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Fasting for 15 Months: Retrospective Observations

Contributor Bio

Alex Tarnava is the CEO of Drink HRW, and the primary inventor of the open-cup hydrogen tablets. Alex runs the clinical outreach program for our company, working with over a dozen universities coordinating research. Alex has also published research of his own. You can find it on his ResearchGate. Additionally, he has been interviewed for many prominent publications, such as Entrepreneur and Forbes, and on many popular Podcasts. You can find all of his interviews and articles on his media page.

Fasting for 15 Months: Retrospective Observations

As I set out with my new series on biohacking and its potential benefits, I have decided to reflect on the pros and cons of one of the health routines I have been the most dedicated to over the last 15 months: water fasting. I first wrote about the potential benefits of fasting last year, which I began looking into and experimenting with in April of 2019, and wrote an update article on how fasting was becoming easier in the late summer and fall of 2019.

I would say that fasting has now become even easier than it was before, almost effortless. I fast for 42-48 hours twice a week, an “upgraded regimen” I began in November 2019, previously fasting 42-48hrs once a week and 72hrs every 4th, opting to skip eating on Mondays and Wednesdays. Once every couple of months, I will fast for 66-72 hours instead of for 2 days of 42-48 hours, and I have also committed to a 5 day, ~110-120 hour fast annually, which I have just completed, breaking my extended fast a few hours ago. It is no longer a struggle to fast for ~48 hours; I do not even think about eating. I have no issues watching others eat. For ~72-hour water fasts, I have limited but easily subdued cravings. This last ~120hr fast was an interesting experience. After 86+ hours, my cravings were intense, and my energy rolled in waves, but I had no issues pushing forward and completing it. At no time did I doubt my ability to make it or consider stopping short.

This fast also showed some adaptations for me. I have long had no nausea or stomach issues on breaking a 48, or even 72 hour fast. I was curious on how my stomach would handle the 110-120 hour fast. I broke the fast with some high fiber wraps (bean sprout wraps) and light hummus (no oil). I felt fine. Then, a couple hours later, I had a fruit and vegetable smoothie with some almonds added (no juice or sugar added, water as base). Again, I felt fine. Shortly after I had another bean sprout wrap with some more hummus, then waited and had dinner, a large tuna poke bowl. Again, I felt completely fine. No nausea, and at no point did I get a warm sensation or high from a sugar rush. I decided to really press myself and made this night my “dessert” night, eating ice cream and chocolate fudge. I am quite curious by nature, and assumed this was a mistake, but wanted to see anyways. Shockingly, I had no ill effects. It did not give me a sugar rush, and did not upset my stomach.

This fast also allowed me to experiment more with exercise while in a fasted state. I completed a heavy bag work out each and every day. As usual, I had no performance decline within the first 48 hours. My work outs at hour 67 and 91 were progressively declining, down to 60-70% of expected output. I had to work out early on the final day, at hour 110. It was a train wreck. I
needed to quit half way through, and had no power of stamina. In an actual fight I would have been completely defenseless. When I woke up the next morning I was so sore with my muscles so sufficiently sapped, I had a hard time getting out of bed. I could not reach for a glass to have some water as my arms wouldn’t lift high enough, I had to drink from the tap. I was shuffling around barely able to walk, and drew myself a bath to try to save myself with a hydrogen water bath. Attempting to lower myself into the tub, my muscles gave out and I slammed down. Interestingly after a 30 minute bath, admittedly using 6 full bottles of H2 Relief, I felt a little bit
better. I could walk, but not really jog. I could get a glass from the cupboard, but later that day had to take a break carrying groceries inside. Importantly, the intense pain I had even while immobile, especially in my shoulders, was only present when the muscles were working. Next time, I think I will skip the workout on the final day.

So, fasting has become easier… but are there any benefits to it? Do the benefits for my own health outweigh the negatives, and the effort? That is what I am set on determining.

Observational Benefits

Fasting glucose

My fasting glucose quickly dropped to 4.1-4.3mmol, or 74-77mg/dl for US readers within the first few months of my fasting routine. This is great, as my fasting blood glucose was previously hovering over 5mmol or 90mg/dl, not yet in “metabolic syndrome” territory, but on the high end of normal. Even after a day of binging on pizza and wine, I do not go above 4.6-4.8mmol or 83-86 mg/dl. It also quickly returns to baseline after a day or two of healthy eating. My fasting blood glucose has become so consistent I have stopped checking multiple times a week, moving
to weekly, and now moving to once or twice a month. It has been rock-solid.


When I set out to clean up my lifestyle, shortly thereafter starting fasting, my weight had become a problem. I was in metabolic distress, weighing 267lbs and eating ~2200 calories a day, without losing weight. Years of poor eating, working 100+ hours per week, poor sleep, and excessive drinking had taken their toll. It was easy to not work out since my chronic injuries are so severe. I kept justifying the situation to myself, thinking, “After I get surgery, I will get back into shape,” and finally realized, after facing the necessity of buying a new set of clothing yet again, that this future internal “deal” was not a healthy option. When I wrote my update on how fasting had become easier, I was down 37lbs. In the many months since, I am down another 10lbs to weigh 220, the lightest I have been since Christmas of 2014! Of course, there are many different types of body compositions, and importantly, mine
has improved.

Body composition

When I updated everyone on my fasting protocol, I was still rehabbing post surgery, had not exercised in months, and had lost considerable muscle mass. MRI results and assessment has let me know that during rehab, I partially tore the long head of my bicep tendon, something I believe I repaired with my self administered BPC-157 protocol I wrote about here. Since starting this regimen, I have been able to kick my training back up significantly. Actually, even before implementing the BPC-157 regimen, I had decided to do everything I could to gain back muscle mass. In September 2019, I weighed 218lbs, continuing my weight loss. My physiotherapist and I devised work out plans to avoid using my shoulder, focusing on two-dimensional workouts using machines, with body weight and functional movements leaning to a heavy focus on my legs. My weight started creeping back up with exercise, and shot up more aggressively in December of 2019, when I restarted several exercise-focused supplements, such as creatine and beta-alanine. After those additions, my weight crept up more, peaking at 243lbs.

I found that my pants fit around my waist, tightening in the thighs, and my shirts became too short, and not too tight around my midsection, from growth in my back. Since the peak of
243lbs, I have dropped 23lbs to date, from early March 2020 when the lockdowns began, until the time of this writing in early June of 2020. One thing that has been critical in maintaining the muscle mass while aggressively dropping weight has been my willpower, which I directly credit fasting for.

I used to need a goal in order to follow a diet, such as an athletic accomplishment, or something to that effect. This led to my weight yo-yoing throughout the years. In my 20s, I would routinely gain or lose 30lbs in a month. When I had no “focus,” I would eat whatever I craved, partying and doing damage to my body. When I had a goal to focus on, I would shut down all this behaviour and obsessively control my diet, and training. At some points, I would train 6-8 hours a day, 5-6x a week, leading to negative health consequences from excess exercise-induced stress on my body. Since sustaining my injuries and developing permanent issues, I have been unable to have a “goal,” as there is nothing I can compete in. As such, I have had a very difficult time controlling my diet.

I realized that even with my fasting, and eating healthy on Sundays, Tuesdays, and Thursdays, for the day directly before, and after, my fasts, yet binging both Friday AND Saturday, I was curbing any future improvements in terms of excess fat loss. I was also drinking far too much. Before some incidents that happened when I disregarded my own “no alcohol after a fast” rule, I was drinking 3-4x per week, each time consuming 1-2 bottles of wine as a minimum. After my tolerance significantly declined, I was still drinking half-bottles 2-3x a week, and full bottles or more 2x a week, often drinking within hours of breaking my fast.

This drinking, and the fact that I was not at all limiting myself on dietary intake on Fri/Sat, lead me to create a lifestyle plan in April. Only once a week could I eat whatever I please. Only twice a week could I have wine; only once a week could I have a dessert, and also, once a week, I could have some "intermediate" options such as cheese, white pasta/bread, dips other than light hummus or tzatziki, etc. I've never been able to moderate like this, but over 2 months in, I have had no issues. I plan out my "treat" days ahead of time, look forwards to them, and follow a strict diet on the "normal" days. What's more, as I am getting into the groove, I am significantly cutting down on my cravings and desires for these treat days. Some weeks, I have not had any wine, for instance, or skipped dessert, etc. I am trying to make sure that I do have some sort of treat every week, as I know myself, and know that if I go "all in," some event could lead me to stop completely. For the first time in my life, I can eat "treats"every week, and limit how often I do it. Fasting, and the mindset it has brought me, has had an incredible impact in this regard. This impact alone, I feel, makes the practice worthwhile for myself and countless others; so long as they gain a similar change in mentality.

As I alluded to above, I like(d) to drink. I drank often, did most of my writing after 2 bottles of wine, and had no regard to any potential deleterious effects. Actually, in a retrospective analysis of my sleep from a year ago, except for the nights that I know I was blackout drunk after attending events such as weddings, etc., I cannot easily detect any deleterious impact on my sleep from my habit of drinking multiple times per week, meaning any changes are not so obvious as to not need an analysis.

My drinking, previously, led to little takeaways on any stressful impact. Up until about 6 months ago, a bottle of wine consumed over an hour would register me at a 0.00, or a 0.01 BAC%. Two bottles of wine over 2hrs would spike me at a 0.02-0.03. I tended to go to bed dead sober, even after two bottles of wine. I enjoyed it, and when I hovered in the 0.02% range, I found I was least inhibited by my daily stressors and anxieties; it also let me be more creative and write more content. I am not going to lie, writing now, without alcohol, has changed from being a passion to a chore. This is not to say I do not enjoy writing at all, but more that I find it much
harder to get into the state of mind needed to write.

That all changed in early December of 2019, at a Christmas party/client appreciation event with an open bar. I was coming off a fast and having consumed no calories, and only ~2000 calories in a 120hr period, having done a 72hr and then a 48hr fast in anticipation for Christmas festivities, and I intended to feast on the ample spread at the party and abstain from the wine. Upon arriving, there were opportune business discussions far away from the food, and beside the bar. Justifying a single drink before I ate, due to my believed tolerance, I made a truly
terrible decision. That night unraveled and I did not end up eating, only drinking, through the party and into an “after party.” I have never been so ill following alcohol, and to this day, do not have anywhere near the same tolerance. In fact, I am now conducting a double-blind and placebo controlled observational study on myself and on my spouse to examine the impact of alcohol on sleep quality after low, moderate and high intake of alcohol, and how the hydrogen tablets impact them (the double-blind placebo controlled part). I can officially say that consuming half a bottle of wine leads to similar BAC% readings as 2 bottles of wine did for me
previously. What’s more, I now become hungover when consuming what I consider low amounts of alcohol, such as a bottle of wine, early in the evening 6-7 hours before sleep.

Clearly, my body is responding very poorly to having consumed large amounts of alcohol after fasting. If you are thinking of fasting and enjoy casual drinking, I cannot caution you about these observed effects seriously enough.

One very notable and very significant health decline that has happened for me has been my blood pressure. My blood pressure hovered around 100/70 a year ago and was creeping up to 110/80 before the incident in December of 2019, which is still a healthy reading. I attribute this slight increase to my muscle gain from training again. More mass leads to higher blood pressure, at least in the short term.

That said, since I started restricting myself in April, or since my last almost daily reading of BP in March before the lockdown, my blood pressure has shot through the roof. I purchased a blood pressure monitor for home use for the purpose of some of the n=1 and n=2 observational and controlled ‘biohacking” studies I am doing, and was shocked at the results. My BP averages in the 135/80 range, with my HR in the 80s. In March, it was still typically 110/80 with a HR of 60. This is a very large increase in just 3 months, during which I have dramatically improved my
diet, lost 15lbs and quit drinking.

Is the fasting to blame? Probably not, but maybe indirectly. Chronic drinking can lead to higher BP, but what about consumption of alcohol insufficient to reach intoxication? Based on my typical drinking having little impact on my sleep, and nominal impact on my BAC%, etc., was my drinking habit positively impacting some health markers? I wrote about the science backing the potential of ethanol as a hormetic aid here, and like any hormetic stress, the dose makes the
poison, or benefit. For me, I have some extreme reactions to various stressors. As I discussed in my article on cold exposure I can walk outside in -10c weather in a t-shirt, and can hold a conversation while in a cryo chamber. On the opposite side of the scale, heat exposure absolutely wrecks me. I easily get heat stroke, and have had horrible bouts of extreme illness after just hours outside in hot weather, conditions others handled with no issue. I have had very dangerous encounters in saunas, and cannot make it through a hot yoga class. Hormetic stressors will be very dose, and person, dependent.

Did changing my tolerance for alcohol disrupt the possible benefit I was receiving from alcohol? It may have, and if it did, fasting is partly to blame. I am considering adjusting my schedule to drink 1/2bottle, or if out at a restaurant a single 9oz glass of red wine, in the early evening Thursday, Friday and Saturday: but only if I have already had a meal. I won’t be able to attempt this for another 3-4 months when I complete my study. Observing any changes to my health markers may tell a better story.

Fasting has come with numerous observed benefits, and some perceived dangers, largely due to my own actions. All in all, I am happy with my routine, and believe that it is a great tool for health. I will continue tweaking and modifying, studying my own sleep, blood glucose, blood pressure, and soon, body composition (scale on order). Only by retroactively recording where I was previously, can I determine whether I am improving. In the future, more measurements will be added.