April 21, 2020

Fasting: From First Hand Experience

I originally wrote this as one very long article. The preamble of which was this post:

This Is What I have Learned After Years of Self Experimentation

I broke it out because I thought it deserved it’s own separate section.

Whenever I talk about fasting, it is very often met with intense resistance.

Not the kind of standard disagreement, but often a look of fear in the eyes of whomever I have chosen to torment that day.

To learn about a new subject, you need to be receptive to new ideas. Whether or not you decide to take them on is ultimately up to you, but deciding not to hear the information at all is rarely beneficial.

You’re always going to be better informed to make the right decision if you know both sides of the equation.

So, I recommend that you have a read of that first.

First, a little bit about fasting & ketosis Link
First, a little bit about fasting & ketosis

I think it’s worth first introducing what the hell this thing is that I am going to reference a hundred times in the rest of this article: ketosis.

When fasting, after a certain amount of time, normally a couple of days, one will enter a state of ketosis. You might have heard of the ketogenic diet. It’s been around for a while, but it’s recently reached fad status as it has shown to be highly effective for some people for weight-loss, mental and physical performance (and beyond).

Also, depending on who you speak to, they might advocate eating bacon, eggs, steak and cheese ad libitum, without any guilt whatsoever as you watch your trousers fall down to your knees. Like all things nutrition, there are also those majorly opposed to this diet. It’s fairly extreme.

This is because a ketogenic diet, i.e. a diet that promotes the formation of ketones, requires you to eat around 75% of your total calories from fat (holy shit!). The rest is made up of protein and as little carbohydrates as physically possible.

Some people can get away with more than 5% of their total calories coming from carbs, but some people can’t, depending as much on your genetics as your day-to-day life (e.g. are you an athlete?). But these are the general guidelines.

One second... Yes, this is an article on fasting, but fasting and ketosis go everywhere together. Simply put:

Fasting and ketogenic diets are simply both ways of getting into ketosis.

This is how ketosis works Link
This is how ketosis works

It is a metabolic state whereby the concentration of these little guys called ketones is above a certain threshold in the blood, typically at least 0.5 mmol/L. This literally means around 3 billion ketone bodies per litre of blood.

Ketones are produced by the liver and are the last level of your metabolism when there is no free glucose left to use. These ketone bodies can then be used as energy by vital organs such as the brain.

Your body is quite the glucose addict, and it’s also pretty damn sneaky about how it gets its fix.

Besides being able to directly use the glucose that you eat in the form of sugar and carbs of all kinds, it can also covert both fat and protein to glucose.

Now, imagine that we don’t eat anything at all (fast), the body has a number of options. On your person right now, following you everywhere you go, is a composition of protein (e.g. your bones and muscles), fat (e.g. your belly) and carbohydrates (stored all over the place).

Despite starvation, your body is still looking for its fix of glucose to function so it’s going to find the stuff that’s stored all over the body, in the muscles and in your fat cells.

Once that’s used up, pretty quickly, it’s got to figure out how to get more.

It gets desperate.

Your body, which once looked like a cute, fluffy bunny in comparison, now looks like a hunk of dry-aged steak, charcoal-grilled, dripping in streams of sexy, flavoursome juices of melting fat and protein. It starts converting your existing protein and fat stores to glucose. This is called gluconeogenesis (i.e. making new glucose from stuff that wasn’t glucose);

Yet, it turns out that gluconeogenesis is the crude-oil of the body’s energy sources. While initially fruitful, it is extremely unfavourable in the long-run for your body to dive right into your skeletomuscular system for energy.

Once your body has been converting your fat to glucose long enough, it can’t help but think: “There must be a better way”. The metabolic professors put their proverbial heads together and, in a Powerpuff Girls-Esque experiment, stumble across the process of using your liver to directly convert your stored fat into energy, all while sparing your biceps.


This is done via the electric cars of the body called ketone bodies, which are way more efficient. They provide a different type of metabolism, especially to the brain which is now a glucose-addict in remission. Incredibly, the rate of ketone body production down-regulates the rate of gluconeogenesis to keep it at a sustainable level.

The body can now mine its stored fat directly for energy and it turns out that we literally have loads of the stuff.

One kilo of stored body fat contains a whopping 7,700 kCal!

That’s around 3-4 days of food!

My Fasting Journey Link
My Fasting Journey

Until I first read Tools of Titans by Tim Ferris, I never even considered the possibility of fasting. Initially, I opened the book on the section with Dom D’Agostino, for which there is an accompanying podcast (or a few now since it was so popular). Here, I also first heard about the ketogenic diet.

I was completely blown away with Tim Ferris’ claim that a mixture of fasting and ketogenic dieting completely eradicated symptoms of Lyme’s disease, which sound completely debilitating.

On top of that, they claim that ketosis helps:

  • Improve body composition & fat-Loss
  • Potent anti-cancer effects
  • Better use of oxygen (i.e. you can double your breath-hold length)
  • Maintain or increase strength
  • Increased immune function

At the time, my radar was orientated completely differently from where it is today. I was totally focussed on my mental performance but paid no attention to my physical fitness or longevity, not understanding their codependency. I also certainly wasn’t into the world of self-experimentation. I read about all the amazing benefits of fasting and nutritional ketosis, but I just didn’t have the headspace to try it yet.

Almost suddenly, a year or so after reading that book, things had changed in my life and I became more focussed on my overall wellness. I kept bumping into these ideas of ketosis and fasting. It all sounded so interesting and compelling that I started believing whatever was being written. But, without trying, it was impossible to know how it felt.

I said to myself:

“It’s time to stop reading and time to start doing,”

Savvas Nicholas in 2017

Dabbling in Keto Link
Dabbling in Keto

During the process of moving to Berlin, I did a ketogenic diet for a month. I tested my blood ketones daily and managed to reach the required levels of > 0.5 mmol/L.

I absolutely loved it; I was discovering how much I love fat. It makes everything taste so good and comes in so many wonderful forms, all imparting their unique flavours to each dish, from ghee butter to pork rind to bone-in rib-eye. And then the soft cheeses, mozzarella, burrata, peppery spinach with double cream and pecorino.

When you take a bite of steak and you can feel the juices melting on your tongue. There’s nothing better.

At this point, this was my first taste of ketosis since, probably forever. I literally cannot recall a time where I would have gone more than a half-day without a bite to eat to enter a fasted state, and definitely didn’t eat enough fat day-by-day to enter nutritional ketosis (fat was outlawed in my house thanks to the era of low-fat marketing of the 80s and 90s).

I cannot stress how much I enjoyed my first dive into self-experimentation. I definitely felt different. I noticed certain things change about myself too. I was more alert, I was less hungry (thanks to fat being really filling) and I had a great energy balance throughout the day and night (which is necessary for Berlin)!

It was also great being able to just say “no” to alcohol, which is not tolerated well on ketosis, especially beer. This fits in with my all-or-nothing nature and I didn’t have to keep making decisions. Everyone knew not to offer me and I knew the blanket answer. No thanks.

At the time, weight-loss was still the primary thing on my radar. I was nearing the end of my journey to get down to 80 kg but I had hit a plateau. Finally, after a month of keto, I had dropped a couple more kilos and I was done!

Hello, Intermittent Fasting Link
Hello, Intermittent Fasting

It’s impossible to say exactly what mechanism was the main contributor, but crucially, following a ketogenic diet also introduced me to intermittent fasting, a practice that has stuck with me ever since.

I would skip breakfast, workout fasted and, upon my return, eat a nice big ketogenic lunch, generally centred around a nice fatty bit of meat, some kind of creamy sauce, some green veggies and some cheese for dessert. The longer I trained myself, the longer I was able to extend my fasting window. I never felt hungry, even when it came time to eat and fat is really, really satisfying to the point where you just don’t want to take another bite. It might be different for you, but that’s what works for me.

Benefits of Keto Link
Benefits of Keto

One of the benefits people babble on about keto is the supposed change in alertness and mental clarity. I can absolutely attest to this. With no insulin spikes and sugar crashes, I remember being laser-focused all day.

Ketosis turns out to be quite the miracle worker for the brain. Your brain is normally functioning on glucose so when you’ve switched the engine to an entirely different fuel, it’s reasonable to expect some change in performance. In ketosis, your brain is powered by ketones.

They’re so effective on the brain that they have been shown as an effective treatment for epileptic children and other mental disorders. In the excellent Ben Greenfield podcast, when talking about ways to recover from brain trauma (e.g. concussion), he mentioned a ketogenic diet as “non-negotiable”.


But was it sustainable? Link
But was it sustainable?

Ultimately, however, my new Berlin lifestyle wasn’t entirely commensurate with a ketogenic diet. I wanted to try all the different beers, kebabs and knödel, all out of the question on keto. In the long-run, it wasn’t for me.

I like carbs too much and the social restriction was too much for that time.

I’m committed, but not that committed.

A Real Learning Experience Link
A Real Learning Experience

This first experiment in self-experimentation was priceless to me and really got me to appreciate how making drastic changes to your body, consistently, can promote real change.

With this unique learning pertaining only to me, I know how ketosis feels from first-hand experience.

If anyone tells me that all the rave about ketosis is bullshit, while I don’t need to correct them, I can politely just ask “I’d be interested to hear about the time you tried it.” Even if they had, and they said they didn’t receive any of the coveted effects, then that’s further learning for me - it doesn’t work for everyone.

Certainly, in my case, even I would argue that it didn’t work; I am not following a ketogenic diet now as I found it unsustainable.

My First Three-Day Fast Link
My First Three-Day Fast

After appetising myself with the fat-fuelled foray into ketosis, I was just getting started. My motivation came from the opportunity of self-exploration. I didn’t care if other people agreed with me or not: The journey was not about them.

Another section of Tools of Titans talked about how Tim Ferris approaches three-day fasts. Before trying a keto diet, I could never fathom abstaining from food for more than a few hours, but now I knew it was possible.

Listening to a couple of podcasts with Dom D’Agostino also convinced me that fasting from time-to-time might be good for me (contrary to popular belief).

He touts many of the benefits listed above a ketogenic diet listed above. The thing that really got to me was the anti-cancer claim. It made sense to me that, given cancer is a disease of unbound growth, giving the body a break from all anabolic activities might allow it to reset the system from time-to-time.

Despite growing research, the rates of cancer rise yearly, and I wasn’t doing anything about it. Most people don’t, they just pray that it doesn’t happen to them.

I challenged myself: “Given that I am not hit by a bus at some point in my life, and I am fit and healthy, what am I doing to protect myself long-term against the major things that might kill me?”

Ever thought how you’re going to die? Link
Ever thought how you’re going to die?

According to Peter Attia (a massive hero of mine!), if you’re over 40 and don’t smoke, you have an 80% chance of one of these killing you:

  • Heart Disease
  • Cerebrovascular Disease (e.g. strokes)
  • Cancer
  • Neurodegenerative Disease

While my risk of developing heart disease (and probably cerebrovascular) had been greatly reduced thanks to losing loads of weight and getting myself physically active with a vastly improved diet, there was nothing I was actively doing to limit my risk of cancer or any neurodegenerative diseases.

Hence, when talking about cancer, while correlated with diabetes who’s risk I have greatly reduced, the answer to my question was: “Not much”. Also, while I’m sure that sleep is probably the most important factor when referencing neurodegenerative disease risk factors, there’s plenty of literature to suggest that a healthy dose of ketones is good for the brain once in a while.

Further to that, I became totally convinced that it would have been totally normal for humans to have survived without food for a few days from time to time and that there are probably a bunch of things to learn about myself by venturing into the vast unknown of no food for a couple of days.

So I cracked on.

Basic 3-Day Fasting Protocol Link
Basic 3-Day Fasting Protocol

I followed the protocol set out by Mr Ferris. The aim is to get into ketosis as quickly as possible to eliminate muscle wastage from excess gluconeogenesis in the absence of dietary carbohydrates.

Night Before Link
Night Before
  • Eat a ketogenic meal the night before and stop early - about 6 pm. I had a steak. Surprise.
  • I was absolutely horrified about sleeping. Fasting is so rare that I couldn’t find anyone to speak to about this and I hadn’t read much literature on this specific topic. I just didn’t know what to expect. The first night’s sleep I kept dreaming of food. In fact, so vividly that I still remember the dreams today after a number of years. I wasn’t even hungry yet!
Day 1: “Hey, this ain’t so bad” Link
Day 1: “Hey, this ain’t so bad”
  • In the morning, get up whenever you feel like it and grab a big bottle of water, top-up with lemon and salt, and go for a very long walk (4 hours). I just went clothes shopping, but instead of taking the U-Bahn, I whacked on a podcast and walked really, really far.
  • Consume some fat freely throughout the day to bridge the time that you’re not yet in ketosis. A special type of fat called MCT is converted directly into ketones by the liver, which will save your muscles from wastage during this time. I was drinking black coffee with butter and coconut oil. If you froth up it all up somehow (I use an immersion blender for soup), it’s like a cappuccino on steroids!
  • In the morning, I tested my blood-ketones using a glucometer, and I had hit 0.6 mmol/L! You basically prick your finger, use a weird strip to suck it up and insert into the machine which is primarily targeted at diabetics to test their glucose and ketone levels. Glucose test strips are relatively inexpensive, but the ketone strips are pricey so I only recommend them at the very beginning of your fasting and keto journeys while you’re figuring things out. There are a few other ways to measure though!
Day 2: “Oh, this feels different” Link
Day 2: “Oh, this feels different”
  • Day two was the hardest. Especially sleeping, something that I still occasionally struggle with today in longer fasts. I’ll usually have a bad day around day 5, but then that seems to set me up to sleep well for the rest of the fast.

  • I still went to the gym daily, having recently got into barbell sports, and I even set a personal record in my deadlift by day 3. My maximal strength was certainly not diminished.

  • On day 2, hunger was bad - but nowhere near as bad as I expected. While I learnt what it really is like to be hungry, I won’t kid myself in saying that I know what it is like to be starving, even now having done a 10 day fast. I am not malnourished and I do know where my next meal is coming from, which I can guarantee will be nutritious.

    However, it did change my view completely on what I used to call hangriness. What a load of crap.

    At no point during the process did I have a diminished mood at all, so the idea that you might get grouchy after not eating for a few hours I now understand to be totally fabricated, and if you do, maybe give a fasting and you’ll see those hunger pains go away.

    Since my first fast, hangry doesn’t come on my radar anymore.

  • A note on unpleasant feelings: Initially you can just feel your stomach empty. But it completely goes away. Any bloating or constipation or whatever discomfort you suffer from chronically will magically disappear.

    It’s magical having such a light belly in contrast to one that is constantly fed a full of food and gas. It takes around 20 hours for a meal to pass from top to bottom so ask yourself: “When has this tube ever been clear?”

  • A feeling that I’d never heard anyone talk about: You get this saliva taste in your mouth. It is just the acute taste of your saliva - and nothing else. My brother, who finds it particularly unpleasant, describes the flavour “as if you’re drinking a bottle of backwash water.”

    This doesn’t seem to hit everyone though. I initially thought I was an isolated incident before writing this article but my brother spoke quite passionately about his distaste. I have, however, become quite accustomed to this and is rectified by just staying hydrated.

  • An important note on digestion and toilet function. It gets weird. Your tummy still has stuff in it but many of the markers that you use to encourage digestion and frequency are gone. You’re not eating, you’re hopefully not smelling or looking at food. You will need to go to the toilet in the early days - I have experienced all types of outcomes, from fluidity to solidarity. Expect the unexpected. I have found that after an initial adjustment period, this disappears.

Day 3: “A switch turns on” Link
Day 3: “A switch turns on”

I don’t know how to describe it, but by day 3, it’s like a switch gets turned on in your brain. As all the niggly negative things now get vastly outweighed by the positive:

  • Light stomach
  • Great, continuous energy levels
  • Laser-focused attention span and elimination of all brain fog
  • Crazy memory recall and speech fluidity
  • Improved eyesight for both awareness, distance and clarity (normally, my eyesight is shocking)
  • Massively improved efficiency - no need to shop, prep, eat food or clean up after yourself. No need to go to the toilet.
  • Amazing gum health

My Attempt At Describing the Indescribable Link
My Attempt At Describing the Indescribable

Above all, I get this strange sense of euphoria, oneness with the world and feeling of floating everywhere I go. This is totally subjective, but it’s one of the things I love about fasting.

It’s a truly spiritual experience that cleanses the body and the mind. My lifeforce, food, had controlled me but now, food still omnipresent, I am able to transcend its glutenous grip and find happiness with my being alone.

Often, life is a search for external comforts. By fasting, I am eliminating dependence on exogenous stimuli in the pursuit of transient self-satisfaction.

I honestly feel as if my mammalian brain has been activated and I am so connected with the functions of the body, unclouded by the fog of the feast and the fear of the famine.

Breaking the Fast - The Best Part Link
Breaking the Fast - The Best Part

So, while all that “oneness with everything” stuff is amazing and all, breaking any fast just has to be one of the greatest things anyone can experience, exponentially increasing in delectation with the period of abstinence.

Come day 3, I felt like I was just getting into the groove. I was not ready to stop at all! I felt like I could have gone at least two more days but, living in Berlin, I had an improv concert to attend of the amazing artist Max Easley, father of two of my dear friends. As 6 pm arrived, it was time to break the fast.

Unsure of how I would react to immediate food consumption, I decided to try a few mixed nuts they had at the event.

Oh, the flavour.

I still remember crunching into them, the aromas lifting through my nose. The taste of umami as my saliva predigested each crumb and the feeling of a solid substance going down my gullet. Mmmm. And it was just a few nuts.

Post-event, with my best friend Lyria out in Berlin, we went to eat at a Turkish restaurant nearby that I had been eyeing up for a while.

...and when I tell you that I remember every bite of the Yogurtlu Kebab I ate, I really mean that.

The taste of joy and achievement in what I had done will never be lost on me and the reward was divine.

To this day, it is one of the best meals out I have shared.

My Fasting Practice Now Link
My Fasting Practice Now

Since my 3-day deep dive, I have dug much deeper, as I write, currently in
day 7 of an 11-day fast, my second longer than 10 days.

Generally, I now fast:

  • Sunday dinner to Monday dinner every week (20h-ish)
  • Intermittently throughout the week
  • Skipping lunch for weight-loss
  • Eating lunch for muscle-gain
  • I extend that 24h start to the week once every 6-8 weeks or so (or whenever convenient or deemed necessary). For the last two years, I have embarked on a 10 day-plus fast, again, whenever it feels right.

Long-Term Effects of Fasting Link
Long-Term Effects of Fasting

While I do find that I crave and dream about certain, very specific food when fasting, over the long run, my uncontrollable cravings are greatly eliminated. The constant self-battle centred on “should I eat this, is it ok to eat that?”, are quietened massively. My hunger is massively reduced as my levels of insulin, and my body’s resistance to it have diminished.

An addiction to eating is holistic. Behaviour and habbit change will get you far, i.e. trying to eliminate the “Oh screw it, my diet’s ruined anyway” talk, but stepping into the void will teach you far more.

Sometimes, especially after being stagnant in your current physiological state for so long, you need a kick very far in the other direction to get the system rebooted. Fasting is an amazing way to reset your metabolism and insulin resistance.

Fasting is like high-intensity interval training for the metabolism and the mind. You will get a boost once you refeed, with all systems reset, all spyware expunged and all daemons excised.

Fasting Makes You Wild Link
Fasting Makes You Wild

There’s not much more primal than learning how to survive without food.

Being constantly fed is a luxury that has been forced down our throats by this age of mass-consumerism until it has made us sick.

Life has become one big feast - but it’s all relative. To enjoy the feast, you must have the famine. Think how much the Brits enjoy summer, given that winter sucks so much.

Feed-lot cows are raised in confined spaces and fed as much as possible to fatten them up for early slaughter. Are you doing that to yourself?

At WildLife, fasting is a core principle of our health, longevity and weight-loss strategy. We believe it to be beneficial to almost everyone to some degree. We believe that when you eat is just as important as what you eat.

Share Your Experience Link
Share Your Experience

Like most things, the feeling of fasting comes down to your own personal experience. For some people it works, for others, it can be a little more difficult. I’d love to hear about everyone’s fasting success stories - or even better - fails and how they were overcome.

What was the hardest part for you?

Blog by Savvas Nicholas

Join me on my journey as I explore how to become a wild Homo sapiens in a world of farm animals.