I Met A Dry Fasting Nut

When I arrived in Thailand on the 16th of January of this year, my initial lodging for 4 nights was at a hotel near the location of a Digital Nomad conference I was attending. I’d arranged for a studio condo for a month thereafter and within a day or two of setting up there, I met an Australian expat living in the same complex long term.

John turned out to be a dry fasting nut. But the exchanges were fun nonetheless, since he was familiar with most of the Who’s Who in the general Paleo/LC/Keto thing.

Dry fasting is when you not only withhold all food, but all hydration as well. You’re consuming nothing for a period of time. I initially dismissed John, mostly because of his approach to it. Not only was dry fasting beneficial in just a base health way, but it was a cure all, including cancer, et al.

Then I began to think about it, not even having any clue that it appears to have become somewhat of a thing or fad, now. Having just done a water fast of about 60 hours around the same time I met John, I recalled how important water, coffee, and tea (unsweetened) were to “get through the fast.” Then I recalled admonitions like “if you’re hungry, drink glass of water” (the hunger might resolve).

Curiosity piqued, I Googled around a bit and thought even more. I am not one to spend hours listening to what others think. Of course, part of the science on the benefits of fasting is gleaned from the Muslims who, during the entire month of Ramadan, dry fast from sunrise to sunset. In high latitude climates, these no-intake-at-all fasts during May can be be pretty short in the Northern hemisphere and pretty long in the Southern. But nominally, it’s 11-16 hours for most.

I initially experimented with that. I consumed nothing from last intake of either food or fluid for 12 hours or so (12 minimum always). But this was different because most of that is during sleep which is a fast anyway and dry for most of it.

I did a 24-hr dry fast and was rather shocked. It turned out to be, by far, the easiest fast I’ve ever done. There can only be one reason for that: the fluid restriction curbed hunger. Hmmm….

Well, it appears to have been understood as early as 1942 that the body metabolizes fat to create “metabolic water” (water by any other name).

THE utilization by the body of ingested food substances and of tissue reserves yields among other things quantities of metabolic water. As the complete combustion of 100 gm. of fat produces about 110 gm. of metabolic water, whereas 100 gm. of carbohydrate yields only 55 gm. of water, fat reserves and fatty foods are believed to be particularly valuable as a protection against desiccation. This contention would appear to be supported by the fact that many animals which exist in deserts have large reserves of fat.

Nature; Metabolic Water and Desiccation. https://www.nature.com/articles/150021a0

What I found even more interesting is that in just my case alone, the single 24-hr dry fast seemed to equal the subjective benefits I felt from three days of a water fast. Things like clear sinus, large reduction in any bloating or swelling, and disappearance of inflammatory markers like redness. And the pants fit better.

Seems there’s science to it. Beyond the numerous studies that substantiate the benefits of Ramadan fasting, there’s a single study from 2013 that dry fasted 10 individuals for 5 days. The results are nothing short of astounding, in my view.

Background: Although there is considerable research in the field of fasting and fluid restriction, little is known about the impact of food and water deprivation (FWD) on body circumferences and vital parameters. Methods: During 5 days of FWD in 10 healthy adults, hemodynamic, metabolic, and renal parameters, such as weight, 5 circumferences at neck, waist, hip, chest at axilla, chest at nipples, and 1 new oblique hip circumference were measured daily. For each circumference, new quotients of daily circumference-to-weight decrease were calculated. The set of employed parameters quantified and monitored dieting persons’ compliance and efficacy of the method. Results: The values of blood pressure, heart rate, hemoglobin oxygen saturation, glucose, K+, Na+, Cl-, urea, creatinine, and serum osmolality proved to be stable. The mean creatinine clearance increased up to 167%. The mean daily weight decrease (1,390 ± 60 g) demonstrated the effectiveness of FWD in weight reduction. The daily decrease of all measured circumferences and the values of the corresponding circumference-to-weight decrease quotients reflected considerable volume decrease in all measured body parts per day and kg of weight loss during FWD. Conclusion: The intervention of 5 FWD days in 10 healthy adults was found to be safe, decreased weight and all measured circumferences, and improved renal function considerably.

Complementary Medicine Research; Anthropometric, Hemodynamic, Metabolic, and Renal Responses during 5 Days of Food and Water Deprivation. https://www.karger.com/Article/Abstract/357718

The first takeaway is the weight loss. An average of 1.4 kilograms per day over 5 days. That’s astounding. For you people who have to live in America—and not a tropical paradise in Southeast Asia writing on the beach—that’s three pounds per day, or 15 pounds over the 5-day fast. Of course, low carbers and ketos know that a portion is water dump via glycogen depletion because of no energy intake. BUT, and a BIG BUT in my view, is that because there was no fluid intake, it’s quite likely that additional fat was metabolized beyond energy requirements in order to produce “metabolic water.” It’s the latter portion that’s real fat loss, since the water dump will come back physiologically as soon as glycogen is restored to normal levels.

The other big takeaway is “improved renal function considerably.” That, I found nearly unbelievable as it seems well established that severe dehydration can cause kidney damage and in fact, that happened to a family member once, when stranded in a jungle in central America for days. So it raises the question as to whether controlled, low activity dry fasting in healthy people constitutes severe dehydration or even dehydration at all.

Let’s revisit my friend John. It turns out that his search for a cure was because of kidney disease and he came upon dry fasting. He’s gone up to 11 days (after 5, under medical supervision). Ten years later, his health is fine, he looks great for being in his 70s, and most importantly, he reports that his kidneys are at full function, verified by regular clinical testing (which he gets cheap here in Thailand, where people haven’t been priced out of medical services by insurance and drug companies, but I digress).

Look, I don’t pay much attention at all to the cure claims. If they’re there, fine. Try it. My primary interest is in the accelerated fat loss and I suspect, so-called stubborn fat. I’ve seen micro changes in this area, and I’ve yet to go more than 24 hours.

Here’s what I’ve done and I’ve found it simple. I have this crazy notion that while excess hydration can’t make you gain and store fat directly, perhaps it inhibits fat that could otherwise be shed. Wouldn’t it be ironic if, for all the talk of sugar drinks being the root cause of all obesity, it’s really the obsession with hydration at all waking hours, per se? So, one person enjoys a soda sugar drink over the course of the day but otherwise, drinks nothing but maybe a cup or two of Joe in the morning, and whatever other sips are necessary to wash down food, vs. the people who have their hydration bottle near at all times and drink a few liters of completely unnecessary water over the course of the day?

So, for me, it’s a cup or two of coffee in the morning, only sips to wash down meals, and evening cocktails, if any. Nothing else. Zero intake overnight. And it’s easy, and it’s become normal. The feeling of never being bloated with excess is nice. Another factor is that I try to sip as little as possible with a meal (don’t forget: there’s water in your food). This took a few days of adaptation but once there, stomach digestion and emptying is superb. Could it be that excess fluids during meals dilutes the digestive juices and often ends with slowed digestion, bloating, gas, and heartburn?

The other day I went on a 5-island snorkeling trip here in Koh Chang, Thailand by speedboat, from 9am to 5pm. I had a cup of coffee and a small plate of watermelon at 7am or so, and zero intake throughout the day. No food, no water. It was easy. No problem at all. I was in the sun, but also the cool ocean. All the while, everyone else was almost constantly sipping at their water. And the boat crew kept handing them out. And I’m proof that it was all unnecessary. What I’d really like to know is whether I lost a few grams of fat that others didn’t, in order to make my required water.

So there you have it. Lot’s of water for thought, I hope.

Since Covid killed my Cabo San Lucas vacation-rental business in 2021, this is my day job. I can't do it without you. Memberships are $10 monthly, $20 quarterly, or $65 annually. Two premium coffees per month. Every membership helps finance this work I do, and if you like what I do, please chip in. No grandiose pitches.


  1. Dr. G. Moore on March 8, 2020 at 01:34

    As insulin comes down… your urine production starts to increase — and the kidneys are the sight of cleaning the body — your best friend is helping the kidneys to produce urine. And your kidneys start to flush out toxins. Fasting will release fat-bound toxins and facilitate detoxification.

    Ketones are an inverse indicator of where your insulin is — even in a way that glucose can not.

    Having fewer liquids in your system means more fat burning to create metabolic water.

    “The body has the ability to create its own water. Most of the fat that is stored in our body is saturated fat. And saturated fat is saturated with hydrogen. So, when the body is in a dry fast dehydrated state — it takes the fat, and releases the hydrogen, the hydrogen gets in your bloodstream, and then you breathe oxygen and you create water. The purest, most metabolically efficient, metabolically perfect water. Perfect for your body because you synthesized it.

    You’re going to burn more fat in a dry fast. The body is going to continue to thrive on the hydrogen from the fats. The longer you dry fast, the more your body has to dump its hydrogens from the saturated fat.

    The dry fast makes your brain more receptive to ketones through a permeable blood-brain barrier. Higher ketone production on a dry fast.”

    And, HDAC inhibition…

    BOHB, at millimolar levels, is an inhibitor of histone deacetylases. BOHB at 1-3 mM — the range of nutritional ketosis → you are increasing your body’s defenses against oxidative stress. A potent drug like gene signaling effect that protects your body against ROS, oxidative stress and inflammation.

    Histone deacetylase (HDAC) — a group of enzymes called gene silencers (do the work turning the genes in our genome on and off). HDAC (histone deacetylase) activity turns off your internal oxidative stress protection.

    In my daily 20+ hour fast, it’s always dry. Never thirsty. I’ll throw in a 48 or a 72 with varying frequency. At least one 72 a month. Dry.

    I’m starting a 72 hour fast in about 30 minutes (dry). Might extend to 5 days.

    Even on my 6 month Thailand odyssey, I stayed with one meal a day.

    Intense/brief and episodic physical exertion every day. The big four: push-ups, pull-ups, squats and inverted rows.

    • Richard Nikoley on March 8, 2020 at 01:59

      Fantastic info. Thanks doc.

      I’ve really enjoyed Koh Chang. Last night. I’m over at The White Elephant for the Sunday Roast (with Yorkshire pudding). So, no fasting just now. But I leave early AM for Chiang Mai. Travel days are my favorite time to fast, you don’t have to worry about anything.

  2. G. Moore on March 8, 2020 at 07:11

    Cookies Hotel on the left in pink. Banpu just a short 5 minute walk to the south.

    Good point. Fasted travel is the only way to fly.

    • Richard Nikoley on March 8, 2020 at 07:14

      Yea, Banpu is where I stayed. I may have mentioned that. A bit dated but otherwise quite nice.

  3. Lars on March 8, 2020 at 14:24

    Interesting! This reminds me about an article on deuterium and metabolic water.

  4. GMoore on March 8, 2020 at 06:45

    We had a blast on Koh Chang.

    Glad you enjoyed your visit Richard.

    This is what your departure will look like.

  5. Holdem17 on March 8, 2020 at 08:49

    In the literature, carbohydrate used to be called ‘hydrating carbons’. It’s amazing what we forget.

  6. MAS on March 8, 2020 at 09:26

    Interesting post.

    One of my favorite movie genres is Western. I always wondered how the cowboy could travel for hours in the sun without a water bottle. Then as soon as he arrives in town, he gets a whiskey.

    If I ever tackle my coffee/espresso addiction (unlikely), I’ll give it a try. ?

  7. Bret on March 9, 2020 at 15:49

    That really does make a shitload of sense.

    Certainly our HG ancestors developed the ability to endure intermittent food scarcities without having to gulp down water like camels in order to stay alive & functional.

    I’ve always been averse to drinking lots of water, whether during fasts or not. Unappetizing in general, and this could well be why.

    Thanks for sharing. Glad you’re doing well on the new adventure.

  8. Mark on March 10, 2020 at 09:58

    Mark Sisson seems to be of perhaps similar thinking:

    Grok obtained most of his water directly from the food he ate, and I believe that we probably should, too.

    I don’t get thirsty very often. I rarely drink so much as a single glass of water during my normal daily routine. When I was a runner, and later as a triathlete, I would go out for long runs or rides without much water – if any at all. Sure I’d drink a bit to recover lost sweat when I returned home, but if I was riding for less than two hours, or unless it was unusually hot, I didn’t even put a water bottle on my bike. Even today when we take a break playing Ultimate Frisbee on hot Sunday afternoons, I have to force myself to drink sometimes when I might just as easily skip the water altogether. Meanwhile, I see people at the gym with 2-gallon bottles of Arrowhead, fully intent on polishing them off before dinner, thirsty or not. So, am I flaunting conventional wisdom at my own peril? Or am I just doing what comes naturally to a Primal being?

  9. Mark on March 9, 2020 at 22:15

    Perhaps only tangentially related but Noakes wrote about over hydration in endurance sport. Point about movement and hydration:


    We know now that humans evolved this incredible ability to hunt in the heat, and we must presume that they didn’t have access to water because they couldn’t carry much water with them. All they had was ostrich eggs which [they used as canteens and] only could contain a couple of liters [67 ounces]. So we know they had to have run without fluid ingestion. When they killed the animals, they would actually take the water content from the intestines. They would replace their fluid losses by drinking both the blood and the intestinal water content from the animals that they killed. So they had to wait until after they killed the animal until they could drink.

  10. Resurgent on March 10, 2020 at 22:55

    Great post Richard..!
    Besides Ramadan, Eastern cultures are replete with dry fasting. Only that in recent times this process has been taken over by organized religion and made a mess of. The hindu women in India have been known to dry fast once every week on a certain day and men on another day, while there are special days based upon the moon phases and the lunar calendar when additional fasts are done.
    The science behind all this is astonishing..
    Look forward to more from your experiences.

  11. Todd on March 11, 2020 at 19:06


    Chris Kresser mentions not drinking while eating so you don’t dilute stomach acid seems to be a mechanism in GERD/heartburn.

  12. G. Moore on March 15, 2020 at 10:19

    I did a 48 hour dry fast last week. Urine color ‘straw’ to clear and odorless.

    A 22/2 dry fast every day.

    48s with varying frequency. At least one a week. And I throw in a dry 72 occasionally to pop the top on the glycogen reserve, i.e., deplete it → and then upregulate some of the ketogenic enzymes to start mobilizing fatty acids.

    BTW, if it takes 24 hours for ketones to reach up to 0.5 mM, and the beneficial threshold is 1 mM, it suggests there may be a dosing problem with some forms of fasting. This raises the possibility that the metabolic switch isn’t occurring in some types of TR.

  13. Derg on March 15, 2020 at 02:34

    Richard when you don’t drink much does your urine become dark yellow and pungent ?

    I wonder what causes that?

  14. Mycroft Jones on March 15, 2020 at 15:13

    1.5 kilos a day. Wow. A 200 pound male might carry 1.5 kilos of glycogen; so any weight loss after that is depleted is probably pure fat loss. Inspiring post, thank you Richard. I wonder if this explains why the potato hack works; calories in, calories out revealed to be a fraud. Potato starch needs water to break it down. But that doesn’t explain why potato soup is so good for weight loss.

  15. Drew on April 19, 2020 at 01:52

    Interestingly I did a Chinese herbal diet and the first two weeks it was no food, about 80ml of liquid herbs three times a day and a max of a very small glass of water to be sipped total. After a few days it was easy, just strange. 30kg in 10 weeks, not ideal but effective. You’ve inspired me to do some potato intervention with minimal water to hit the next 20kg. Cheers mate

Leave a Comment

You must be logged in to post a comment.