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Breaking the prolonged fast - sluggish insulin release?

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Hello! I just broke my first > 32 hour fast. I ordered FMD ProLon package as a "backup" but I ended up doing the full 4-5 day fast on water alone.

 

I read that digestive enzymes may take a little time to wake up and considered soft veggies / fruit to break the fast. But I was traveling and it was easier to just use ProLon to break my fast. I figured since it is formulated to allow autophagy while fasting it on the face of it should have a modestly low glycemic load and be fairly easy to digest.

 

So to break my fast I ate in one sitting:

1) the entire day one ProLon package except for the 90 calorie choco crisp bar ( so

2) one medium banana and one medium orange

 

Now I realize this may sound like a lot of calories since the ProLon package for day one is meant to be divided amongst 3 square meals. However this seemed very reasonable and modest since I have had good blood glucose control ( on days I only have one meal) having 3000-3500 calories in one sitting with no problem.

 

The FMD day one kit, According to https://www.google.com/amp/www.telegraph.co.uk/wellbeing/diet/why-weve-all-been-doing-the-fast-diet-wrong/amp/day one has 1090 calories, so minus the 90 calorie snack I didn't eat, but and adding the medium banana and orange I had probably around 1,167 calorie so the meal still represented only around 1/3 of my regular meal size I have with good glycemic control... and with the prolonged fast my muscles have all their glycogen depleted too.

 

So here were my results ( after my first elevated reading I tried a few miles of walking and a bit of anaerobic exercises, so the blood glucose values could have been a lot higher):

 

* Baseline biometrics before breaking fast (2:30am): BG 69, ketones 1.9, temp 97.19.

* Broke the fast @ 3:35am, completed meal 4:15, eating slowly while running a few errands.

* BG 170 @ 4:40am( repeat at 183), ketones 0.6,

* BG 178 @ 5:30

* BG 183 @ 5:45

* BG 165 @ 6:35 ( a little over 2 hours after completing the meal so pre-DM range)

* BG 164 @ 7:15am.

* BG 154 @ 8:30 ( after nap, now 4 hours 15 min after I finished the fast-breaking meal)

* BG 121 @ 9:20 ( 5 hours & 5 minutes after finishing meal).

 

What strikes me about those numbers are not how high they were - I normally have very low glycemic load whole food based meals rather than packaged foods, and I recognize that having a low BMI increases peripheral insulin resistance and perhaps it takes a extra time for the pancreas to wake up and secrete insulin following my prolonged fast. Rather, what strikes me is that despite all my muscle glycogen being depleted and exercising on and off while taking measurements throughout my logs above ( & exercise usually works like a charm), how very long my blood glucose remained elevated, for hours on end. I have never seen this before!

 

I looked at the ingredients in the L-nutra ProLon packet for insight on contributing favors for the highly elevated blood glucose and the following struck me:

 

* the L-bars ( photo attached) had honey with 13 g of carbs of which only 3 g was fiber... these were 280 calorie bars and I had two of them so they comprised a fairly large part of the estimated 1,167 cal in my meal. I was surprised in retrospect how high simple sugars these have:

 

* The dried reconstituted soups ( I ate two of them) were not especially high calorie ( 120 cal for tomato soup, and 130 calfor the ministrone soup) however first three ingredients for the minestrone were potato flakes, rice flour, & potato which In hindsight I would expect have a decent glycemic load ESP as they are in dried form

* The other contents ( kale chips, olives) looked benign though I am sure addition my orange and banana contributed a bit

 

( addendum- insert said 1150 calories for day one, ~800 for following days which was pretty close)

 

I am wondering your thoughts regarding much of this highly prolonged blood glucose is pancreatic delay vs the contents of my diet? I also am pondering the adverse effect of this as a side effect of prolonged fasts.

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Edited by Mechanism

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Well let us know how it goes with your normal food. However I would say that last year when I did an extended water-only fast for the first time, I also experienced some elevated glucose readings afterwards. However it was hard for me to decipher as at the time I was using a slightly unreliable meter combined with happening to just switch to a fresh set of test strips after the fast, and on top of that over-eating calories for a few days after the fast. It did seem that after 4 or 5 days my readings settled down.

 

Part of the issue may be just how much of your body can fat-adapt to feed off ketones. May take a little while for it to switch back to glucose?

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Congratulations mechanism for the completion of your fast!

 

RE: blood sugar, it might be pancreatic delay, it might be gastric delay after a long fast, coupled with a high glycemic meal, all together would have contributed to the extended high glycaemia. 

 

It didn't occur to me to measure BG after my FMD. I just noticed that fasting BG counter-intuitively increased slightly during the FMD (from 78 to 84 mg/dl) whereas returned to the initial value (79) on the 6th day. It didn't decrease, maybe an example of nearly perfect homeostasis.

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The somewhat low 1.9 for ketones after 5 days of fasting might indicate that you had very effectively switched over to burning ketones and largely switched off glucose metabolism.  It's well documented  that people in such a state need time to reestablish the enzymes of glucose metabolism.  Generally it's suggested to take 3 to 5 days of ramping up carbohydrate intake to get accurate testing of glycemic control / insulin sensitivity.  For most people cycling glucose metabolism down and back up results in an improvement after the cycle is complete.

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It was a very interesting experience, my first with a real prolonged fast.  Now I can relate more to the experiences of Sthira and others here for whom this is part of a way of life.  I have more reading / research to do to decide for sure whether I will repeat, weighing the pros/cons of doing annually, for both health and spiritual purposes ( it is great when they can be combined!).

 

BrianA - yesit is interesting you have had the same experiences.  I have not delved into the basic science and validity of it, but I have come across the concept of "metabolic flexibility" wherein utilizing a pathway that mobilizes one macronutrient over another increase the speed and perhaps efficiency of subsequent exposures to that macronutrient.  Ie, if you are accustomed to utilizing ketones more frequently you adapt and change faster when required for that fuel source.  This may (and conversely less frequent or more remote utilization of the pathway reducing the speed/efficiency) relate to your hypothesis.  No great controls here and I suspect with the 5 days being short on a metabolic timescale, a lot of it was that the FMD packet may be effective spread through the day, but having the whole thing to break a fast is a horse of a different color and imposes quite a metabolic load.  For good reason I htink in the insert they caution for their glycerin drink ( which I did not have) to sip throught the day and not save up meals and take together.  The package does what it says and was well-studied but looking at the grams of simple sugars and raw ingredients ( e.g., rice flour) if taken together is likely to impose too high a metabolic load.  

 

But I think you are right, the other side of it is as I speculated in my original post there are likely delayed hormonal pancreatic paracrine (eg insulin) as exocrine (enzyme to digest foods etc) effects after a fast that amplified the above.  I have not read about the subject but I expect there is a deep literature on it and perhaps something to look into in the future. 

 

I've also wondered about the accuracy and reliability of glucometer readings.  I use accu-check for its reliability (though pay a pretty fortune for those expensive test brand-name strips) and when I question accuracy I take a second strip right after and repeat to get a sense of variance and under similar conditions it has proven reliable.  There was on old thread circulating somewhere on optimal technique for testing, for example not forcefully expelling blood for the sample but at most gently coaxing it.  I also run my hands under warm water and dry thoroughly prior to use.

 

mccoy - thank you for the contrats!  It was a neat experience, certainly an interesting and you learn new things about yourself and what your physiology can/can't do.  No matter how much I read about hey you can only lose say around a pound a day, before the exercise a part of me subconsciously pictured the stigma and fear of emaciation, starvatoin, - deeply ingrained steriotypes and evoluationary associaitons as a prerogative for survival.  Like so much of life it a mind over matter thing,  I never imagined myself skipping breakfast, followed by having one large daily meal ( this one still an experiment for me, in contrast I don't see myself having breakfast for a while), and now, a 4-5 day complete water fast.  Fascinating how we adapt.

 

I do find it interesting that you BG went up on the system.  Because nutrition is so customized I wonder whether you have or would consider following your biomarkers before or after the fast?  Longo's work was based on the premise on average the group as a whole saw statistically significant improvements in biomarkers - at least temporarily.  And if these last ( which Michael R will point out has yet to be shown lest of all they also work independently of CR which remains to be definitively demonstrated), terrific.  But not every participant enjoyed equal benefits and in his own work he noted CRP went down on average only for the participants who had above average CRP to begin with.  Not only does this point mean a healthy group of individuals such as CR members in general may have less to potentially beneift, but it also is a reminder everyone's response is different.  I know you know this better than anyone - you have been a health conscoius pioneer for many years and I enjoy your contributions from all that great experience.  But I'm wondering whether you may have a different response ( neutral or possibly even adverse) than average with regard to other potential biomaerks benefits if you are noting this consistently and believe in it.  I am just throwing it out there as a point of inquiry.

 

The more I read, the closer I come to Michael's caution ( but not conclusive) regarding whether or not prolonged fasts mediate positive effects net of any benefits from short-term caloric restriction.  There is the risk of adverse effects too, especially as this is less well established.  Having said that, notwithstanding the uncertainty at this point in time, I continue to explore potential ( roll of the dice ) benefits exceeding risks annually as at this frequency potential harm is mitigated greatly.  Besides the multiple benefits I listed before relative to traditional CR ( enabling yourself to maintain more of a physique that goes with society's expectations and other quality of life issues, potentially better preventing sarcopenia ), for individuals who are either unable or unwilling to undergo formal CR a multi-day intense fast may promote a degree of autophagy greater than the cumulative impact and/or have significant incremental benefits beyond an already established practice of daily intermittent fasting.  I have not seen any direct comparison, though I would be very interested in reviewing them as autophagy is my primary interest.  As for the longevity debate, I am less concerned with this personally as I would describe myself more focused on morbidity-avoidance interest than in the delay of demise camp.

 

Todd- How interesting - they way I looked at it, since my BG was far lower than usual was still in the middle range or slightly above for individuals undergoing a 5-day fast, was that since I was undergoing limited ketosis and my liver and muscle glycogen must have long been depleted, that rhabdomyolysis - ie, catabolizing my own muscle - was a major source of gluconeogenesis to sustain my adequate blood glucose.  I had a DEXA performed within the last year that evaluated me for percent body fat - I weighed only a little more prior to my fast and it found me to only have 4.6% body fat - comparable so I am told to what professional bodybuilders have ( though I do not look like a bodybuilder!  I still look skinny, but much less skinny than from my pre- weight-resistance days when I was almost 15 pounds lighter! - weight resistance workouts have been my key to keeping my weight up and it looks like much of my gains was just building up some muscle).  In any case, I suspect part of the picture is I just don't have that much fat to burn and, in addition possibly less "metabolic flexibility" to mobilize the limited fat I have to burn as well.  Is that what you were getting at?  I trust the numbers, I used precision Xtra strips.  In theory I should have made the transition faster than most.  IRC, I listened to a podcast not long ago on the results from a randomized trial involving ketosis for cancer treatment that noted his subjects before the intervention ranged from ketones of 0.04 to 0.4.  Mine had ranged from 0.1-0.3 (and a couple readings of 0.4) so for a pre-fast baseline, this is quite high.

 

PS - to all (actually, anything above really directed to everyone, highlighted the names to help out some who replied already) - BG has been basically normal after staying away from anything packaged ( my usual ritual), which is no small task to do while traveling in Orlando.  Today dinner was at wholefoods buffet. If anyone is around would be happy to text me, I'll be back home Friday but attached a couple days for R&R here to business conference that brought me to the area.  

Edited by Mechanism

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Thank you for generously sharing your experience, Mechanism! I think any communication about what we're experimenting with regarding aging, diet, fasting, CR and experimenting is valuable, if anecdotal.

 

* Baseline biometrics before breaking fast (2:30am): BG 69, ketones 1.9, temp 97.19.

* Broke the fast @ 3:35am, completed meal 4:15, eating slowly while running a few errands.

* BG 170 @ 4:40am( repeat at 183), ketones 0.6,

* BG 178 @ 5:30

* BG 183 @ 5:45

* BG 165 @ 6:35 ( a little over 2 hours after completing the meal so pre-DM range)

* BG 164 @ 7:15am.

* BG 154 @ 8:30 ( after nap, now 4 hours 15 min after I finished the fast-breaking meal)

* BG 121 @ 9:20 ( 5 hours & 5 minutes after finishing meal).

One thing Longo's work suggests is that adverse effects from FMD were higher after completion of the first cycle compared to those during the second and third FMD cycles.

 

But you water-only fasted for five days.

 

So if you're coming off a high calorie diet eaten frequently, like typical three meal per day societal routines, I'd agree with Michael that suddenly lurch-fasting for five days yikes might shock the monkey:

 

https://youtu.be/CnVf1ZoCJSo

 

We get better with practice.

 

Regarding your high sustained blood sugar numbers post fast, perhaps this is what shocking the system looks like in the blood sugar kingdom?

 

You could try easing first into this practice by skipping meals, eating fewer calories per meal, and then extending time between meals. Then maybe take a random Sunday off from all food. And so forth. Go slowly, carefully, mindfully -- to me this is one of the major benefits of fasting, the mindfulness and eventual ease. Then it becomes fun to fast -- a joy that's additive to an already rich life.

 

Many of the initial hurdles are psychological (at least for me) and social (pressure to eat from others) and the weight loss.

 

But for me weight has now stabilized at 140-150, I'm athletic, I've fasted a lot, I'm averaging about 30% CR via the fasting route here in 2017, that's up from 25% CR in 2016. I'm also much more muscular by fasting -- my abs are ripped, my core strength surprises me now, I can do things with my body now I just couldn't do when practicing daily CR a few years ago.

 

Refeeding after prolonged fasting with green smoothies works well for me. And I eat fruit, too, duh: it's DELICIOUS those first few days returning. Taste buds are definitely improved, if nothing else: this, these sharp taste buds now. My sense of smell.

 

Also consider buying a water bottle, a straw, some apple cider vinegar, and drink it during fruit refeeding after prolonged fasting.

 

Tl;dr: we get better at fasting with sustained practice. It's like learning to play the piano or pirouette -- we done starts off stumbling like clumsy folk, we do get better with technique and skill, and the body becomes more familiar and adept with what we're asking it to do.

 

And what we're asking it to do -- stop eating -- is something it's been doing through our lineages for millions of years. So, our bodies know stuff our rodent studies do not.

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Hi Sthira,

 

It was my pleasure sharing. I have learned so much from the experiences, research, and perspectives of others here. Thank you for sharing your experiences, tips, and encouragement too - How tall are you if I may ask ( gauging a sense of BMI)?

 

I agree with you, if I prolonged fasted regularly then I think it is very likely I would have transitioned faster on/off. Hard to say for sure how much of an impact on glucose tolerance; I suspect most of it is peripheral insulin resistance, common with low BMI individuals, coupled with the glucose load of the first meal. If I go ahead and make this a regular practice, I definitely plan for less of a glucose load the first meal. The insert for FMD says avoid "binges" for the 1st 12 hours.

 

I do sort of skip meals already: I practice intermittent fasting skipping breafast daily, and have lately experimented with lunches some days too. So for my dinners I while high calorie to compensate after a lot of N=1 "quantified self" experiments with lower glycemic load meals along with exercise, etc. I have been happy with my average blood glucose levels following the meal. Having the meals earlier in the day is ideal but this fits best with my lifestyle and I also try to have early dinners to optimize compatibility with my circadian rhythm ( insulin sensitivity being highest in the morning). Yes, the social/psychic aspects are by far the most significant. During the fast it was good to remember the data on limited weight loss expected in 5 days and see for myself with glucometer readings indeed my body was smart enough to make the metabolic switch to burn exclusively fat and muscle when it needed to :). It was a little like running my little triathalon ( just a sprint one ) - yes, the sensations are normal, no my body is fine, and yes, my body can handle it no problem without significant concerning adverse effects. Hearing your & other experiences with fasting also helped!

 

So next round green smoothies perhaps ( no added sugar), or better yet soft cooked vegetables and some fruit I think are ideal. I was traveling so implementation was suboptimal but next time I can bring it with me and/or make other preparations. I love the ACV idea and indeed incorporated it into the following meals ( which were fine) as soon as I got my hands on some - love the attenuation of GI effect and it is a regular staple for me.

Edited by Mechanism

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Nice find BrianA! It never ceases to impress me how marvelously adaptive our metabolic machinery is. That being the case, I think this is a good reminder for many interventions - in the adage of the geriatrician for optimal medical titration - "start low, and go slow" to permit time for these homeostatic mechanisms to kick in. This, with a balance of appropriate and beneficial stressors ( hormesis / exercise, temperature, etc.) have biological plausibility as "working with the body" and may comprise part of a framework for successful health interventions, especially where research and empirical data are relatively scarce.

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Hi Cloud! Btw, love your user handle, I always think of a sunny day with a few puffy cumulus clouds when I read your contributions... ( but maybe I should be thinking cloud computing with this tech savvy croud)

 

Thank you for the link to Dr. Klapper's presentation. It looks like a very helpful overview of the fasting process. These overviews - both medical and psychosocial in nature are invaluable as most communities have limited individuals experienced with prolonged fasting, lest of all clinicians and researchers working with large cohorts of fasted subjects, which provides a helpful perspective on the range of different responses, and optimal care across a physiologically diverse community.

 

I have gone through some of Dr. Alan Goldhamer's talks and publications before, which looks like it shares similarities with Dr. Klapper, also at TrueNorth. In your video, I found his tips on breaking a fast ( slowly sipping juices over the first hour) a helpful adjunct to the other tips from Goldhammer and others. How did you learn about Dr. Klapper's work?

Edited by Mechanism

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Hi Cloud! Btw, love your user handle, I always think of a sunny day with a few puffy cumulus clouds when I read your contributions... ( but maybe I should be thinking cloud computing with this tech savvy croud)

 

Thank you for the link to Dr. Klapper's presentation. It looks like a very helpful overview of the fasting process. These overviews - both medical and psychosocial in nature are invaluable as most communities have limited individuals experienced with prolonged fasting, lest of all clinicians and researchers working with large cohorts of fasted subjects, which provides a helpful perspective on the range of different responses, and optimal care across a physiologically diverse community.

 

I have gone through some of Dr. Alan Goldhamer's talks and publications before, which looks like it shares similarities with Dr. Klapper, also at TrueNorth. In your video, I found his tips on breaking a fast ( slowly sipping juices over the first hour) a helpful adjunct to the other tips from Goldhammer and others. How did you learn about Dr. Klapper's work?

Hello Mechanism, sorry for my late replying to your kind email. I have not so much time unfortunately.

My nickname comes from my interest in zen where often there is a reference to 'cloud'. a term used to name monk is 'unsui', literaly cloud-water.

I don't remember how I did find the dr.Klapper video, but is the best thing on fasting I found. he and Dr.Goldhamer work at the same center and they have a lot of experience on fastings. Luigi Fontana group has started a collaboration with them to collect their data

on fasting to be analized. 

all the best!Cloud

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I'm currently on day 7 of a ten day fast. It's going very well for me -- loads of positive energy. I'll break it in a few days with veggie smoothies and maybe some fruit like watermelon.

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Thank you Cloud for the tip, the temple looks beautiful!

 

Sthira- enjoy your fast and post-fast meal, you are almost there... no post-fast sadness allowed. :)

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I broke my ten day fast today with some watermelon, and then later an avocado. I felt like I could fast for much longer; restraint, holding back, ending a fast seems more challenging than something as dopey as mere voluntary hunger. Hunger isn't the problem, either, hunger quickly goes away on day two, sometimes even day one, the problem (for me) with prolonged fasting is weakness, despair, then too much joy, love, and happiness (also a problem here in my world).

 

Most of the world's people remain in a constant, unchosen state of hunger and malnutrition -- even the obese striken with poverty and unfairness -- when I fast, though, I dedicate my practice to all sentient beings who must suffer. Not just poor people -- the world's animals and plants rapidly going extinct whom I feel so utterly powerless to help cherish and protect. Not that my fasting for anyone or anything matters very much; but the "spiritual" component to fasting arises naturally, like the salty breeze, even for us atheists. I'd like to believe I'm fasting in revolt against all that's so tragically fucked up in the world -- yet I know my idealistic sentiments are useless and absurd: In U.S. Restaurants, Bars And Food Trucks, 'Modern Slavery' Persists - NPR

https://apple.news/AqtBAHXfsQQOgK74LNBaCQQ

 

The paths out of sentient suffering won't be found in spirituality, god is dead; the paths out will be slowly unwound by that massive machine the scientific method, until that's replaced by AI, then all bets are off.

Edited by Sthira

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Sthira, watermelon is excellent to break a fast. I find watery fruit is perfectly rehydrating, even more than pure water.

 

As to atheism and trust in science i find that it implies as significant a leap of faith as the belief in a supernatural being (God). My reasoned conclusion is that, in probabilistic terms, there is far higher likelyhood that life has been seeded by a supernatural Intelligence (not an AI) rather than life, and all universe, started on their own.

 

Either ways, I agree that our ethical duty toward the social problems which are afflicting our society remain.

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Mechanism, did you continue checking your blood glucose, either fasting or post prandial, since your elevated post fast readings?  I'd expect it would have returned to normal in a few days. 

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Todd, by a few hours later BG returned completely normal. Indeed, out of curiosity I checked a panel of labs just under 8 hours after the meal that broke my fast. Technically that lab regards 10-12 hours as fasted values and I even snacked on a few veggies after breaking the fast and before the lab draw.

 

In Valter Longo's follow up publication to the original FMD study he found modest elevated liver function tests @ 1 day following breaking the FMD. --- I believe it was in the supplemental appendix of the extended PDF file --- can't find it right now but would be the supplement to this I think: https://www.researchgate.net/profile/Stefano_Di_Biase/publication/313781104_Fasting-mimicking_diet_and_markersrisk_factors_for_aging_diabetes_cancer_and_cardiovascular_disease/links/58af0f99aca2725b54111cc2/Fasting-mimicking-diet-and-markers-risk-factors-for-aging-diabetes-cancer-and-cardiovascular-disease.pdf

 

I therefore was curious regarding the extent of inflammatory toll taken from breaking my own fast - though as noted I checked at 8 rather than 24 hours and off the top of my head I don't know how many hours it takes for the cascade to be fully reflected in laboratory values ( Michael ? ).

 

Moreover my CRP was only slightly elevated at 1.1 ( baseline under 1 and has been as low as <0.2 on one occasion but varies ). A month after fast we expect a decline in CRP, but I would expect there could be an inflammatory hit with re-feeding temporarily if LFTs typically transiently rise following breaking a fast.

 

Whereas my fasting BG is usually in the 80s, it was only 72 which is the second lowest recorded by a genuine blood draw ( as opposed to via my glucometer).

 

Also surprising, though my ketones did moderately rise on this 4-5 day fast ( remember, I did a complete water fast not FMD - I broke the fast with and FMD kit ), lipid panel was not elevated relative to my baseline. I was expecting it to be elevated based on a lecture by Dr. Klapper that Cloud kindly posted for us above, who advised not to check labs for 1-2 months following a fast since the lipid panel will be elevated by lipolysis induced by the fast.

 

Also interesting IGF-1 was up rather than down at 132 compared to last previous check about 5-6 weeks earlier at 124 ( I'm 42, how am I doing? IGF-BF3 was 3.7 after the fast, and was not obtained at the baseline) but I don't find this very surprising given test variability and moreover a true baseline would be right before the fast and who knows what it was then. My diet, though pescatarian, is very close to vegetarian by % calories. Been reducing animal protein & dietary while foods BCAA a bit further since.

 

I think the above provides some reassurance regarding inflammatory hit provided 8 hours is sufficient for markers of inflammation to be reflected on the post-fast blood draw. As for long term biomarker changes I would not expect too much of a change for me since my BMI while very high for me is only around 18 and moreover my baseline biomarkers are low and as Dr Longo's own original work has shown the group that statisticaly significant improvement was those with higher / worse biomarker ( e.g. Baseline CRP > 1). HgBA1c was lower at 5.6 rather than 5.3 but could have also been partially due to dietary and lifestyle change such as my adoption of a much narrower eating window, along with lifestyle change since HgBA1c does after all reflect 2-4 month BG average and is affected by RBC turnover,etc.

 

I would not be surprised if we see regression to the mean for my HgBA1c since that is the lowest it has been - also, who knows how long a beneficial drop lasts so unless you are fasting regularly such as with Dr Longo's intervention group - and in my case if I decide to continue I would only do this 1-2x annually at most - a better bet would be focusing on the regular lifestyle routine as the highest yield area.

 

The main hypothetical and indeterminate potential benefit of a 1-2x a year prolonged fast for someone like me is if it had incremental autophagy benefits above and beyond the autophagy I have via daily intermittent fasting ( now at 20/4 or less with one meal daily) in the context of my low-ish BMI.

 

Whether or not this is the case, and if so how much is an open question that I believe remains unanswered..

Edited by Mechanism

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Mechanism, I've been somewhat confused by many seemingly contradictory things regarding IGF1.  Supposedly chronic caloric restriction (especially protein restriction or at least restricting certain amino acids such as methionine) lowers IGF1 which lowers cancer risk and provides anti-aging benefits.  But fasting has been shown to dramatically boost growth hormone which boosts IGF1 which reduces risk of degenerative diseases and provides anti-aging benefits...

 

I've seen studies that show elevated IGF1 in seniors, a time when you'd expect declining growth is appropriate, correlates to lower mortality and improved health.  And studies that show low IGF1 in younger people correlates to lowered mortality and longer healthspan.

 

My purely speculative take on the conflicting things I've read regarding IGF1 (and many other conflicted elements of nutrition) is variability is good.   Low and high IGF1 each have pros and cons and it is probably better to go through periods of each rather than to be chronically in one state or the other.

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Hi Todd, Longo's work & others' nicely demonstrated the drop in IGF with prolonged fasts. From my reads, the shorter the fast the greater the potential boost in GH, which though a mediator of IGF-1 is not the only influence on IGF-1. For the prolonged fast lower activation of nutrient pathways ( esp with a drop certain amino acids) dominates - no citation off the top of my head.

 

The older one gets the greater role for protein and growth hormone pathway anabolic benefits to protect from sarcopenia and other wasting / osteoporosis, possibly cognition, etc. IGF-1 naturally goes down as we age anyway so a "relative" preservation of IGF-1 absolute levels of IGF-1 is not the same for this age group. So moderation in al things, with requirements / optimization shifting over time.

Edited by Mechanism

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