CR Curious

I'm willing to believe that Attia's concern is misplaced, but my understanding is that the relationship between muscle mass and strength is pretty robust and I wonder if the threads Sibiriak referenced (which I looked for and found interesting/insightful) cite enough evidence that we would tend to doubt that maintaining muscle mass in old age will tend to lead to less falls, hip fractures, etc. and that muscle mass earlier in life gives you more of a "cushion" later in life as you start to lose muscle mass as you age (which is inevitable, of course). That said, another datapoint here is the stuff about rapamycin. Rapa seems to help maintain muscle mass in old age based on the (albeit limited) evidence I've seen. But the interpretation of the rapa studies I've seen is that it's good, somehow, to suppress mTOR and then turn it on--which would imply that high (animal) protein would be good for health sometimes (when you want to turn mTOR on). Right?

I wonder if folks around here have given a lot of thought to how to optimize sleep? I mostly just do the normal "sleep hygiene" stuff and try to finish eating dinner as early as I can get away with so that my resting heart rate and heart rate variability get as close to baseline as possible (i.e., eating increases heart rate and lowers HRV, which I think is bad for sleep all else equal, so I want to try to get back to low heart rate and high HRV). I don't have regular access to a sauna, but I think that is something that might improve sleep quality if timed correctly. I have found any supplements that seem to increase sleep quality for me, though I've experimented a fair amount. Anyone thought about this?

Thanks for the pointer, Sibiriak. I searched and found at least one thread where you discussed this. Seems convincing that the high (animal) protein/muscle building diet does not make sense! I wish more forum users had weighed in, though. I wonder what the Attia crowd would say in response? Some examples of Attia's arguments: https://peterattiamd.com/dispelling-myths-protein-increases-cancer-risk/ https://peterattiamd.com/are-you-eating-enough-protein/ https://peterattiamd.com/category/nutritional-biochemistry/protein/ I'm particularly interested in whether anyone has arguments responding to the top clip with Layne Norton (there are notes below the video if you don't want to watch it). It has a provocative title--"Dispelling myths that excess protein intake increases cancer risk"! One argument in there is that there may be a difference between an acute and chronic rise in mTOR/IGF-1. I've seen other folks like, e.g., Kaeberlein who does all the research on rapamycin argue that cyclical mTOR activation might be optimal. And that might suggest that, e.g., doing TRE with animal protein could be good--keep mTOR low generally but really go for it when you activate! So maybe OMAD with a fair bit of animal protein (which is what I've generally been doing, though not really for longevity reasons) is one way to approach it. There's a book called The Switch that also takes the view that we should cycle between anabolism and catabolism. Another thing Layne Norton points out is the meta-analysis that showed no ill effects on people who ate a lot of meat but also ate a lot of fruits/veggies. FWIW, Rhonda Patrick has discussed this issue a fair amount, too: https://www.foundmyfitness.com/episodes/brad-schoenfeld https://www.foundmyfitness.com/episodes/stuart-phillips https://www.foundmyfitness.com/episodes/how-much-protein-should-you-eat-muscle-growth-vs-igf-1-longevity-concerns-rhonda-patrick The top 2 clips are just interviews, so I wouldn't say that RP has staked out a position on this issue but I think it's something she's thinking about. Thanks to all who have responded thus far! I'm deeply grateful that you are sharing your knowledge!

Hi everyone, I'm new to the forums and very impressed with the level of engagement and sophistication. I wasn't expecting to be convinced that we don't have good evidence that CR works in humans on a CR forum, but I was. That said, my read of some of the forum posts (and other evidence) is that: People tend to think that the evidence suggests fasting is probably good. That means shrinking your eating window down essentially as much as possible and possibly doing some extended (e.g., 5-day fasts). Though Longo continues to insist that 12 hours of fasting and 12 hours of feeding is good. He seems to be an outlier. David Sinclair is into OMAD and seems to think that fasting is the key but I think I've seen some stuff suggesting that he buys into CR but thinks it's too hard. People tend to be bullish on protein restriction as a strategy for slowing aging. So eating vegan, keeping protein around 10% of diet. Longo/Fontana stuff. But some folks on the board seem to be vegan for ethical reasons. That's great, but I do worry that there may be motivated reasoning when it comes to the health effects of animal protein. Both of these things would tend to support the mechanistic stuff about mTor/IGF-1/etc. This is the very basic growth/longevity tradeoff model. Protein turns on pro-growth signaling but that's bad for longevity. Fasting/eating less protein promotes autophagy. Hormesis. Etc. Now, I'd welcome feedback suggesting that, like Dean's post on CR in humans, the evidence for these propositions is weaker than some make it out to be. Of course, nothing is clear cut but the question is whether the totality of the evidence is strong enough that it's worth acting on. I used to think that was true of CR (though whether I had the willpower to actually do it was another question), but now I think the evidence is basically 50-50 on whether it'll work in humans relative to a diet that doesn't make you fat. So I'm not really going to put in extra effort to do CR. But my impression is that, though the evidence is not slam dunk by any means on fasting/protein restriction, there's enough that it's worth doing. Here's my issue, though. There's the Peter Attia view that we should prioritize preserving muscle mass for healthspan. (This seems to be what he currently thinks; Attia has changed his views a lot.) And indeed, there's good evidence that muscle mass is important for longevity/healtspan. And there are a lot of exercise researchers (Stuart Phillips, Layne Norton) who think eating high protein is important for longevity. Rhonda Patrick has had some of these kinds of people on her podcast recently. These kinds of folks talk a lot about frailty/sarcopenia. Now, I know that Longo says increase protein after 65 for this reason. But Attia makes the point that we know muscle declines with age, so we want to be starting from as high of a baseline as possible. Which would imply building muscle early in life is optimal. The problem is that the muscle-building diet seems to be the exact opposite of the OMAD/protein restricted diet. There seems to be good evidence that ingesting protein leads to a transient increase in muscle protein synthesis, so the way optimal to build muscle is to eat protein (especially animal protein because it has lots of leucine!) at regularly spaced intervals (and do strength training, of course). And of course, that makes sense if the basic growth-longevity tradeoff model is right. Have others thought about this? I expect that there is some unavoidable tradeoff here, as the growth-longevity model would imply. But does that mean that a shorter eating window isn't necessarily better? How much muscle mass is enough to avoid age-related issues? Might higher protein make more sense after strength training? One thought is that regular strength training will be enough so we shouldn't worry about muscle building on the diet side. But I'm not sure. I'm 30/yo, male. I do OMAD for the longevity benefits and exercise a fair amount. I also strength train 3 times/week primarily for longevity. (I run a lot, too, more than I would if I were just concerned about longevity.) I eat a pretty high protein diet with lots of animal protein but am thinking about trying to reduce. My approach has pretty much been trying to split the difference by eating high protein for one meal, usually timed so that I eat as soon after strength training as possible. (I find that protein is good for satiety, so high protein diets may be better (at least for some) in reducing body mass.) But I am curious if/how others have tried to split the difference here.

It would be amazing if Bryan would do an AMA or something. I think what he's doing is really awesome and it's especially great that he's willing to talk publicly given the amount of vitriol he gets for doing something that could benefit everyone. In the things I've read or listened to, I have agreed with pretty much everything he says. I hope he is planning to become more of a public presence in nutrition discussions (though probably not--he has better things to do!). I would love to see him have a conversation with Attia, Rhonda Patrick, Huberman, etc. And especially with some of the bodybuilder types who seem especially skeptical of calorie/protein restriction like Layne Norton. Kernel seems great, too. I've been wondering about his routines since I read the Bloomberg story on Blueprint. Some questions I'm curious about (especially if he's reading this!): Most basically, I would like to know Bryan's take on CR in humans. Obviously, he seems to be bought in, but (of course) there is a lot of controversy on whether it will even work in humans. How was he convinced that CR will have benefits? Is it all about biomarkers he is tracking? If so, which biomarkers? Bryan's view appears to be that the lowest bodyfat % possible is best, at least until ~6%. Is that true? Relatedly, there is the Peter Attia approach, which is to eat a lot of protein and maximize muscle mass to avoid frailty. Does he have a response to that? I know he does not look frail right now, but the Attia argument is that we all predictably lose muscle as we age so we need to put on as much muscle as possible early in life. Of course, both of these questions touch on the growth-longevity tradeoff--including whether there is any such tradeoff, etc. I view this as raising several related questions, many of which may ultimately implicate the mechanistic stuff on mTor/AMPK/IGF-1. One of these is about protein restriction. Does Bryan have a view on optimal % of protein? And why vegan? Another is fasting. Bryan seems to think fasting is generally good. Is this just about CR, or does he think there are additional benefits? What is Bryan's view on extended fasting? Many people seem to think that ~5 day fasts for autophagy confer outsize benefits. Related to both of the previous two, it seems that ingesting 20-30g of protein leads to a transient increase in muscle protein synthesis. So if you want to build muscle, you pretty much want to do the opposite of fasting--eat at regularly spaced intervals to ensure that MPS remains elevated. Would be interested if that factors in. I am very interested in Bryan's work on optimizing sleep. I have read that he (at least used to) finish eating before 11 am so that his RHR and HRV would return to baseline before bed. I'm intrigued by that but not willing to forego dinner with my significant other. And given that substantial daily fasting seems good, I end up eating a lot of food in the evening. But I worry that this is leading to suboptimal sleep. In his experiments, what was the latest Bryan could eat such that RHR and HRV went back down to baseline? I imagine the relationship here depends both on when and how much you eat. So you can eat a little bit even right before bed and be fine. But if you are eating a huge meal (not uncommon for me to put down 3000 cal for dinner in whole foods, mostly lean protein and non-starchy vegetables, no sweat), it might take several hours. So it's a function both of timing and size. Which leads to a further question: Should I eat more calories earlier in the day? Let's say I finish eating dinner at 7:30 and go to bed at 10:30 pm. Should I be looking to eat as lightly as possible there? So maybe (to the extent possible) I should have a relatively large meal at, e.g., 3:30 pm? I am also curious on the evidence that RHR and HRV are good proxies for sleep quality. I imagine they are, but I'd like to dig in to the evidence on that myself. This is more specific to me than the other questions but I think the sleep stuff is super interesting and important! In general, I wish Bryan would give more explanation of why he makes the various choices he does in Blueprint. It's admirable that he goes into such detail on the "how," but he could really help move public understanding forward if he (or his team) started writing up their approach.