This is highly debatable and will vary from person to person. I cover the case against triggering autophagy in the post Intermittent Fasting – What Paleo Didn’t Teach Me. The simple explanation is that by forcing autophagy and reducing metabolism, you are decreasing cell protection and slowing down repair, because now the cell is under stress.
  2. You Don’t Need to Become a “Fat Burner” to Burn Fat – Paleo has been big on pushing the message that one needs to access stored body fat directly via low carb or ketosis in order to lose weight. This is false, as the body is always burning fat. Thankfully this myth is going away. There are still people pushing ketosis as a magical way to lose fat. Although it may be easier, it is the stressful path and can lead to a lower metabolism.

What Diana Schwarzbein Said That Resonated With Me

After the Context post, I watched the Diana Schwarzbein Survival of the Smartest lecture twice. Took notes too. She discusses how on a hormonal level we are either using or building. When we fast, we are using. We we eat we are building. And our ability to rebuild hormones is greatly reduced as we age. For women age 35 and for men age 40.

So our ability to handle fasting can be diminished as we age. If we already have poor sleep, over exercise or abuse chemicals (caffeine, nicotine) then fasting would be even worse.

What I learned from Schwarzbein was the cascade of stress hormones can cause the metabolism to tank. This lines up with the Ray Peat people and their criticisms regarding forcefully triggering autophagy. She also talked about how hormonally breaking down can feel good. It is a survival technique for the species. However, repeatedly running on stress hormones is not good and can gradually lead to chronic health problems.

Seeking an Alternative Approach to Fasting

I first learned about autophagy from Art De Vany. He mentioned in his lecture how during the fasted state the cell consumes the damaged proteins first. Diana Schwarzbein said something similar in her lecture, stating that in the absence of glucose, amino acids are broken down to make sugar. The problem is the accompanying stress hormonal response.

All this made me ask the question: Can one get the benefits of fasting without the stress hormone response? Maybe you can. If carbs and salt can suppress stress hormones and protein suppresses autophagy, what would happen if one consumed just enough sugar/salt to shutdown the stress hormones?

I did some searching and discovered the online book The Protein Cycling Diet. This book is very pro-autophagy and goes into great detail on science. To trigger autophagy it recommends following a very low protein diet. How low? 5% of less of total calories.

The problem with this diet is that capping protein at 5% is going to be tough as most foods exceed 5% protein. Even foods you wouldn’t think had much protein are often greater than 5%. White rice is 8% protein. A potato is 7%. Once you start digging through the nutritional content of food, it looks almost impossible to construct a meal with 5% or less protein.

Unless, instead of constructing a very low protein diet one greatly reduces the amount of calories.

The Ray Peat people love salted orange juice as it shuts down stress hormones. Orange juice has a protein content of 5%. Good. Raw honey, which was discussed in the post In Defense of Sugar, has only trace amounts of protein.


Photo by mbeo

The Low Stress Intermittent Fast

Here is how I envision the plan working. Once or twice a week on days when I wake up with great sleep and I have no plans to exercise, I will begin the day with a small amount of either honey or salted OJ. Then if I feel anxious or stressed during that day, consume a little more until the 22 hour fast is complete. I’ll also have a small amount of honey or salted OJ prior to every caffeinated drink to blunt the stress response. At the end of the day, I will end the low stress IF and have a normal meal.

Will this method meet my goals? I think so. First, it will teach me to deal with hunger. Not as powerfully as a zero calorie fast, but I suspect it will still be effective. Second, it will create a caloric deficit for fat loss. Third, I think but have no way of knowing that will trigger autophagy, but do it in a way that lowers stress hormones and doesn’t compromise metabolism.

One criticism might be the very act of doing this could reduce metabolism via the reduction in calories. To reduce the chance of that happening, I would not do this fast on consecutive days. When I do eat, it will a carbohydrate friendly diet.

Am I on the right path here? One question I do not know is just how many grams of sugar (OJ or honey) will be needed to address stress hormones. I’ll guess for now. If I feel cold or anxious then I’ll up the sugar/salt, otherwise I’ll lower until that sweet spot is found.

Notes For the Survival of the Smartest Lecture by Diana Schwarzbein


Thanks to a comment by Diana, I was tipped off to the July 2014 Survival of the Smartest lecture (p1, p2). It fits in with the discussion on why Intermittent Fasting can feel good in the short term but can be stressful to one’s health as one ages.

In this post I am going to save you two hours. I watched the lecture twice and took notes. Prior to Diana’s comment, I was unaware of Dr. Schwarzbein, but I have since learned that she has influenced Matt Stone, an author who I’ve referenced a few times on this site. Schwarzbein shows up in Diet Recovery 2.

She states that running on adrenaline and wearing yourself out actually feels really good – whereas rebuilding feels kinda lousy.

This sentence sets the stage for understanding the lecture. What feels good and what is good for your body might be two different things, especially in the short term. When we push dietary habits such as low calorie, low carb or fasting that accelerate the usage of stress hormones we run the risk of running into health problems. Not at first, but later.


Diet Recovery 2 by Matt Stone

Lecture Notes

Some of these sentences are taken verbatim from slides or Dr. Schwarzbein and some are my summaries.

Building or Using

The starting premise of the talk is that our metabolism is either in a building or using state.

In order to stay healthy, you must replace or restore the hormones you have used or depleted. When you use at a greater rate than you build then you are breaking down. This is accelerated aging. It feels good to break down until it doesn’t. This is the body compensating for your survival. 

Breaking down at a rate greater than one can rebuild is inviting degenerative disease. Our ability to rebuild is reduced as we age.  At one point Dr. Schwarzbein states that breaking down triggers rebuilding until about age 35 in women and 40 in men. After this point, our body greatly loses its ability to rebuild. Breaking down becomes aging.

  • Insulin is major rebuilding hormone. “insulin is your best friend”
  • Adrenaline, Noradrenaline and Cortisol are major using hormones.
  • Combined effects of these hormones determines whether building or using.
  • Can only be in building or using mode – not both.

Aging is losing the ability to rebuild and repair. Our diminished ability to process alcohol as we age is one example.

Blaming Insulin

If a body is in a highly using mode, where stress hormones are high, the body will try and compensate by making more insulin. This results in high levels of insulin in the blood stream. Then we see disease. And insulin gets blamed, when it is really adrenaline, noradrenaline and cortisol that are killing you.

Hormones Are Regulated by Your Habits

As long as your hormones system is intact, you regulate your hormones. The five elements that dictate this regulation are:

  1. Nutrition – How you eat, when you eat, how much you eat, ratios of what you eat, and your demeanor when eating.
  2. Stress – Your response to stress
  3. Sleep – How much and how deep
  4. Chemicals – What you ingest, how much you ingest (caffeine, sugar, alcohol, medications, hard drugs)
  5. Movement and exercise – And how much.

Reaching for chemicals to feel better is a sign there is something wrong with your metabolism.

Fasting, Low Carb

You can deplete your glycogen stores at night depending on how much complex carbs you had that day. Reduced carbs and fasting can make one more prone to hypoglycemia at night, which is one thing that can wake you up. Symptoms can come on slowly. It may not happen the first time, but might happen gradually over the course of years.

After glycogen is depleted. Hormones are used to make sugar from amino acids. It can take 72 hours to get into fat stores. When fat is being broken down the body is still in using mode (not rebuilding proteins).

If the body goes into stored fat that means insulin has gone down and adrenaline, noradrenaline and cortisol have gone up. The body is in the using side of the physiology. Not a place to live. This is for emergencies.

You don’t want to go into ketosis. It is all about breaking down. And breaking down can feel good (nicotine, caffeine).

Low carb dieters are inducing diabetes. They are lowering their insulin and raising their adrenaline, noradrenaline and cortisol. That drives gluconeogenesis and they start to become hyperglycemic. Eating carbs reverses the process.

When you go low-carb, cortisol goes up. Early tests will show this, but cortisol levels will drop if prolonged. Could lead to adrenal burnout.

Degenerative Diseases

All degenerative diseases of aging have:

  • higher blood sugar
  • higher blood pressure
  • excessive clotting
  • increased inflammation and oxidation

Chronic disease is your body’s way to keep you going. It does this by breaking down.

  • You do not survive with low blood sugar so the only viable disease is one with high blood sugar.
  • You do not survive with low blood pressure so the only viable disease is one with high blood pressure.
  • You do not survive without the ability to clot, so over clotting is the problem that survives.
  • You do not survive with inflammation so the inflammatory diseases “win”.

All autoimmune diseases live in the using side of metabolism.

Living Longer in a Healthy State

Dr. Schwarzbein states humans used to live to at most about 50 and if your goal is to live to 50 years old you can do whatever you want to do. However, if you want to live longer you’ve got to honor physiology and biochemistry.

Losing weight is not how you stay healthy. Being healthy is how you lose weight.

Last Words

These notes are just an overview. If you are really interested in the details, especially in regards to diabetes, watch Part 2. The lecture inspired me to seek out more information, so I’ve just started reading The Schwarzbein Principle II. As a male over 40 years old that consumes a fair amount of caffeine, Dr. Schwarzbein has got my attention.

The Schwarzbein Principle II, The “Transition”: A Regeneration Program to Prevent and Reverse Accelerated Aging by Diana Schwarzbein

Intermittent Fasting – Context Is Likely Important


Last week I was involved in two discussions on Intermittent Fasting (IF). One was extremely supportive of IF and the other highly critical. Both sides were represented by smart people and both made valid points. They each pointed to science to back up their position. Yet they completely disagreed with each other.

My view on fasting has changed a lot since 2007. I’ve gone back and forth along a spectrum of being anti-IF and pro-IF. I understand the arguments of both sides and at times I’ve been more swayed by one than the other. My personal experience has been varied.


Photo by Diana Robinson

Let me begin by saying that I am completely unqualified to comment on what happens at a cellular level. I have read experts and their opinions on the role fasting plays on cell repair (autophagy), metabolism and stress hormones. There is a lot of disagreement. I won’t step into those debates. Instead I will approach this debate as an incomplete information problem. In other words, approach this decision as an investor, which means hedging. I’ve written on this strategy in the post Approaching Nutrition From an Investor’s Mindset.

My general beliefs are:

  1. The person most likely to benefit from fasting is the person that doesn’t fast.
  2. The person least likely to benefit from fasting is the person either fasts too much, under eats, has a slow metabolism, exercises a lot, has poor sleep, or has a more stressful life. I am a believer in not stacking stressors. I cover this concept in the post Cold Exposure – Not One Size Fits All.
  3. Men are probably more likely to benefit than women. This is a common theme I’ve seen repeated across several blogs. And stocky men probably benefit more than lanky men.
  4. Fasting probably isn’t wise for children. I’m not a parent. Do your own research.
  5. The optimal amount of fasting is likely to be the least amount needed to make a positive change. This will be different for different people. And that amount will change for the individual. For some people that optimal amount is zero. For some it might be a cycle of on and off. Cycles might daily, weekly, monthly or even seasonal.

Instead of viewing fasting as good or bad, I think it makes sense to look at where the individual is at on their health journey. I want to share my story and how it changed between 2008 and today.

Stress is cited as the primary reason to not fast, but I believe it cuts both ways. There is a stress associated with never missing an eating window. Always cooking. Always grocery shopping. Always trying to make the best food decisions with time restrictions can be taxing. From the post Peat-atarians and Fear of Hormetic Stress:

Before discovering IF, I was a slave to hunger. Every 3 or so waking hours, I had to eat. IF taught me how to be patient with food. I learned how to cook, because I could now chose to eat later rather than immediately.

IF initially reduced my stress. I felt empowered. I learned I was stronger and more resilient than I had ever imagined. I cut way back on eating out and grabbing “nutritional bars” for quick calories and began discovering new foods that I could make in my own kitchen.

But then I made the mistake that many in the Paleo community did and that was take it too far. If a little is good, then more must be better? Nope.

In 2011, I did 70 consecutive days of Leangains, which is a 16 hour daily fast. During the 2nd month of the experiment I was often tired, always cold and I lost muscle. A few of his fanboys sent me emails or left comments on how it was my fault. I accepted some responsibility, but in the end I felt it was too much for me. My suspicion was confirmed when one my commenters Tauno found a old comment on the Leangains site from 2008 written by Berkhan.


This advice never made it into the 2010 Leangains Guide. Would I have done better with this strategy? Yes and I confirmed it later that summer. From my post Intermittent Fasting – Life After Leangains, I said this:

Since ending the daily 16 hour fasts, I have regained my strength and am now at the leanest point of my life. When I scaled back from daily fasts to 2-3 times per week, my metabolism kicked into gear and I started progressing again.

This was optimal for a while. Until I started losing too much weight. This was a problem that I solved and one of the tools I used was to stop fasting. Doing this increased my body temperature and increased my sleep quality. Both positive signs that I had made the right decision.


Pick Your Poison by Scott Ableman. When I am HUNGRY and away from my kitchen, I am a sucker for getting 3 tostadas from Taco Bell. That is 840 calories which has very little nutrition to show for itself. 🙁 

But I overshot my target weight and once again became a slave to hunger. With the stress of meal planning and not being able to always make good food choices, the quality of my diet got worse. Carrying around an extra 15 pounds has made me more lethargic, which hasn’t been good for my mood. To me this is my sign that it is time to start fasting again. Just a little. Maybe one 22 hour fast a week. I already know that my body can’t handle too much and I am aware of the symptoms (tired, cold, weak) if I were to push the fasting too much.

So is fasting good or bad? It was both for me. I no longer believe fasting is either magical or dangerous. Context is likely important.

Ending 30/30 Experiment With Casein (n=1)


This is quick update on the results from my experience trying the Tim Ferriss 30 in 30 experiment. The premise is to get 30 grams of protein consumed within 30 minutes of waking. Doing this is suppose to reduce appetite and trigger weight loss. Because consuming 30 grams of protein that quickly in the morning can be a challenge, Ferriss says in the 4 Hour Body that you can use whey protein shakes.

When I first did this experiment in 2013 I discovered that whey did not suppress my appetite. It stimulated it. I actually got more hungry and ended up eating more. This summer I repeated the test using casein protein, which several people have discovered blunts appetite more than whey. I came to the same conclusion.

The 4-Hour Body: An Uncommon Guide to Rapid Fat-Loss, Incredible Sex, and Becoming Superhuman
The 4-Hour Body: An Uncommon Guide to Rapid Fat-Loss, Incredible Sex, and Becoming Superhuman by Timothy Ferriss

Skipping Breakfast > Casein > Whey

Casein solved the whey problem, but it didn’t cause my appetite to drop. It was neutral. For me reducing my eating window is the more effective than 30 in 30. Since I can more easily deal with morning hunger than evening hunger, this means skipping breakfast is the best for me.

John in a comment in March pointed out what I discovered.

  1. John says

    I had the same experience with 30/30. If you look in the appendix of his book, in his own study, those who ate 2 meals a day and skipped breakfast had the most weight loss. Of course, he tries to explain this away.

I haven’t dialed in an optimal fasting window. 12-14 hours is likely the best for most days. Doing 16 hours daily was too much for me.


“You Wouldn’t Like Me When I’m Hungry!” by Dave Groehring

Intermittent Fasting – What Paleo Didn’t Teach Me


My first exposure to the idea of Intermittent Fasting came from the original Paleo essay written by Art De Vany. I read it in December 2007 and as 2008 progressed, I started tinkering with short fasts. After more than a decade of eating every few hours, it was a radical change. In late 2008, I read Eat Stop Eat by Brad Pilon and began experimenting with 1-2 fasts of 20-22 hours a week.

Although the fat loss that came from IF was a pleasant side effect, one of the main reasons I began doing IF was for the autophagy. For a full discussion on the topic, read the article Going “Green” with Autophagy as Your Evolutionary Health Care Plan by  Mike O’Donnell. I also have a description written by Art De Vany himself on the post Autophagy and Loading Trucks at UPS. In short, autophagy is the cell’s ability to recycle damaged material when deprived of nutrients.

Sounds wonderful, right? It might only be half the equation though.

In all the articles I’ve read on IF, mostly from Paleo writers, the rate of the cell is implied as being constant. By constant I mean that the actions we fasters take do not impact the rate at which the cell performs its job. That might be an inaccurate view.

Before I explain myself, I’d like to revisit an IF experiment I did in early 2011 where I did a daily 16 hour fasting (Leangains style) for 70 consecutive days. You can read the entire post if you like, but the short version is it started very well, but ended poorly. Towards the end my body was cold, I was tired and caught a cold after going through a long period of being in top health.

I don’t want to rehash the criticisms I got in comments and emails. Some of it was valid. Some wasn’t. At the time, I chalked up the problems I experienced to a lack of randomness. The body was predicting times when I would fast and would down regulate my energy via lower body temperature and just being tired. I now think that is a partial explanation.


The Bioenergetic View

In the past two years I have been reading more about body temperature and how it relates to health. Danny Roddy, Matt Stone and Andrew Kim have written about how increasing body temperature results in positive health outcomes. A highly functioning cell is working under less stress and that reducing stress is paramount to excellent health.

In November, Andrew Kim posted Diet Dogma Rears Ugly Head Again: Become a Fat Burner, Eat Your Own Crap, and Live Longer. Hopefully he won’t take down this post, as he has with so many of his previous writings. UPDATE 2017: It appears Andrew Kim took down his entire site. Here is a copy.

This is the first article I’ve read that challenges the notion that forcing autophagy is beneficial. Before we get into that, it is important to understand that in the Bioenergetic view becoming a “fat burner” is stressful. It is less stressful to the body to run on glucose, because running on fat can impair thyroid function. Lower the thyroid and your body temperature starts to drop. This is a possible explanation for my temperature issues or Richard Nikoley’s when he was strict low carb.  Note that the often repeated meme in Paleo is that to burn fat, one must deprive the body of carbs. This is not true.

Back to autophagy. From the post :

Simply put, autophagy is an adaptive response to metabolic stress that when chronically activated drives premature aging by inducing catabolic processes that outpace the renewal ability of cells.

In other words, this is the stressful path to repair. But that isn’t the only path.

Andrew Kim explains that a high resting metabolic rate accelerates cell protection and repair mechanisms by way of enhanced protein synthesis.” Reduce stress and focus on increasing the metabolic rate. The article goes on to say that autophagy is a process that occurs regardless of whether we actively try to trigger it. Forcing it and forcing it repeatedly is a stressor and that could result in a lower metabolic rate. 

Reconsidering IF

I don’t know what happens under the microscope, but what Andrew Kim has posted makes sense to me in the context of my own IF experiments. I will still engage in Intermittent Fasting from time to time, but far less than before. I still feel benefits from an occasional hormetic stress, but my metabolism comes first. Since I’ve focused on increasing my body temperature, I feel better.

2017 UPDATE: For an alternate critique of autophagy see the post The poor, misunderstood autophagy from CaloriesProper.