Fasting for 10 Days: Why I Did It and What I Learned

A 10-day water fast is intense, challenging, and miserable. It is also euphoric and transformative.

Published in

Better Humans

22 min readSep 21, 2020

A close up of a water droplet piercing the stillness of a river reflecting orange and blue back hues. — Photo by Izzy Gibson

Editor’s note: The practice of fasting for health or spiritual reasons has been around for centuries. Some of these practices, however, have similarities with behaviors associated with anorexia nervosa. If you suspect that your interest in fasting is related to compulsive behaviors, we encourage you to use the screening tool and resources from the National Eating Disorders Association to evaluate the right course of action for you.

Prior to my 10-day water fast experience, the longest I had gone without food was 72 hours — done with the goal of resetting my relationship with food during the beginning of the COVID-19 lockdown. Before that was the occasional intermittent 16:8 fast, and before that was a 30-hour fast I did as a teenager.

My experience of a 10-day water fast was intense, challenging, and miserable. It was simultaneously euphoric, transformative, introspective, and humbling. At certain times the immediacy of experience was so powerful, it muted out all extraneous channels of thought except for what was happening in the present moment. The raw humanness innate within all of us expressed through the feeling of prolonged hunger was nothing short of mind-altering and paradigm-shifting for me.

My beliefs about myself were shattered. For one, hunger is something I’ve always actively tried to avoid. If there’s a vice that I’d consider to be a crutch for me, it’d be the sensual pleasure of eating. So in a sense, tackling 10 days without eating filled me with fear.

I’ve read about individuals who have accomplished prolonged fasts, but of course, to me, it was all intellectual wonderment. “I probably won’t die if I don’t eat for two or three days — there are some people out there who have survived for weeks without food.”

So why did I do this? I just want to make it clear that this endeavor was done purely for self-experimental purposes. I also decided to use it to raise awareness for a homelessness campaign I was involved with. My fast was not an intentional act to lose weight or heal any autoimmune disorders.

I think the value of lived experience is often overlooked: Until something is experienced, appreciation for that experience can be acknowledged yet not be fully appreciated.

What’s a Water Fast?

For the entirety of 10 days, I didn’t consume anything except for water and the occasional pinch of salt under my tongue. The salt was to sate any intense hunger pangs.

There are two schools of thought when it comes to maintaining safety when fasting:

Take minerals and supplements when fasting.
Don’t take anything — just stick to water and salt, if need be.

For those in the first group, their general argument goes like this: Your body is running dangerously low on certain minerals and essential electrolytes to keep your body functioning when you’re fasting. It’s ideal to maintain those levels so you avoid muscle cramps, major fatigue, or possible diarrhea (which through my own research, seems to be a function of something you’re doing on top of the fast and not a direct cause of fasting itself).

Alternatively, for those in group two, the consensus seems to ride around the idea that consuming anything that may require your digestion to kick start is very dangerous. As you progress longer into your fast, it’s absolutely essential to keep your digestive system asleep. This means that even anything with simple starches or sugars are a no-go.

It goes without saying, but please do your research and consult a physician if you attempt to do prolonged periods of fasting. Everybody is different! What I’m about to detail is my own experience. I’m quite in tune with my body, and I’m very comfortable with what my limits are.

What Does a 10 Day Water Fast Feel Like?

Gray scale of a young girl doing a face palm, pulling on both of her cheeks — staring into the distance despondently — Photo by Henrikke Due

Hunger comes in waves. There are varying degrees of hunger — and as one might expect, hunger and time don’t have a linear relationship. You don’t just get hungrier as time passes by. In fact, on the fourth day of my fast, my feelings of hunger were overshadowed by my abundance of energy!

It was more difficult to get out of bed on some mornings than on others. Every night after the second night, it was difficult for me to fall asleep no matter how exhausted I was. There was always a gnawing hunger humming in the background with bouts of more intense hunger creeping around the corner.

Those bouts of hunger pangs weren’t debilitating except for one night when I was roughly 190 hours into my water fast — I think that night I glimpsed what starvation might feel like: The feeling of hunger wasn’t just my stomach growling and feeling weak. There was this hollowness in the pit of my stomach that seemed to draw all of my body’s energy. It truly was difficult for me to do anything except just lay there. That level of hunger was so intense — I wasn’t able to think about anything else.

Aside from hunger, my feelings of wakefulness and overall energy would also fluctuate. Interestingly enough, my mood remained quite consistent: determined with an undertone of resiliency. More on my mood later.

How Are Energy Levels During a Water Fast?

In a fasted state, I’d say my energy levels were consistent. I didn’t have a lot of energy, but it didn’t fluctuate throughout the day. As the days crept by, I only did what I had the capability to do. I didn’t want to do anything more. There were no wasted movements — not because I was being conscious of limiting the potential of wasting energy, but because I had just enough energy to perform exactly what I needed to get done.

Due to my energy levels being fairly low, I’d break up the experience of my fast into three states of being: states of productivity, states of lethargy, and states of hedonistic desire.

How much productivity did I have during my water fast?

Productivity can vary. As I mentioned earlier, on my fourth day of fasting I woke up with an abundance of energy. In fact, the energy levels lasted all day. Everybody’s anatomy differs — I’ve read different accounts where some people could group their experience by blocks of days. That is to say, between days 1-3 I felt this way, 4-6 like this, and so forth.

I didn’t have that. There was no consistent pattern to my energy levels. I wasn’t able to determine exactly how I was going to feel the next day when I woke up.

What I could count on was I’d always feel better after waking up than during the times I’d go to bed.

Overall, I was able to accomplish tasks that didn’t demand too much physical effort. Working out was mostly out of the question. However, I was able to manage everyday chores like sweeping, mopping the floor, and taking out the garbage. Slow, methodical work, such as doing my taxes (which I did in a two-hour sitting during day 8) and journaling, was also within the realm of possibility.

What I’d say is: You can accomplish some things for sure — you’ll just be doing it a little bit slower. But then again, because I didn’t have the energy to fantasize about other things and create distractions for myself, tasks I’d set my mind to would be done without wasted mental energy.

Lethargy—and I was OK with that

I found myself spending a lot more time laying around to conserve energy. Standing up was an entire ordeal by itself.

It was such a weird experience to consciously break down the act of getting into an upright position.

In the morning when I’d wake up, I’d take a few minutes or so to slowly get up. In the process of it, I’d move to the edge of my bed, slowly sit up, and spend a couple of minutes acclimating my body into a seated position. After I gathered myself, I’d stand up and have a glass of water.

Standing was difficult because if I were to stand up too fast, my vision would blur and I’d start to black out. In those instances, I’d make sure I had something to lean against. I took extra precautions by taking my time to do so — I really didn’t want to faint from overexertion (and thank goodness I didn’t).

Oh, and here’s something that was super difficult as well that I wouldn’t normally think about: Keeping my head raised while sitting was hard. The ol’ noggin is heavy, and keeping it upright is effort! It definitely made me think about some things I’ve never given a second thought about.

So the next time you see somebody who’s homeless sitting on the street and has their head hanging low, maybe consider that they’re so fatigued they’re having trouble keeping their head up.

Hunger Broke My Brain and Left It In a State of Hedonistic Desire

The amount of time watching food-related videos between days 6-8 probably amounted to a quarter of my waking hours.

I was able to accomplish a few productive things during the day: send some emails out, update people supporting my campaign for homelessness, do my taxes. Fairly basic stuff. But for the most part, if I wasn’t laying around listening to podcasts or music, I was watching food-related content on YouTube. Thank you “Binging With Babish” and Village Cooking Channel .

Oh yeah, I also made a list of all of the foods I wanted to eat when I finished my fast — it was a long list. I’m not even sure how to put this into words because it was such a transient feeling, but it was powerful. The best way I can describe it is that for an instant I craved every single food I had had in my entire life, all at once.

In all seriousness, though, I do believe the way I chose to spend my time watching food-related content has to do with some sort of primal instinct. When we see food, oftentimes it means we’re about to eat . The irony: My brain wanted to eat, but my body didn’t actually feel like eating. Refeeding syndrome is a thing, and I’ll get into that later.

Mindset for Accomplishing a 10-Day Fast

Life isn’t a race. It’s more important to move at your own pace. Fasting for 10 days really made me appreciate this mentally and physically.

When I had reached hour 72 of my 240-hour water fast, there was something incredible I had to acknowledge to myself. Every second that passes by from here on out would be new territory. In a sense, I was constantly breaking my own personal best. Just like starting something new in life, any progress is a victory.

Small victories taken by themselves don’t amount to very much, but they keep the momentum going. As with any challenge in life, it’s the momentum of the progress you make that keeps you moving closer toward your goals.

David Goggins uses a really great example in his book, “Can’t Hurt Me.” He speaks of the necessity of small sparks or small accomplishments to fuel the big ones. “A rocket ship does not fire without a small spark. Likewise, a blazing forest fire is started from kindling.”

If I were to have done a countdown, I don’t think I’d have been able to make 240 hours without any food. Can you imagine looking at the clock every time to check on your progress?

“Oh look! There are 210 hours left …. There are 197 hours, 35 minutes, and 20 seconds left …. There are 196 hours, 22 minutes, and 37 seconds left.”

That’d have driven me absolutely mad.

Chronological time is set to move at its own pace. There’s no rushing it. Acknowledging this let me accept that there was no way to rush this challenge — all I could do was let time do its thing while I did my own thing. It was important that I reframed my mindset to move toward the finish line with appreciation.

Extrapolating from this experience, I now know to trust myself if I say I’ll complete something. In the past, I had anxiety when a task I’d start wasn’t completed immediately. Perhaps it has something to do with the desire for instant gratification. All I need to do is to remind myself that things will get done at my own pace — it’s never a race.

Physiological Facts and Other Health Concerns About Fasting

Abstract blue, white, and red colours intermingling with each other — Photo by Joel Filipe

I’ll speak only about the observed health benefits I experienced during and after my fast. There’s a myriad of benefits that come with fasting. If adopted on a more mainstream level, I believe it could radically change the landscape of our health, our relationship with our bodies, and the cultural understanding of what food is.

A lot was going on in my body! What I was really looking forward to before I had started my 10-day water fast was the state my body would be in after I completed it.

Fasting and gut health

Being in a prolonged fasted state gave my cells time to repair themselves. My intestinal tract also shut down in response to being in a fasted state.

Your intestinal tract is a long series of smooth muscle that contracts in a wavelike motion. This wavelike motion is known as peristalsis, and it aids in the propulsion of the food down the tract. When there’s no stimulus, peristalsis slows down.

Two other noteworthy gut-enhancing factors that were happening: Fasting changes the environment for your gut microbiome and boosts our body’s response to cellular recycling, which is important for renewing body tissue.

We have a symbiotic relationship with the microbiota that lives in our gut. More and more studies are showing that the constitution of the bacteria that live in our gut have a correlated or direct impact on our physical and mental health. It plays a role in a list of things, including:

There’s also a lot of research happening within the realm of how varying our eating patterns can affect our gut microbiome. One study found a correlation with water fasting having the ability to challenge our gut’s microbiome to become more resilient. The same study also found that prolonged water fasting can decrease the number of bacteria known as fusobacterium, which have a causal relationship with oral and skin disease, among other sicknesses.

In a way, we really are what we eat — or don’t eat. I’ll let you make your own correlations here on how fasting can affect our body for the better.

Talking Shit

A major benefit of fasting that really had me intrigued is the capability for our body to heal our own gut. I definitely think that some form of intestinal rejuvenation occurred. After completing my fast, I noticed a characteristic change in the quality of my stool.

Prior to fasting, toilet time would leave me wiping multiple times before I was clean. After fasting, and even up to now, it’s a one wipe and done situation. I spoke to a Registered Dietitian about this and learned that the need for multiple wiping is oftentimes a sign of fat malabsorption.

For whatever reason, all of the research I did on prolonged fasts didn’t speak about this as an outcome, so I’ll break the silence: I didn’t poop at all during my 10 days of fasting ( until I did … lol ). Most probably, it’s due to the fact that peristalsis had ceased in response to the fact that no solid foods were going into my system.

I’ll also say this: Going to the toilet for the first time after a prolonged fast is arguably more satisfying than having your first taste of food. Dropping satisfaction aside, the feeling of knowing that my intestines had the opportunity to clean itself made me feel really good. I spoke with a hydrotherapist once and learned that they considered one colonic session to be equivalent to three days worth of fasting. Ten days of fasting left me pristine and clean!

Fasting and Mood

Believe it or not, I wasn’t hangry at all. Yes, irritability and hunger are well documented, but there’s a caveat to it. Often, negative emotions are associated with hunger, in part due to the unpleasantness hunger brings. But it’s also the environment that you’re surrounded in that frames your mind to interpret certain stimuli in a negative way. In psychology, this is known as priming.

Fasting has all of the same components that would provoke very similar emotions to being “hangry,” but it didn’t. I’d attribute that to my state of mind as well as my mindset.

During the first two days, as my body was acclimating toward a fasted state, there were minor swings in my mood: from minor irritability because of discomfort (I was cold, hungry, and had a minor headache) to partial despondency — as documented from what I noted at the time:

“It’s interesting how a full stomach can affect my level of confidence. Thoughts that lead me to question my worthiness that are usually filtered out have been flooding my mind since I started this fast. Is there a correlation between my self-confidence and my satiety level?” — Author’s thoughts, day 1

But for the remainder of my fasting experience, I just didn’t have the energy to feel anything else that wasn’t beneficial to my conservation of energy.

What I mean by that is I had no interest in anything that took an excess of mental energy to sustain.

More importantly, it didn’t even feel like a choice. It was as if the primal parts of my brain had been sparked up, and anything that didn’t contribute to my survival was abandoned.

Don’t Kill My Vibe — Fasting and Its Affect on Emotional State

It’s well known that psychosomatic manifestations of mental illnesses such as depression can lead to states of fatigue. I have this theory (definitely unoriginal and heavily influenced by the work of Dr. David R. Hawkins) that our states of emotions are intrinsically tied to our energy levels.

In Hawkins’ book, he writes about something we’ve all intuitively experienced. Negative emotions are in the state of what he classifies as a lower frequency — for the most part, being around negativity leaves us feeling drained.

Also, depressive states — as well as states of anxiety and uncertainty — have a quality of intensity to them that something like contentedness or serenity doesn’t.

A chart: the X axis represents negative to positive emotions. Y axis represents low to high intensity emotions. — Dr. Emma Seppälä speaks about the capacity for high-intensity emotions to have the power to drain us

This is why I’m guessing that there was absolutely no room for my headspace to harbor any complex thoughts of negativity. It’s an absolute energy drain. As stated earlier, for the most part, my mood was consistently determined with an undertone of resiliency. On top of that, most of my day felt quite serene.

I’m curious to know how regularly fasting can alter the neural networks of our brain for the better. Research done on fasting and mood disorders have shown a correlation to boosts in vigilance and feelings of well-being.

Fasting and Meditation

Trying to distill the quality of meditation in a fasted state is a little abstract. Every individual’s meditation practice is personal to themselves. Time spent exploring meditative states or engaging in activities that induce flow states also affect your experience with meditation.

It was difficult for me to do seated meditation unless my back was propped up against a wall — staying upright took a lot of effort as the days progressed. There was one afternoon I was soaking up the sun’s rays while doing some deep breathing, and it felt fantastic!

As I said earlier, most of what I could do was lay down, so I spent most of my time doing diaphragmatic breathing. It felt as if my mind had an edge to get into meditative states. My emotions and my mood were very stable, so I took complete advantage of that.

The biggest takeaway I can share from being in a fasted state and practicing breath-guided meditation is this: The mind is a lot less busy (read: fasting and mood). As a result of a less fettered mind, my meditations would definitely go deeper than usual.

Feeling Cold

I was cold all of the time. When the body expends energy, heat is produced. The expenditure of energy also includes the breakdown of the most basic molecule humans rely on: glucose.

To split up glucose (known as glycolysis) to be usable fuel for our body, the sugar molecule undergoes something known as cellular respiration. During the process of cellular respiration, heat energy is released. In addition to the heat energy released during cellular respiration, there’s also heat energy released when we expend energy through the process of digestion.

According to Precision Nutrition, the digestion process itself can, on average, take up to 10% of our daily energy expenditure. This number rises depending on what it is we’re digesting.

All that said, in a fasted state, minimal energy is being utilized, and nothing is being digested. Hence why I was cold all of the time.

My extremities, in particular, were the coldest, and my core temperature definitely felt like it dipped a little below average. Feeling cold is never a comfortable state to endure, but there have been several studies linking lowered body temperatures due to calorie restriction as an outcome for a longer lifespan.

Other Anomalies: What Ketosis Tastes Like, White Coating On the Tongue, Detox, and Weight Loss

Ketosis: From day 4 and onward, there was a constant taste of ketones in my mouth. It wasn’t pleasant. It was a constant taste of fermented sweetness that was slightly metallic. I eventually had to get a couple of bottles of carbonated water to distract myself from the taste.

Detox: In some personal fasting journals I read online, some have spoken about a white coating on their tongue. I can attest that this was certainly the case. Some sources I found on YouTube mentioned the white coating on the tongue is a sign of your GI tract being shut down.

Alternatively, the white coating is also an agreed-upon phenomenon in the Ayurvedic/holistic medicine world as a sign that detoxification is happening.

Speaking of which, another sign that detoxification is happening is said to be headaches during the first 24-72 hours of your fast. I had minor headaches — but they didn’t last too long.

Weight: I lost a lot of weight! On average, I lost about a pound a day. In totality, I lost close to 14 pounds or 7 kilos over a span of 240 hours.

A weight tracking chart showing a negative slope between day 1 and day 10. Average weight lost per day was about 1 pound. — Weight tracker courtesy of LIFE Apps

There was a very interesting correlation I noticed as I was taking my weight and tracking my energy levels. Between day 5-6 and day 7-8, I lost close to 1.5 pounds. Those two days were the roughest days I experienced during my fast. My energy levels were so low — it made functioning tough.

Skin: My skin also cleared up a lot during my fast. General acne and blackheads had disappeared for the entirety of my fast and for the following two weeks. It wasn’t until I started eating fried foods and some sugary foods that acne started coming back.

Fasting and Refeeding Syndrome

During WWII, there were documented cases of life-threatening reactions to the reintroduction of food to survivors who were suffering from prolonged periods of starvation.

It was quite the head-scratcher for those working in the infirmary. Surely, if you’re suffering from malnutrition, the cure is to eat as much as you can!

Quite the contrary. Overindulgence of food after a prolonged state of not eating can actually cause death. That was what was happening to the survivors: Under a malnourished state, most survivors ate too much too soon. What happened afterward involved a series of different symptoms, including:

Fatigue
Weakness
Confusion
Seizures
Edema
Irregular heartbeat
Cardiac arrest
Coma
High blood pressure

This was later coined as refeeding syndrome.

I had done some research into what one should be aware of when doing prolonged fasts. It became very obvious that the thing I should look out for was the dangers of eating again postfast. At the time it didn’t make very much sense to me — I had reasoned it as a shock to the system because the intestinal tract had shut down for a long period of time. I wasn’t entirely wrong, but it’s a lot more nuanced than that.

So what’s refeeding syndrome?

To understand this, we need to acknowledge our body’s use of phosphorus. Aside from being building blocks for our bones and teeth, phosphorus plays a big role in intracellular function. That’s the functioning of a cell within itself (as opposed to between other cells).

Our cells function through the usage of adenosine triphosphate (ATP). You can think of ATP as the currency of cells; in order for a cell to power itself, it utilizes sugars that we consume through food and transforms said sugar into ATP through a reaction known as the citric acid cycle or Krebs cycle (hurrah grade 11 biology!).

As you might have noticed, the P in ATP stands for phosphate, which is a form of phosphorus.

In a fasted state, our body has shifted over from the usage of carbohydrates for energy (glycolysis) and has started breaking down fats and proteins in order to produce energy. This is known as the infamous ketosis and also utilizes lots of electrolytes, including phosphate.

A sudden reintroduction of carbohydrates causes a huge spike in insulin. This promotes the cellular uptake of phosphate. There’s also the sudden shift from ketosis back to the process of glycolysis. This also impacts any free-floating (and already low levels) of phosphate in our blood to be taken up by cells.

The chain reaction here: Phosphates needed to provide for cellular function unrelated to digestion — for example, the heart or major muscle groups — won’t have enough to perform their function, thus leading to irregular heartbeats, weakness in muscles, or cardiac arrest.

All that said, eating too much too soon will shock the system by messing up the electrolyte balance in our blood and cells. Sometimes the damage can be irreversible.

How did I reintroduce food after my fast?

Assorted fruits and vegetables on a green surface — Photo by Vitalii Pavlyshynets

The first 10-16 hours of my refeed stage was all liquid-based foodstuffs.

I kick-started the refeed cycle with cold-pressed juice. The taste was amazing — imagine having sugar for the first time after 10 days of not eating and 6.5 days of keto-breath. It engendered the sincerest form of appreciation.

The effects of energy from sugars were quickly noticeable. Within 20 minutes of eating, my body started to warm up again, and I could move from a seated to a standing position much faster.

On the first night of my refeed cycle, I had a bowl of blended spinach, kale, and chickpea soup with a bone-broth base.

I followed up the second day of my refeed cycle with more soup and had my first solid food: some nuts (almonds, cashews, Brazil nuts, and walnuts).

For the most part, I’d describe the first 50-60 hours after my fast as cautious eating. I ate foods that were easy to digest: boiled eggs, sardines, fruits, nuts, steamed vegetables, steamed chicken breast, soup, and fruit smoothies.

My appetite wasn’t huge, so I wasn’t eating very large meals either. I also stayed away from dairy and alcohol during this time (I’m moderately lactose intolerant).

I wasn’t eating full meals until the third day — and even then, it’d be one full meal a day plus light snacking throughout.

How Did I Feel After My 10-Day Fast?

I’d have to say that I seemingly did everything correctly. During my fast, I didn’t experience any health issues that were disconcerting in any way. There weren’t any health ramifications after my fast either. In fact, my overall health and energy levels improved.

My mind was sharper. My mood was better. Energy levels were stable and never crashed. In fact, my energy levels were so high for the first two weeks after I started eating again. I was so productive — it felt incredible!

I felt more motivated to do things in life. I’d definitely attribute that to the quality of challenge that a 10-day water fast posed. Accomplishing the challenge left me feeling like a winner. I glimpsed having the mental space to say I can do anything I put my mind to — and to believe it!

Overall, I just felt like a better human. My fast felt like a hard reset for my body, so it gave me an incentive to treat it well. I did that for about a month and slowly allowed myself to get back into some old habits.

Finals Thoughts About Fasting

I’m interested in experimenting with medium-length fasts in the future. Although I’d consider doing a 10-day fast again in the future — it’d be a lot more practical to try a shorter period, such as five days. The health benefits that I’m interested in exploring seem to maximize around the five-day benchmark:

Fat burning
Cellular regeneration
Promotion of growth hormone secretion (up to 5x)
Improving insulin sensitivity
Improving immune functioning

Although I’m speaking anecdotally, it seems to me that any more than five days, and it’s less about the health benefits from fasting and more so about the mental challenge of it all.

I do recognize that everybody’s physiology and anatomy is different, and others may benefit from longer or shorter fasts. Due to some incredibly challenging autoimmune disorders, some people do hard resets for their body by fasting for lengthy periods of time.

There’s also an established holistic practice based in Germany that centers their therapeutic approach to total body wellness around fasting.

My experience has completely altered my understanding of the human body. We have mechanisms that have been hardwired into our bodies from thousands of years of evolution that we’re not fully appreciating in modern society. The verdict is in: Fasting is a powerful tool that affects our body, mind, and spirit. It transformed my mindset and showed me that we’re capable of so much more than we think we are.

Summary of my experience

Fasting, like anything difficult, allowed me to appreciate life way more.
You don’t get hungrier as the days go by. Hunger comes in waves.
I had a mental boost from the feeling of hitting reset for my gut.
Energy levels were stable: not high, not low, generally moderate to low
Productivity levels were good for nonphysical tasks.
I didn’t have any energy to have extraneous thoughts; my emotions were stable; my mood was stable.
There are a lot of health benefits from fasting, mentally and physically.
When eating again, you should be careful of refeeding syndrome.
I didn’t eat solid food until the second day and didn’t start having full meals until the third day.
I was cold all of the time.
I was light-headed often — especially if I stood up too fast.
I only had a headache during the first 24 hours.
I lost close to 14 pounds.
Your tongue gets a permanent white coating after 3-4 days of fasting.
Keto breath isn’t pleasant, and the taste of it is something akin to minerally fermented sweetness.
Was it difficult? Sure. Would I do it again? Yes, I’d do it again — maybe in a less extreme way; five days would suffice.