Fasting is nothing more than intentionally restricting what, or when, you choose to eat. Over the years I’ve posted a good bit about fasting. If this is new to you, start with my post, Ten years and About that diet.

In my battle with depression, I’ve become convinced that inflammation is a causal factor; being over-weight is generally inflammatory and then eating inflammatory foods can tip me over into an acute episode of depression. To be clear: I’m literally saying that if my weight is up, and I eat the wrong food, the following day will be a shit-show of depression.

If you have no idea what I’m talking about—AWESOME. I’m so happy for you. (That’s not sarcasm.)

…okay, you’re still reading. Here’s something new [as in: I’ve not posted this URL on my blog before] from Pilon:

I’ve found stats saying it’s the 4th leading cause of disability worldwide and that mood disturbances including depression will lead to an epidemic of disease in the 21st century in the western world. It’s clear that depression needs to be addressed more often than it currently is in the mainstream and health and fitness media. I find depression particularly interesting because of the connection with inflammation.

~ Brad Pilon from,

Curious, it’s almost as if what I eat matters…


§11 – Intermittent Fasting

(Part 11 of 13 in series, Changes and Results)

Intermittent Fasting (IF)

With any form of IF, you can get the same physiological benefits. The key is to find a form/style of fasting that works for you and which yields the results you want. No matter what you do, it requires [what may be] a whole new level of paying attention to your body; how you feel, how much you weigh, how strong you feel, how sharp your mind seems, etc. IF is putting your food consumption and internal eating-related systems on manual. That can be great, or it can be a car crash.

I’ve come to realize that the style of fasting I do is not actually me “doing something”, but rather me living in tune with my body. The way I ate previously was automated and not healthy. I started IF as a project, and now it’s simply more normal and healthy than they way I used to eat.


“Starvation mode” is not something you have to worry about with any of these short-term fasts. You’re not going to lose muscle (especially if you continue training or weight lifting). You certainly can exercise in the fasted state; I do just that all the time. I don’t eat until Noon and I’ve done all sort of ranges of activity in the fasted state.


Cells prefer to run on glucose. Things like muscles store some glucose internally and use that initially because it’s readily available. Some cells (notably, your brain cells) don’t store glucose and must have glucose from the blood. The liver stores glucose and releases it into the blood when glucose levels drop. When the liver runs low on stored glucose, it creates glucose from fat. In that process, the liver also create ketones (small, simple, alcohol-like molecules) which get dumped into the blood and will be removed by the kidneys or expelled in the breath.

Counterintuitively, some processes in your body (e.g., your heart muscle) operate more efficiently in the fasted state. When the liver adds ketones to the blood, your brain and heart prefer ketones as an energy source, which reduces your need for glucose to be produced by the liver. (If you do the deep dive on the biochemistry, it turns out that per joule stored in glucose versus in ketones, the heart can do more work per joule when using the ketones.) There is also a pronounced mental “feeling” of thinking sharper when your brain is using ketones. “ketone hacking” is an entire universe of people, information, podcasts…

What to Eat

Fasting is all about WHEN or HOW MUCH to eat. What to eat is a whole additional discussion. Some of the things you’ll read talk about what to eat, but I recommend initially focusing only on the when and how-much of eating. Then on subsequent reading and study, you could look at what you are eating and adjust that within the framework you’re settling on.

Types of IF

Aside from the various religious fasting prescriptions, there are two main variations: “eat, stop, eat” (ESE) and “16/8”. ESE is where you fast for a 24 hour period, once or twice per week. With “16/8” you fast 16 hours every day and have an 8 hour eating window.

I prefer the 16/8 because I like the regular schedule and I can always have lunch/dinner with people. (Most people don’t even notice I’m actually fasting in the morning.)


So that’s my overly-simplified introduction to the actual introductions to IF. I suggest starting here:


Ten-years and About that “diet”…

(Part 72 of 74 in series, My Journey)

Recently a friend of mine emailed me and asked, “Hey Craig, tell me about that diet you went on a few years ago.” He was referring to what I did from ~2008 to ~2016—the photos above were taken in 2008 and 2016. Below is my response and this just happens to all coincide with the “ten year challenge” currently all over social media.

I did a few things. Each of these took a few months of trying/fiddling until they felt comfortable.

I tried to avoid refined carbs like the plague; I tried to eliminate all added sugar, all refined grain (bread, pasta, etc), and even eliminated granola which was a go-to breakfast staple (with plain yogurt). What really happened was that it forced me to become aware of the carbohydrates I was eating. I still ate pasta and bread and even sweets, but by focusing on, “I am the type of person who eats fish, meat and veggies,” I was able to shift my diet significantly. I started to make choices such as, “if I’m going to eat pasta, I’m not eating shitty pasta, I’m going to my favorite Italian restaurant so I really enjoy it.” I did not count calories. This was not fun as I [in my opinion] was addicted to the blood sugar spikes from eating a lot of carbohydrates. Shifting my dietary balance had the effect of changing my energy metabolism; it caused changes in my liver function and cellular mitochondria performance.

After many months of that, I next worked on my addiction to eating. I started intermittent fasting. (Without consulting my doctor I just jumped all in.) I did (and still do, many years later) “16/8” intermittent fasting; meaning I’m fasting 16 hours-a-day, and permit myself an 8-hour “feeding window.” (Aside: What I now call ‘normal human eating.’) The way I like to do this is to aim for consuming no food after about 7:30pm. That makes it easy to have a normal dinner, including social eating which is super important to me. Then I basically don’t eat breakfast. Around 11:30, (16 hours after 7:30 the previous day,) I have my break-fast while everyone else is calling it “lunch.” Most people never notice I’m doing this. I could talk for hours about intermittent fasting. BE CAREFUL with this; you can faint, or have low-blood sugar problems depending on how wacked your metabolism is.

It’s important to note that I did the above things separately, one after the other. My reading indicated that reducing carbohydrate intake would force my cells to up-regulate all the cellular processes for burning fat—my own pre-installed fat. So my “lower carbohydrates” work was in preparation for the intermittent fasting work. If I was planning to not eat for 16 hours, my body will have to switch to mobilizing the fat from fat cells; the liver has to be able to put glucose into my blood stream from stored-like-a-battery glycogen in the liver, and from glucose created chemically from other substrates. Those in particular were cellular processes that I was hardly using for decades, when I was always-eating and eating lots of carbohydrates.

So the big picture for me was to change my energy metabolism—to recover my [natural, normal, hey humans are awesome] ability to run on various fuels, (be that carbohydrates, protein, or fat I put in my face, or the pre-installed fat.) I did that by first reducing carbohydrates, and then starting to fast.

I’ve written some of my thoughts up on my web site, but it’s all scattered about. Let me know if you want more information on any of the above and I can give you more and point you to specific resources. If you want to learn more, start with my health or self-improvement tags.

All that said…


I can train like a machine all morning, not having eaten—in fact, if I eat I feel worse when I try to work hard. I’m considering using longer fasts (days, even up to a week) because there are long-term benefits seen in some studies; fast for a week, have improved blood markers for months. But this is definitely out in the land of, “I’m experimenting on myself.” (If you want to learn about long-term fasts, check out Peter Atia’s podcast, The Nothing Burger, it’s a long discussion of a one-week long fast he did with insane amounts of medical science.)

Finally—this is subtle but important—I did not intentionally increase my physical activity. It was not, “I’m exercising to get in shape.” My activity level spontaneously went up in response to feeling better. “I feel like running 2 miles,” is a thought I now have [sometimes] and now I can go run just for fun. It’s a virtuous cycle though; I feel better, I feel like more activity, I feel more better, I feel like more activity, …


Intermittent Fasting: A Beginner’s Guide

Beyond vanity, the reported health effects of an intelligently designed Intermittent Fasting program read like a laundry list of live longer, live better benefits including: reduced blood lipids, blood pressure, markers of inflammation, oxidative stress, and cancer. Increased cell turnover and repair, fat burning, growth hormone release, and metabolic rate. And improved appetite control, blood sugar control, cardiovascular function, and neuronal plasticity.

~ John Berardi from,

This is a terrific overview. It’s writen by a physician and is intended to get you thinking about how you eat; As opposed to trying to talk you into trying it.


How often should we eat?

(Part 12 of 14 in series, John Briffa's "A Good Look at Good Health")

When I started experimenting with intermittent fasting a year or so ago, it occurred to me that my previous beliefs about our ‘need’ to eat three times a day were just wide of the mark for me and, as it turns out, a lot of other people now. I now encourage a much more fluid approach based on the two guidelines above. One thing it’s done for me and others is to liberate us from the supposed need to eat by the clock. The benefits can be huge. In general, taking a more fluid approach seems to lead to people eating less, having more time, and being less preoccupied with food. These are usually big pluses for people.

~ John Briffa from,


Study suggests that, for optimal fat loss, the best thing to eatbefore exercise is nothing at all

(Part 11 of 14 in series, John Briffa's "A Good Look at Good Health")

The concept of endurance athletes stocking up on carbs has, I think, fuelled the notion that we should ideally have some sort of fuel inside of us prior to exercise. However, as I explain here, there is an argument for avoiding spikes in blood sugar is seeking to maximise one’s capacity to utilise fat as a fuel during exercise. I think there’s an argument for consuming little or nothing before exercise unless, perhaps, exercise is to be very prolonged.

~ John Briffa

Sometimes people don’t believe me when, around 11am in the middle of some crazy physical activity, it comes up that I haven’t yet eaten anything. I usually ask them why they think they must eat every waking hour? Why is “breakfast the most important meal of the day”? Why do you eat what you generally eat? And then I ask them to consider looking into the notions they have about nutrition…


Growth hormone may rise 300 percent with exercise

(Part 3 of 3 in series, Ned Kock's "Health Correlator")

Growth hormone stays flat for about 40 minutes, after which it goes up steeply. At around the 90-minute mark, it reaches a level that is quite high; 300 percent higher than it was prior to the exercise session. Natural elevation of circulating growth hormone through intense exercise, intermittent fasting, and restful sleep, leads to a number of health benefits. It helps burn abdominal fat, often hours after the exercise session, and helps builds muscle (in conjunction with other hormones, such as testosterone). It appears to increase insulin sensitivity in the long run.

~ Ned Kock from,


What is “intermittent fasting”?

(Part 5 of 14 in series, John Briffa's "A Good Look at Good Health")

Quelling insulin will help protect against these conditions, and will facilitate fat loss too. One way to quell insulin levels is to eat a diet largely devoid of the foods that cause surges in blood sugar such as those [of] added sugar as well as starchy ‘staples’ like bread, potatoes, rice pasta and breakfast cereals. Another way, though, to moderate insulin levels is to extend the time between eating. This, in essence, is what intermittent fasting is about.

~ John Briffa from,


Restricting your eating times

The reasons for these health benefits relate to the fact that the human body appears to be designed to thrive in a cycle of “feast and famine.” By imitating the ancestral conditions of cyclical nourishment, your body enters into a state of optimal functioning. Three major mechanisms by which fasting benefits your health include:

Increased insulin sensitivity and mitochondrial energy efficiency. […] Reduced oxidative stress. […] Increased capacity to resist stress, disease and aging.

~ Jeff Roberts from,


Muscle loss during short-term fasting

(Part 2 of 3 in series, Ned Kock's "Health Correlator")

When the body is running short on glycogen, it becomes increasingly reliant on fat as a source of energy, sparing muscle tissue. That is, it burns fat, often in the form of ketone bodies, which are byproducts of fat metabolism. This state is known as ketosis. There is evidence that ketosis is a more efficient state from a metabolic perspective (Taubes, 2007, provides a good summary), which may be why many people feel an increase in energy when they fast.

~ Ned Kock from,