Who here still fasts? Has your thinking around fasting changed?

I know it has become a bit less trendy to fast, and to also focus on building/maintaining muscle. My length and frequency of fasts have definitely reduced (once in a few months rather than once/more per month). Yet, I believe there are benefits to fasting, and I’m currently on a 3-day of a fast.

I’m curious how you folks think about fasting currently (?) To make sure I get more out of less fasting, my current fast is in combination with (5mg everolimus + 1mg rapamycin + 3 slices of grapefruit).


Isn’t taking rapamycin mimicking fasting? :sweat_smile:
I tried fasting years ago, some 15-20 years ago I was reading some Buchinger texts and was really into fasting. I did few 10 days fasts, first time was with a friend at a clinic. It was fun doing it with someone and later I did it every few months, even wanted to try a 30 day fast… My friend was later diagnosed with bulimia/anorexia and I was starting to associate fasts more and more with some sort of anxiety self medication. :face_with_open_eyes_and_hand_over_mouth: I quit my fasting and more or less all my dietary restrictions some years ago, maybe 10 (time flies). Few years ago I read Valter Longo book, and probably his FMD is something I would be willing to try. Looking back I didn’t seem to be getting any benefits from my fasts. Any weight you loose comes back really quickly and since I did not have any health problems it would be difficult to spot any immediate benefits. But I did loose a lot of muscle tissue in these years. IDK if it was fasting or just lack of proper exercising and too little protein in diet, but after that decade I ended up skinny fat… I had maybe 5kg more, but was almost 25% BF. I think fasting might be beneficial in some ways but me personally would not do it again and since taking rapamycin is basically fooling you body you are fasting what would be additional benefit?


Are you saying it is less trendy to focus on building and maintaining muscle? It sure isn’t for me, and in fact the reason I don’t fast more than once a month is because I am trying to build and maintain muscle. If you are over 50 as I am (maybe even over 40) you should absolutely focus on building and maintaining muscle. Sarcopenia will lead to frailty and falls and will reduce your lifespan and quality of life. There is at least one study that claims rapa protects against sarcopenia but there is no substitute for exercise. Building muscle after 50 is not as easy as when you’re younger but it is still possible!


I was saying, that that period when I was doing 10 days fasts was also not good for building muscle. When I was young I trained skiing and had good muscle mass, later I had an injury and had to quit. I focused more on other things in my twenties rather than building and maintaining muscles. And suddenly even when maintaining more or less same weight all the time I was loosing muscle and gaining fat. I reversed that trend some years ago, now I am same weight as when I was 18., have 11% BF and feel in great shape.
I totally agree that maintaining strength and muscle mass in the most important thing when aging. I would like to build some more muscles if possible in coming years. That is why I am not sure prolonged fasts would do me any favor now.


I meant the other way. There is more focus now on building and maintaining muscle, and rightly so. But I’m curious what that means for those who also believe in occasional fasting — i.e. how have folks updated their fasting strategies?


I still fast for two days about three times per year. I take my rapa dose with sardines on the morning of day 1. I seem to get a bit more acne after a fast plus rapamycin compared to rapamycin with my typical diet. Fasting does hurt my strength gains, but I am hoping for an autophagy benefit.

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I fast frequently, for convenience throughout the day. It’s also a good way for me to control calories without having to count anything, which I refuse to do.

I think it’s more important to get infrequent, longer fasts in than daily ones, though I always work out fasted, it makes me feel way less sluggish.

I also make sure I’m fasted for at least about 18 hours before taking rapamycin and then go another 24 hours or so. Can’t prove that it helps, but I figure anything that tends to suppress mTOR can’t hurt.


I concur: building muscle after 50 is definitely hard work, but can be done. Even without Rapamycin, supplements, or other medications. (Maybe some diet, but unclear). I’ve always been health but more of a backpacker build and never upper-body; new muscle formation is now noticeable in place I’ve never seen a muscle. Building muscle seems to have raised my natural hormone levels, and I see nice increases in my vein volume so there must be other benefits I cannot see. It’s also fun for the mid-20’s guys side-eyeing me at the gym “how the HELL is that guy with grey hair lifting that?!?!” I’d STRONGLY recommend (non-ridiculous) muscle building.

And I can also concur that I wouldn’t recommend sarcopenia as a tolerable outcome for (as Peter Attia calls it) your “terminal decade”. I watched my father go through that and it looked beyond miserable. I ain’t gonna go that way without a massive fight.

My “longevity plan” is to build muscle (not to the “Arnold” level, but so I have a nice solid covering of muscle, particularly in my trunk/abdomen/hips so movement is fluid and low-pain) even at the expense of stimulating MToR. From here, assuming I haven’t caused other damage (CVD, cancer, etc) I should be in a good position to extend healthy longevity via a variety of means, including Rapamycin. I’m using low-carb (planning for this indefinitely) because it works well for me, and have been mostly “carnivore” since January (a test that seemed to work with the gym work — I had planned one month out of every quarter to build muscle, and then the next two for longevity and repeat, but I’ve extended the first month much longer because of results and enjoyment). Alas, it’s only a theory, albeit one I’m literally betting my life on.


Regarding fasting, I’ve regular done four-day fasts every (roughly) 1.5 months for the past 2.5 years — maybe 15 of them. It’s difficult — particularly the second day — but I usually feel very good afterward. I did the first one to jumpstart my low-carb diet, but really now use it for the supposed autophagy benefits as well as weight reduction (if I’m honest — my feeling is most of my weight reductions were mainly from fasting, and low-carb only kept me from regaining the weight). My physical feeling is that this does something although I’ve never blood tested myself before/during/after so no useful data to provide you.

I also do “restricted feeding windows” most days, but have no feeling that this does anything other than prevent me from overeating or snacking (something I’m prone to do otherwise). If there’s an additional benefit, I’m unaware of any effect.

What that mean? You fast throughout the day?

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@KarlT : If this was directed at me, I (often) don’t eat during the day and only eat over a four-hour window at night. Somme people call this “fasting”, and some people call this a “feeding window”; since it’s every day and not even 24 hours I personally don’t call it “fasting” but to each her/his own. I don’t do this every day, and I feel good doing it so continue. There’s supposedly some benefits aside from calorie control but there’s not sure the research is great here and I personally can’t confirm any specific benefits (I would have guessed this is too short for autophagy, which is a benefit of longer fasting, but what do I know). I also typically work out before I’ve eaten (so ate the night before and that makes 18 hours since I last ate.

Separately, I have done “fasts” which are typically four days.

I might try a two-day (full 48-hour) fast every week for a time: this should provide autophagy benefits, but at s’more-regular basis. And skip the four-day fasts for a while. I assume there is benefit from mixing it up a bit so your body doesn’t get used to anything.


No, wasn’t directed at you. Tough to differentiate these terms as there are no great definitions.
For the purpose of autophagy, I would think “fasting” is at least 48 hrs without calories. Anything less than 24 hrs I would call “time restricted eating.”
I think there is growing evidence that there is significant cost in the form of muscle loss, to fasting.
Like you, I did time restricted eating out of convenience, but now I break that up with protein bars.

I do one long fast (72hrs+) in early January as I’m fairly certain I would have eaten far too much over processed rubbish foods over the Christmas holiday period.
I take activated charcoal over those three fasting days to mop up any toxins being released.

The dog data from @Krister_Kauppi interview with Matt Kaberlein seems to point to a OMAD fast having longevity benefits.


I practiced OMAD everyday for one year but my experience of that was that I got too skinny of that. So 1.5-2 meals per day seems to be the sweet spot for me. So today I do around 18-20 hours fasting every day. I have taken a break from my extended fasting for around 36-72 hours because I want to see how my different biomarkers develop when I’m on rapamycin. In the autumn my plan is to ramp up the extended fasting again.


I work in a restaurant where (ironically) it’s difficult to find time to have a break and eat a meal, so many days, I get off at 4 or 5, eat dinner, and that’s it. When I take my rapamycin once monthly (I’m young and so am dosing conservatively), I always take it fasted.

Do you know what happened to body fat and lean mass on OMAD?

I don’t have any objective measurements from DEXA or any other instrument but I would say both body fat and lean mass went down. It was hard to build muscle on that but when I went back to 1,5-2 meals per day and increased also protein intake then my body started to respond better to resistance training. But if I increase the meals to 3 per day my guess is that muscle building will increase even more but now I’m satisfied with the progress. I don’t need to get so much bigger than I am today.

I know also Peter Attia has quite recently started to switch his view on fasting because of the risk of decreasing lean mass. Especially if people are not resistance training. But my view is that if you resistance train than fasting around 16-20 hours can work. The biohacker Siim Land has practiced 1.5 meal per day for many years and built a good amount of muscle. But it’s important to keep in mind that Siim is still a young guy. I don’t know how well his protocol would work for an elderly person. I’m 45 years old and not near his amount of muscle but for me I think it works ok.

He calls it OMAD but it’s more 1.5 meals I would say

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“I got too skinny”
My hunger pattern is such that I could easily do OMAD and I tried it for about one week.
The problem was that it was just too uncomfortable to try to pack a full day’s calorie allotment into just one meal. I eat my first meal when I am hungry, which usually occurs between 12:30 and 3 PM. So I am with you in eating 1.5 -2 meals a day.
I do time-restricted feeding because that is my natural response to eating. I didn’t realize this until after I retired and could eat anytime I wanted to.


When do you usually eat you meals? I eat my first around 2PM and the second 6PM with the family. Research studies seem to point that it’s better to eat breakfast and lunch instead of lunch and dinner but if I do that I miss the family social interaction with the family at the dinner which I see as an important part.

Dr Brad Stanfield usually express this “Eat breakfast like a king, lunch like a prince, dinner like a pauper” which is quite good align with the above.

Here is also an interesting post from Rhonda Patrick