First, this isn’t really a health or body-hacking blog. It’s an account of escaping corporate cubicles, and instead enjoying a life of backpacking travel. I happily share my travel adventure stories from around the world.
I have no idea why Google is convinced I know something about kidney pain during water fasting other than I experienced it once. I’m simply a lowly travel writer who tried his hand at a five-day water fast, had kidney pain, and ended up quitting (because I didn’t do it right).
There. You’ve been warned. Now, on to my water fasting experience.
I could feel every dimple and imperfection on the blueberry as I rolled it around on my tongue.
It was like eating a blueberry for the first time. I could even sense its temperature with my mouth. When I finally got bold enough to chew it, the flavor was surprising. So was the sound when I swallowed and it hit my empty stomach, which then convulsed in surprise and annoyance that we were starting with fruit rather than saturated fat or some of the carbs I was craving.
Going just these 2.5 days (around 60 hours) with no food has given me a new appreciation for both eating and the people scattered around the globe who can’t eat when they want. Food insecurity is real for far too many people.
I am a failure. After nearly 60 hours of starvation, just barely halfway through my planned five-day water fast, I had to stop due to kidney pain. When I awoke this morning, my right kidney was swollen, and it felt like someone had stuck me with a dagger. I could barely drag around the house, and to make matters worse, I had a photo shoot to do for work. Nothing like trying to get people to smile for photos when you’re in so much pain you can’t straighten up all the way.
I know, I know. I can hear the “I told you so” resonating all over the internet.
As soon as I posted the start of my five-day starvation period, I mean water fast, I received a hail of criticism on the web. Big surprise there given how mean the internet has become. I blame Reddit. Try sending me cat memes instead.
Facebook, Twitter, email — you name the network — the nastygrams blasted like a winter storm into my various inboxes. Yes, I know deliberate starvation is one of my more half-baked adventures, but isn’t there a thin line between genius and madness? Completing a five-day water fast has been on my life bucket list for years, so I wanted to try.
Don’t worry. I do appreciate the concern, but I’ve got a date to climb a jungle-tangled Sumatran volcano in the near future. I definitely won’t jeopardize that with voluntary kidney shutdown. Kidneys are useful, both in the wild and while still at home.
2017 Update: I climbed an even bigger Sumatran volcano this year!
While consuming so much water (two full gallons a day) to fill my stomach, I assumed that I would be flushing my kidneys — a good thing, right?
Wrong. A quick check with DuckDuckGo (try it) confirmed that many people suffer the same back-and-kidney pain while water fasting. Apparently, drinking that volume of water has the opposite effect on your kidneys. Organs aren’t happy about having to work overtime to process so much new fluid unexpectedly. I learned that the hard way.
All that waste rides a rushing river down to your kidneys and accumulates faster than they can clear it. Doh!
Fun Observations From My Water Fasting Experience
The First 24 Hours of Water Fasting:
- The fast was mainly psychological. My stomach rumbled, but there were no other negatives other than my lack of concentration on anything not edible.
- I consumed two gallons of drinking water. I did get a slight head rush from the sudden drop in sodium since I was not getting any salt in food. Plummeting sodium levels can actually be dangerous.
- I couldn’t sleep a wink — partially because of hunger pain and partially because I strangely had a lot of energy. Metabolism change?
The Next 48 Hours:
- I felt dizzy because of low blood sugar and drank a glass of juice. At this point, it was no longer technically a water fast. The juice may as well have been a tall glass of absinthe — the sugar made my head spin and warmed me up immediately. The sensation was strange.
- I no longer felt hungry unless I saw food or walked by the kitchen.
- Energy levels dropped significantly, and I had all the physical motivation of Jabba the Hutt.
- I drank another two gallons of water, but my back and kidney were already starting to hurt — I knew the gig was going to be up soon.
Starting weight: 178 pounds; ending weight: 175 pounds. A loss of only 3 pounds. (side not: I am 6’1″ / 185 centimeters, so pretty “average” weight for my height).
Per VeryWell.com: 1 pound of fat = 3,500 calories. Their diet calculator says I need 2,577 calories a day to maintain my current weight — wow! Water fasting weight loss is possible but tricky. My goal was never weight loss, more so detoxification and just to see what happens.
Who knows. I’ve had a few close calls while on adventures. What if I had to go without food for a few days until rescued?
Trying to show some restraint, I ate only a bowl of soup to start back into real life. My stomach is pretty messed up.
No more water fasting or kidney pain for a while, but I haven’t given up on the idea completely. I do regularly observe simple daily intermittent fasting — it’s much easier and work well for me. I will reattempt another three-day water fast again sometime in the future but this time a little better prepared.
This crazy guy in Pai, Thailand (imagine that, in one of my favorite places) managed to go for 40 days without food! Given how much I enjoy the healthy food choices in Pai, that doesn’t sound very easy to do.
Fortunately, I encounter plenty of delicious — and sometimes terrifying — food while vagabonding.
Greg is a full-time vagabonding writer and adventurer who escaped the corporate world. Now he helps others begin a life of travel.
Wow, 3 out of 5 days is no small accomplishment! Glad to hear you came through you fast safe and sound.
Whew, I also began a five-day fast and experienced those awful kidney aches during the process. I inadvisably stuck with it for the full five days, and my kidneys still ache after a week of “real food”. Worst of all, I can’t really be forgiven for my poor choice–I have a history of kidney disease, and simply didn’t do the necessary research to learn that this might be a bad idea. Even worse, I marched on with the fast AFTER my poor kidneys began rebelling. My doctor says it should be okay, but will take time to heal. I suppose the moral of the story is: research well before you dive into a water fast, and listen to your body during the process! Don’t be a hero, as they say (in my case, an idiot).
I finished a 7 day water fast a few months back. Well done for making it that far. You actually got past the really hard part. And those kidney pains suck, but from what I’ve heard, don’t cause any damage. Mine only really were present in the mornings and evenings, when I was moving less. They went away by day 5.
I have been fasting at least once a year for 40 years. I find that the fast has little value unless you go at least two weeks. By the way, the only fast is the so called water fast. Anything else is a diet. There are a lot of aches and pains the first few days depending on your level of bad habits and toxicity. After that, hunger disappears and the fast is quite comfortable. You should have gutted it out. You would have enjoyed it
You definitely broke the fast when you drank juice. You didn’t complete 5 days at all. Please look up water fasting. You will see that you must consume ONLY water and if you drink anything else or eat a morsel of food your fast is broken because your body comes out of ketosis.
Listen to a podcast by Tim Ferriss interviewing Dr Dom DAgostino. It’s an eye opening amount of information, explains the kidney pain and the amazing benefits of ketosis. Also, you can eat and stay in ketosis, but no sugar. Congratulations and good luck. Keep fasting.
To the person who said “even a morsel of food” knocks you out of ketosis… could you elaborate? How is that possible if high fat low carb keeps you in ketosis? That’s definitely more than a “morsel” of food.
Technically ketosis doesn’t end when you eat food, but rather when you eat too many net carbs in a day. There are ketogenic diets that allow eggs, vegetables’ almost any kind of meat, butter, cheese, and more. I am on day 4 of my five day fast and i am excited to start my ketogenic diet to stay in ketosis.
Go careful with the water, electrolyte balance is important. Your body actually produces some metabolic water from fat breakdown while you fast, so forcing water down just to have something in your stomach is not a great plan. Makes you hungrier if you keep stretching your stomach too! Anything can be toxic in the wrong quantities, homeostasis is the goal to let your body rest, heal and regenerate. Peace + Healing.
I recently completed a 5 day water fast only. I did however on day 3 add a tiny amount of lemon juice and a pinch of Himalayan sea salt.
Since completing my fast I am a whole new person. I now sleep well after being an insomniac. I no longer crave all the bad foods that I was otherwise unable to deny. My mental and physical energy levels are the best that I believe they have ever been. Honestly, I have never felt so great in all of my life! I am 42 years old but feel as thought I am much younger now. Everything about my body has changed in so many positive ways. My whole outlook on life has changed! I feel so positive!
I’m now almost 3 weeks since starting back on food and have begun to try and only eat 1 meal a day. It seems to work well for me. I’m stronger then I’ve ever been. More confident then I’ve ever been. And more happy then ever. I’m eat a very clean diet and I’m staying away from most of the foods I use to indulge in.
I highly recommend giving it a try so long as you are healthy enough to do so safely. And have the proper support behind you. It just may change your life!
Jake
Great to hear about your positive experience, Jake! Way to go! I may email you for some more details…it may be the year for me to give fasting another go.
I see where you went wrong.
It is best to be in ketosis before starting the fast so that you are fat adapted first. [low carb diet, no fruit juice or sugar and low starches, moderate protein, high fat] Then when you are fasting the body is burning body fat for fuel. While fasting you NEED to add pink sea salt to your water, to keep your electrolytes up. Your body cannot function without salt. That fruit juice would have spiked your insulin and thrown you right out of ketosis and upped your blood glucose. And maybe two gallons was a bit much for water intake, maybe drink 8 to 10 cups of water. Epsom salt baths could add magnesium into your system as well. I have done two 5 day water fasts and this last time I did have some lower back /kidney pain.
I kill kidney pains when I fast with a coffee enema.
I also now find that dry fasting is easier. Research also indicates it benefits renal function -over 160% in 5 days.
Two gallons of water in 24 hours is over 2x the recommended amount for anyone. No wonder your kidneys got strained. Nothing to do with the fast.
You’re lucky you didn’t die or have kidney failure.
Possibly your problems came because of a total disregard for proper water fasting protocols. The starvation mode comes into effect when you do not rest 24/7 during the fast. This includes physical and mental (computer). activities. Only one half gallon of water is required if you follow correct natural hygiene fasting suggestion. Hope that helps.
The reason I was fasting is that I have been diagnosed with Osteoarthritis…it is in many locations in my body and is causing me a lot of pain and making moving, walking difficult. It is especially in my hands and as I use my hands in my work this is particularly disturbing. It is getting worse very quickly.
i completed a 19 day water fast a month ago. It was very easy for me. I had tons of energy….and didn’t experience any detox symptoms. I have fasted before but for just a few days at a time. I also eat a pretty clean mostly organic diet. The net effect was that I had almost no body pain…leg, feet, back, neck were all so much better. I was able to run for the first time in many years. my digestive problems cleared up completely and still are much better. I have become completely regular.
I came off the fast on a bone broth soup and then added veggies to that over a period of a week. as soon as I started with the veggies the pain started up again….very little but I was worried. I am still eating mostly veggies with some fish occasionally. no grains, very little dairy, no sugars. I tried different types of veggies…but it just seemed to be getting worse. A month later….I have most of the body pain that I had before and my hands are very bad.
I am very interested in fasting for a long period again…it was such a great experience for me…but I wondered if anyone else has experienced this and had a similar reaction. I suggests to me that my pain problem is centred in the foods I ingest. I am currently trying the lectin diet (even though to date there is no clinical proof that it works) to see if that could be contributing. I am going into my third week of Dr Gundry’s diet…and the pain seems to be maybe a bit more manageable ….but stiill not great.
Hi. I am on lockdown in Kenya. I tried a 5 day water fast. No juice no coffee just plain and weak black tea. Sipping water. 3 pints a day.
Hungerpangs were too bad. Ate 5 biscuits after 45 hrs. Then went 18 more hours before eating anything else.
After tonights meal i will start a 3 day water fast. Doomed to fail as i am already hungry.
I am two hours away from completing a 72 hour water fast. I ran into your article because I’m certain one of my kidneys is hurting. I’ve done water fasting in the past and I’m more experienced with 24 hour water fasts. In early 2020 I was re-attempting regular 24 hour water fasts every other week. Back in 2008 I was very consistent with weekly 24 hour water fasts. Also, for about 15 years I do a raw fruit only fast once a week. During those years I slowly gave up animal products. I haven’t consumed meat in almost ten years. I’m close to giving up dairy as well. By November 2021 I will have met my deadline of becoming 100% raw vegan fruitarian. I am mentally prepared for it to a very high degree. I still intend to say on the path of water fasting, but after reading your article and the comments, I better be more careful with the water consumption during the water fast. I read over and over about how one should drink plenty of water during a fast. I’ve consumed about a gallon, really, in the last 72 hours but I’m dry fasting for these last two hours. My left kidney is super achy. It feels like incessant lower back pain. Ive experienced this pain before during a water fast. I don’t feel it too much at 24 hours, but right now it’s burning just a bit. By the way, I simply expect negative remarks regarding this path. We live in a society that overindulges its taste buds and makes food one of the biggest centers of daily living.