April 22, 2016

Report on a 5 Day Water Fast

BLUF - Fasting is worth trying

Lee & I recently finished up a 5 day water fast.  For those of you unfamiliar, that means 5 days (120 hours) of water only.  No food, no broth, no juice, no vitamins, just water.

Fasting calendar

As we were going through it and since we finished, we’ve been asked a bunch of questions about it.  Before I get into the answers, let me clearly state 2 things.

First, we are NOT doctors and this does NOT constitute medical advice.  If you decide to do a fast, read up on it first and make your own decisions.

Second, neither Lee nor I are fasting experts.  We heard about extended fasting (beyond “Intermittent” which usually means less than 24 hours) in a Tim Ferriss podcast with guest Dom D’Agostino.  After reading up on Peter Attia’s Eating Academy and the Paleo Leap site along with this exhaustingly long series of a vegetarian's fast, we decided to do one.

After having this post up for over 2 years and answering thousands of questions on fasting via our LiveChat, email, on social, and anywhere people could find us, we decided to compile all the questions, answers, and information we'd discovered about fasting and offer them on our store.  You should totally check them out; the combined information represents the distillation of hundreds of hours of research and years of experience.

Ok, let me go through the questions we've been asked, in order of frequency.

Why fast?

Why did we do this?
We had a few reasons.  Ketosis, autophagy & detox, tumor management, and we’re both just damnably curious about the effect of food or lack of it on our bodies.  We’ve seen what Paleo could do, and fasting seemed to fit into our understanding of the Paleo lifestyle. 

From what we understand, fasting will put you into ketosis, which means your body burns ketones for fuel.  Ketones (the things you’re burning when you’re in ketosis) are being talked about as the “fourth macronutrient”. The other three are proteins, fats, and the delicious and much maligned carbs. 

All (well, probably most) of us make ketones in our liver, although most of the time that ketone production isn’t turned up full bore because carbs are so much easier to burn.  Don’t let me get off track here, check out this interview with Barry Murray if you want to get deep.

Ketones, carbs, fats, proteins.  The macronutrients.

Being in ketosis means you burn cleaner.  When you’re eating and burning carbs, it’s like putting low quality fuel in the engine of your car; lots of unpleasant byproducts that you have to deal with. 

Race cars need clean fuel, burn ketones.

Once you start burning ketones you remove an energetic load from the body of all that post-carb cleanup.  That manifests itself (or is supposed to) in clearer thinking, less inflammation, and the ability to focus much more intensely than normal.  

Pac man autophagy, get your body to eat the bad cells.

Autophagy (or “self eating”) refers to what your cells start to do once you stop putting easily available energy in the form of food into your digestive tract.  They eat each other.  The good news is that the “good” cells go around eating up all the “bad” cells, and according to this study fasting can help freshen up and boost your nervous system.

Detox is an idea thrown around in the natural healing circles but I’m not sure how well studied, understood, or proven it is.  It seems like every diet, ingredient, or action offers some kind of “detoxing” benefit, and fasting is no exception.

The general thrust of detox in fasting is that as we start to burn fat, we release many of the toxins that get stored in fat and then pee them out.

Additionally, the digestive system, which is one of the motherlodes of the immune system, gets a break from its normal job of breaking down food and has a chance to send out little hunter-killer units throughout the body to find and kick out all the tiny little toxins that get stored to be dealt with “later”.  When you fast, “later” becomes “now.”

Fasting wrings you out and gives your digestive system a break.

The really interesting piece for us was the tumor management effect of fasting, which we’d heard about from Dom D’Agostino on Tim Ferriss' podcast.  Apparently, tumors thrive on sugars and can’t process ketones.  If you’re eating a high carb diet, the tumors can thrive on all the carb sugars.  Once you remove those in a fast and all that’s left are ketones, the tumors starve.

You probably didn’t know this because Lee is pretty private, but a few years ago we had a health scare when doctors removed a golfball sized (benign) tumor from just off her spine, deep in the chest cavity.

The docs said it was pretty normal, and that she (along with most people) probably has a bunch of tiny little tumors throughout her body that will never grow unless the right environment comes along, so part of our fast was dedicated to starving out those tumors.

What we found was that a small lump which had been getting bigger (pea sized) on the back of her neck actually shrunk noticeably during the 5 day fast.  It’s not science, so don’t go saying that fasting cures cancer, but during our N=2 experiment we noticed that in at least 1 of us, 1 small lump got a lot smaller.  Pretty good news in our house.

At the end of this list of reasons comes one of the biggest drivers for Lee and I:  What’s it like? We’re curious people, we haven’t even come close to experiencing everything out there, we know food can be incredibly powerful, and fasting seemed like a challenge, a gateway to a new state of mind, and probably beneficial.

Water.  It's enough.

What was it like?
Surprisingly, neither Lee nor I ever felt exceptionally hungry.  While we talked about food, neither of us felt that gnawing “I’m staaaarving” feeling.  I had heard that you weren’t supposed to work out during a fast because you wouldn’t have the energy, so I scheduled a very challenging workout right in the middle of the fast.  Nobody tells me what to do. :)

Boring workout details:
1 mile soft sand run with partner, sharing the portage of a 35 lb kettle bell tied to a buoy.  Enter the ocean at the end of the run with the kettle bell, move out past the surf line and walk it along the bottom in 8-10 feet of water for approx 400 yards of breath holds parallel to the beach.  Get it back through the surf zone and up on the beach, and run the mile back to the start.  Very cold, lots of breath holds, the running was pretty easy. I was dizzy at the end and needed some extra running to warm back up, but my partner didn’t notice me being weaker than normal, just that I was a little spacey on the run back.

Underwater kettlebell workout

Lee started to experience debilitating cramps in her back and legs about day 2, and like the tough woman that she is just ate the pain for the next 3 days, with 1 brief excursion on 1 night into Advil land.

I didn’t have any major problems or pain, although I slept a bit less.  That was probably more due to having a new dog in the house than from fasting; she discovered that sleeping on my legs was comfortable for her.  Not for me.  :)

Neither of us noticed exceptional clarity or focus mentally. In fact, the opposite happened; we did get a bit spacey towards the end, and both of us become more physically tired.

We both noticed the amazing amount of time that prepping, eating, and cleaning up food took in our lives, and we also noticed just how emotional of a thing food is.

Chained to food

What did we learn?
This is really a two part answer since Lee and I had such different experiences.

Nik says

I was moved by just how emotional a connection I have to food.  If I was angry, or happy, or irritated, I would immediately think of going to get a snack as a remedy or as a celebration.  Not being able to eat highlighted this habit for me in a way I’d never seen it before.

I realized just how much enjoyment food can bring.  Sharing a meal or making coffee or just prepping a quick snack are all literal expressions of our interest in growth, and removing those activities from my life made it a duller experience.

Food makes you happy.

I also discovered how much I don’t actually have to eat food, and this fast removed a limiting belief I’d had about “having” to be irritated if I didn’t eat.  I don’t have to be, it’s just an easy default choice and totally within my control.  “Hangry” is bullshit.

Lee says:

I learned that the body has the amazing ability to heal itself, and it helped me define what that means.  It made me more in touch with my body, my health, and my overall well being.

I realized how much food is a routine and a ritual and without it, I had a lot more time on my hands.  I really appreciate my tea first thing in the morning much more.

I also experienced severe back and leg pain half way through, bad enough where I couldn't sleep.  I looked it up, and that seems like it is pretty common.

What will we do differently in the future?

Nik says
I won’t worry so much about getting food in me at certain times, or worry about going even a day or so without food.  I’m making a point to enjoy even more when I eat, and to think just a little bit before automatically “eating my way out” of an emotion.

Lee says:

I would focus more on the detox end.  I had a pretty major surgery a couple years ago and I think I was getting rid of a lot of those leftover drugs from the hospital.  So I would add enemas, castor oil compresses, and I would also work-out more to move some of the toxins through. Maybe add some dry sauna, and cold plunges.  I drank a ton of water, but I think I purged a lot pretty fast and felt pretty yucky.

Yoga, sauna, cold plunges

I have a condition called schwannomatosis (I have small tumor growth on the myelin sheaths of my nerves) and had one on the back of my neck the size of a pea, and the wildest thing is that it shrunk to almost nothing. 

Would we do it again?

Nik says
I don’t have any plans to.  I think the learning points I got out of it won’t be reinforced or enhanced by repeating the experience, and I love my food rituals, the strong energy I have with my current eating schedule, and the physical, mental, and emotional results I’m getting from my experience with food.

Lee says

Yes. I would like to do it 2-3 times a year, maybe for 3 days instead. Remember, it is hard to work and run a household while water fasting. It is important to get enough rest. There is this great write-up by Paavo Airola I kept in mind during my fast:

"...your body will first decompose and burn those cells and tissues which are diseased, damaged, aging or dead. In fasting, your body feeds itself on the most impure and inferior materials, such as dead cells and morbid accumulations, tumors, abscesses, damaged tissues, fat deposits, etc.

Dr. Buchinger Sr., one of the greatest fasting authorities in the world, calls fasting - very pertinently - a "refuse disposal", a "burning of rubbish". These dead cells and inferior tissues are consumed and utilized first. The essential tissues and vital organs, the glands, the nervous system and the brain, are spared.

During fasting, while the old cells and diseased tissues are decomposed and burned, the building of new, healthy cells is stimulated and speeded up.

Amino acids, the building blocks of proteins, are not wasted, but are released from the decomposed cells and used again in the new-building of young, vital cells. As you know, your cells are made mostly of proteins and the complete set of all the essential amino acids is needed for the effective building of cells. During fasting the proteins needed for new cell building are resynthesized from the decomposed cells. Thus the body is using and re-using the same proteins and other nutrients over and over where they are needed."

Paavo quote

How did we break our fast?

At the end of the week we broke the fast with a mug of bone broth, and about five minutes later a steak and salad.  Neither of us had any problems with that.

We get this question a TON along with all kinds of "I heard on the internet that you should break the fast with [insert bone broth or tea or salad or gradual reintroduction of whatever.]" 

I've got to reiterate here that we're not fasting experts or doctors, we're cookie and beauty and excellence lovers.

We did this to try out the experience and both of us are stoked we did it.  We don't think that how you break a 5 day fast is particularly important beyond NOT slamming down 6 Double-Double Animal/Protein with Animal Fries and a Chocolate Shake from In 'N Out.  That's fairly obviously a recipe for gut disaster.  

Go easy.  Start with bone broth or tea.  Listen to your body.  After all, learning to listen to your body is one of the biggest benefits of fasting.  Enjoy breaking your fast!

Need more reading and sources?

Are you the type who wants to read exhaustively before trying something? Here's our collection of Fasting Knowledge: The Paleo Treats Fasting Knowledge Collection

What's next?

We notice that MOST of you reading this are in the middle of your fast and wondering what's next?  If you're aiming for continuing on the path of fasting, we recommend intermittent fasting. You can learn more about that in our Fasting Knowledge Collection.

We usually send out emails once or twice a week.  We aim to be useful, so you'll hear about water fasts, hard workouts, our favorite recipes, and why we (well, Nik) runs up a mountain with a mouthful of water on a regular basis.

This article made you hungry?  Here's some more reading to consume...

Nik Hawks


Nik Hawks helps run the show at Paleo Treats. Fascinated by humans in all their strange glory, Nik is harnessed in and pulling hard in pursuit of excellence with the rest of the PT Crew. Enjoy!

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Anni J
Anni J

June 01, 2020

Thanks for the article. It’s good to read your thoughts and about the experience. I have a dodgy immune system and the 5day water fast was recommended by a Dr to re-set it – BUT only with my GP and rheumatologist approval.

As I’ve been practicing Fast 800 way of eating as a basis for my everyday eating for over a year now, She thought I could adjust easily by starting out with a 1 day fast and working up gradually to 5 days. Definitely worth a go !
Carolina Romero-Thompson
Carolina Romero-Thompson

January 09, 2020

Enjoyed reading this post. Thank you for taking the time to create it. :)

Sara Schellhase
Sara Schellhase

January 09, 2020

Love this article. I appreciate your true insight on fasting . That you did it yourself truly has been an inspiration.
Thank you.


February 11, 2017

thanks for sharing! My brother and his wife (both doctors ln their 40’s) are used to fasting once a year, but they recommend to be assisted by a skilled doctor during that intense périod. In Germany or russia, fasting is well known and recommanded by health authorities. I experienced last year a 100% grapes diet for 3 days In a row and loved the feeling as well of questioning the effect of Food In my body. A direct great side effect was me quiting definitely tobacco ;)


July 14, 2016

Thank you for sharing!


April 29, 2016

Again, you both inspire me and plant seeds that usually grow into new thoughts
which then manifest into healthier behaviors and beliefs. As a juice faster, Im an
advocate and will try the water fast. Thanks so much for caring and sharing.


April 24, 2016

Yup- you nailed it ! Sue and I are trying it for one day and see how we feel- increasing days as we focus on whats truly important.
Thanks ya’ll!
Max-V Ssends

Deb vanhorn
Deb vanhorn

April 22, 2016

I have fasted regularly throughout my life. For years it was one day a week. Another time, it was for thirty days. I haven’t fasted now in years and I miss it. There is a connectivity (a sharpness) that I feel is lost.

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