Why 16 Hours Isn't Enough for True Fasting Benefits, with Dr. Chris Rhodes

There's a lot of information that apply to deeper states of fasting that actually don't apply to the earlier states of fasting. But we have it in our brain that if I do a 16 hour fast, then I'm going to get an immune cell stem cell reset, I'm going to get this really deep state autophagy or I'm going to get into ketosis and that's actually not going to happen with these shorter fasts.

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Hello and welcome to the Feel Freaking Amazing podcast. I'm Wendy Trubo. Obviously, Ed is not here today. We are solo recording and we have a great guest. We're talking to Chris Rhodes. Dr. Chris Rhodes is a nutritional biochemist. He has practical experience in nutrition, biohacking, healthfully aging and fasting. He dedicated eight years of research to unraveling the mysteries behind intermittent fasting and his incredible ability to optimize health and extend lifespan. So, Dr. Rhodes, welcome. I'm so excited to talk about this because honestly, I have been intermittent fasting since before it had a name.

Amazing. Yeah, thanks so much for having me, Wendy. I'm super excited to be here.

Yeah. How do you recommend. So some of our listeners, they've been fasting for years and then some of our listeners say, I really can't go more than three hours or I get hypoglycemic. What's the message that you give for people who have a hard time going more than eight hours overnight between fasts? What do you recommend they do?

Yeah, that's a great question. I would say that, I mean, I have even more bad news than what we're already going to talk about. But if you can't go more than eight hours and over overnight, fast is what you would typically call that. Then it's, it's really hard to. You just gotta like start where you can. If you really want to get into the lifestyle, you gotta kind of be like, okay, cool, I can go eight hours. Well, tomorrow I'm gonna go nine hours and just kind of, you know, build up to that. Then 10 hours, then 11, then 12. You know, just like keep going as much as you can because that will help to Actually reset your circadian rhythm. So our circadian rhythms are very tied to our hunger responses. So just like your body knows, oh, it's X o' clock at night, I'm supposed to be winding down, getting ready for bed, starting to start my sleep responses. It does the same thing with your hunger cues and your hunger responses. So if you're constantly eating at a certain time every day, your body starts to then anticipate that food coming in at that time, and it'll make you hungry.

So muscle memory, your stomach has a muscle memory, basically, is what you're saying?

Yeah. So the thing about this is that even when we talk about standard intermittent fasting, which is kind of like this 16, 8 program, that is biochemically speaking, actually not really sufficient to truly enter into a fasting state. So we have what's called glycogen stores in our body, which basically are stored carbohydrates within our cells and our muscles. And before around 20 to 24 hours, our body is going to utilize primarily those glycogen stores for the energy that we need. So we're going to still be in more of a carbohydrate burning state for those first 20 to 24 hours of fasting. And only after that, once we've depleted those stores, do we then really start to enter into this deeper state of fasting where you get this metabolic switch from the carbohydrates to the fat metabolism and the ketone bodies. So you get into ketosis, you start more of these cellular recycling processes like autophagy, these cellular regeneration processes that are more associated with all those beneficial survival slash longevity mechanisms that happen with fasting. So by and large, this is the bad news. A lot of us are not getting as much fasting benefit as we actually think we are, because it really takes around that 20 to 24 hour mark to even get into the fasted state, let alone, you know, achieve these deeper state benefits.

A lot to unpack, Chris. So if you're someone who tends towards a ketogenic diet, do you get into that fat burning state faster or does it not seem to matter whether you're kind of keto, keto light or regular eating program, or even Mediterranean, like, where is there some on the spectrum, Is there some point where this gets you there faster or not?

Yeah, if you're eating like purely keto, like not keto light, not dirty keto, you know, truly keto, where you're not getting really any carbohydrates at all, that will definitely help you switch into, you Know that ketogenic state a lot faster. It's all really going to depend like you're talking about, on how much glycogen is in your body when you start fasting. If you're, you know, your stores are totally full, going to take longer than if they're half full or if they're a quarter full or whatever it is. And so that's going to really come down to something like, you know, how much carbohydrates in your diet, what was their diet yesterday, was it ketogenic? You know, all, all that fun stuff. So that's really going to be the switch to the ketone bodies themselves. So you can get faster there by using a ketogenic diet. However, from a, from some of the other molecular cellular things that are happening in fasting, that'll still come down to really, all right, how quickly can you work through the energy that you've taken into your body from your last meal and then kind of enter into the fasting state after that?

I mean, here's the challenge. You eventually need to eat. So are we saying, are you saying that this is, how often do you need to do this sort of longer fast?

So when we look at the animal research for alternate fasting, that's really where we see the best longevity effects and lifespan extension effects of fasting as a lifestyle, as an intervention. So that's going to look like one day of normal eating followed by one day of fasting, which is just going to be water or non caloric beverages, something like that. Then another day of normal eating, another day of fasting, and then you just rinse and repeat for an organism's entire life. When we do that, we can see around a 30 to 50% lifespan extension even without altering the amount of calories that we're consuming. So those are these really interesting unique effects of fasting itself that make it a little bit different from the lifespan extension that you can get from caloric restriction and energy restriction. That's really where we see the best lifespan extension is in that alternate day fasting regimen, which equates to, to around a 36 hour fast repeated over and over.

Do you do that yourself?

I did, I did for a while. So while I was at Stanford and getting into the whole fasting regimen, fasting lifestyle, I was really, really fascinated by it. So I just kind of started to put it to the test. So I started doing some fasting, taking my own blood, looking at my cells, seeing how their functionality changed around and what I found there. After doing a 60 hour fast where I was also taking my blood every couple hours to see what was going on. I found that that period between 36 to 48 hours of fasting was really where you get this plateau of functional benefits to cellular health. So I saw that at that 36 hour mark, my cells became more anti inflammatory, they became more antioxidant, they were more cardio protective, they had better metabolic, metabolic functionality, they had better protective ability. So it was really, really fascinating, especially as, you know, a young kid out of college, I was probably 23 at the time, just to be able to say, oh, I'm already this young healthy person, I can do this one day intervention and all of a sudden become like a super person. I thought that was so cool. So I got very, very hooked into that and did alternate day fasting as just my lifestyle for around two years while I was in that fellowship program. And that's really, really difficult because there's this big element not only of the you're not eating for 36 hours, but also just the social isolation that can come along with that. Right. You're not having meals with co workers, you're not having dinner with friends and family, or if you are having dinner with friends, you have to be the weird guy who's just sitting across from them at the table. Like, I'm just going to hold my glass of water and watch you while you eat. And like nobody wants that. Right?

Right. I was just thinking if I were to do that, I would literally have to enroll my entire world and we would have to say we eat on odd days, we fast on even days or whatever, reverse it if we want, but that we would, we would all have to do it together so that we could plan eating and so feast and famine, we could plan it together.

Yeah, absolutely.

It seems like it would be challenging. Like I've done a five day fast before and the most fascinating thing I learned was that I never got hungrier than feeling really hungry. I got really hungry. But then it wasn't like it got worse, it just, that's how hungry I got. And then it passed and then it came back. So that was very freeing to me. I thought I would always just keep getting hungrier. Do you know what I mean? Like hungrier and hungrier.

Yeah. And that was my experience as well. It's kind of that circadian reset that we were talking about where, you know, your body does have these like hunger comes in waves. Right. It's gonna be like, oh, hey, like we're supposed to be eating now. I'M gonna make you hungry as an anticipatory thing or like, you know, to let you know that we should be finding food. But if you just, you know, let that pass for it's usually around like a half an hour. Right. Then you're fine again.

Yeah, it was fascinating. So it seems like it would be difficult for most people to do the every other day eat, don't eat, definitely. So what's the next level of hey, this will make a difference. It's here's optimal and then here's. This is going to be really helpful. And then here's the minimum viable product is there, is that, do you have it stratified like that? Do you have it stratified the way I think?

Yeah, actually we kind of do. So I would say, you know, alternate day fasting, that's where we have the best data to show this. Lifespan extension, longevity effects. The next below that would probably be like a one meal a day schedule. So that would be more or less like a 24 hour fast every day. Right. And you're really condensing your eating window. So you're minimizing these negative effects of the postparandial response or like the post.

Eating response question does it matter what you eat in that time? Because that's almost intrinsically a calorie restricted approach. Unless you're eating cheesecake for your meal and eating a whole cheesecake. So does the. I'm hoping that the quality of the calories matters, but does it matter or is it simply the restriction that matters?

It's a little bit of both. So definitely, anytime you're putting food in your body, the quality of that food, the nutrients that are coming in, the micronutrients and the macronutrients, the polyphenols, the flavanols, the bioactives that are going to come in from whatever your food source is, all of that's going to impact your biochemistry in some way or another. There's really no two ways about that. That's always going to be an important factor for any element of nutrition. But the restriction itself, the time condensed eating, does also have this impact on how your biochemistry operates. Right? So your body is going to end up putting a lot of energy into that very narrow eating window of like, okay, digest, metabolize, absorb, whatever, like you know, you can't fit it all in at once. So there is going to be a restriction element that just naturally happens. Unless you're like you said, really planning it out to be like, I know what my macros are supposed to be. And I'm going to hit that mark, whatever it is, and I'm going to make meals that, you know, align within that. If you're just doing it naturally and like not putting all as much of that effort into it, then you're definitely going to restrict some calories just by way of my stomach. Can't hold it all. And then, you know, the actual, the actual postprandial response, the post eating response lasts for about, you know, four to six hours after you finish a meal. And then after that point, you'll be in more or less this, you know, restorative homeostasis maintenance state of the body. And then that's where you kind of see more of this, these fasting, like, benefits that start to show up. So that's really where you're gonna. This is gonna be really different than normal. You know, three meals a day, plus snacks, where we're kind of always in that postprandial fed state because we're never allowing our body enough time to resolve it. And that's where you can get into problems with kind of like, you know, chronic inflammation and chronic, you know, lipid and glucose swings.

Okay, what do you tell people who work out a lot? Because if you're a distance runner or if you're a weightlifter, it seems like these two philosophies don't really go together. Although I see the value. I remember I go to this trainer on weekends whom I call Evil Chris, not related to Chris Rhodes. So my Evil Chris Trainor, I went, worked out with him. God, this is already two years ago. And I didn't eat before I went because I was fasting. I'm not going to break my fast. And I'm in the workout and I'm like, I think I'm gonna puke. I have nothing in my stomach. I'm like, I'm gonna puke. And he goes, did you eat? I said, no, I didn't eat.

I fast.

And he goes, well, you can't go and do a hard workout unless you eat. And I was like, well, that kind of makes sense to me. But I wasn't in ketosis and I wasn't, you know, it was like, neither here nor there. So I'm curious what you do for people who really want to work out well but also recognize they wanna fast. Where does the happy medium or the line happen there?

Yeah. So I would say that it's really different strokes for different folks. It's going to be something different for everybody. For me, for example, I do the One meal a day schedule. That's kind of like my lifestyle right now.

Wait, which meal? I'm sorry to keep interrupting you, but I'm like really curious about which meal do you do?

Yeah, I do dinner. So that's kind of my day. I wake up, I get some green tea, I take my mimeo, my fasting memetic, right to give me these longer term fasting benefits in a shorter fasting window that'll have some appetite suppression effects that carry me through throughout the day. And then I'll usually work out in a fasted state once I'm done with work and then go immediately into my big meal of the day. And I like that because that kind of gives me the best of both worlds. Yes, I have to work out in a fasted state, but my body's kind of adapted to that at this point. And then going right into a big meal after that, then you're really promoting like all right, we're getting a bunch of protein in there, we're setting off like pro growth pathways like MTOR and IGF1 and all that fun stuff that's really conducive to muscle growth. But then we're not over indexing on it because we're going to be fasting for the rest of the time. So it's basically like really dialing in your nutritional timing to make sure that you're still supporting your muscles recovery and growth abilities.

What are you doing for your workouts typically?

So that for me is going to almost exclusively be strength training. So I will, I'll go in and do like resistance bands and you know, squats and deadlifts and like you know, basic, the basic stuff really with, with free weights, switch it up, K, do cables, pull ups, anything like that. But it's going to be a majority just strength training because that's when I look at the literature really what ends up kind of mattering most in terms of longevity. Because number one, when you focus on strength training, you're building up both muscle mass and bone density. Those are two of the best biomarkers of aging after age 65 where you really see this bifurcation. And people who can enter into 65 with really good muscle mass and really good bone density have much better prospects for longevity because there's less falls, there's less frailty that can happen. And then number two, when you build up muscle, you're also building up your metabolic rate that helps to prevent these other negative effects of caloric restriction that can happen of like decreased metabolism over time because Your cells start becoming much more metabolically efficient.

So was there something beneath that that would be the next level?

Yeah, so I would say the typical minimum viable product for fasting is going to be more of that 16, 8 style. But this is where you see a lot of controversy in the field about whether or not, you know, fasting has distinct effects, whether or not fasting is different than caloric restriction or not. Because again, from a biochemical perspective, since it's less than that 20, 24 hour mark where you deplete your glycogen stores, there's not too much of a biochemical metabolic difference of what's happening in your body versus just a more traditional eating state. So what you're going to see with the 168 is that you're going to get good stabilization of some metabolic markers like glucose levels, insulin levels, triglyceride level, you know, cholesterol levels. But outside of that, that kind of, you know, metabolic regulation at a systemic level, you're not going to get a ton of very distinct cellular effects that happen. So one thing that the fasting space is kind of notorious for is because there are so many different types of fasting and because there are so many different studies that have looked at different, you know, levels of fasting, different time frames of fasting, different patterns of fasting over different time courses. You know, there's a lot of information that apply to deeper states of fasting that actually don't apply to the earlier states of fasting, but we have it in our brain that they're actually all the same thing. So it's like if I do a 16 hour fast, then I'm going to get an immune cell, stem cell reset. Right. I'm going to get this really deep state autophagy or I'm going to get into ketosis. And that's actually not going to happen with these shorter fasts. That's going to be really the long term ones, like, you know, 36, 48, 72 hours, things like that.

Okay, and is there any benefit to doing a fast once a week for 24 hours or is it like everything better than nothing?

Right? Yeah, I would, I would say actually that like a once a Once a week, 24 Hour Fast is probably ultimately better for you from just like a cellular reset perspective than daily 16,8 fasting? Just because you'll never experience the cellular effects of the 24 hour mark in a shorter fasting window. And that applies for any stage of fasting. Right. You're never going to be able to get the biochemical effects that happen from a 36 hour or 48 hour or 72 hour, even if you kind of like, you know, stack all the, all the other hours together, if that makes sense. So yeah, going as far as you can at one time in a fast is going to be the most, most impactful and change your metabolic functioning and your biochemistry around the most, rather than just doing a lot of shorter term fasts.

So let's talk about fasting mimetics. What are you talking about when you're talking about fasting mimetics and then what falls in the category?

Right, So a fasting mimetic is just something that can recreate the either cellular metabolic biochemical effects of fasting. And that is usually something that is like a drug class of molecules. So something like rapamycin for example, is going to be inhibiting mtor, which is something that also happens during fasting and then that has specific effects on health and longevity. Or Metformin for example, was an AMP kinase activator, which is also highly elevated during a fast. So that's kind of the chemical class of what we would call a fasting or a caloric restriction mimetic. I mentioned mimeo before. Mimeo is the fasting mimetic that I developed from the research that I was doing in graduate school. So basically what we did for that was we had people come in fast for 36 hours and then looked at their before and after. And what we saw was that when people fast for 36 hours, there's this unique set of molecules that are produced by the body that are really only elevated during a fast. And we found that those were the ones responsible for activating a lot of these cellular health and longevity benefits of fasting. So we basically just took those molecules, put them into a daily pill so that you can recreate fasting at the molecular level, get those same benefits of a 36 hour fast, but without actually having to go that deep into fasting. And so that's usually what I'll end up recommending to people who are doing the 16, eight where it's like, okay, great, like you're doing this, it fits into your lifestyle. Let me give you some of these deeper state benefits that you wouldn't ordinarily experience in your shorter term fast and also help to make the fasting easier. Because the molecules that we identified have some interesting impacts on both mood, cognition and then appetite suppression as well as.

What are these substances.

So these are natural metabolites that are produced by the body during a 36 hour fast. So that's nicotinamide spermidine, palmitoyl ethanolamide and oleoyolethanolamide.

Seriously? That is quite a mouthful.

Yeah, it is quite the mouthful, yeah. When you get into the deeper biochemical terms, everything becomes very long and confusing.

Okay, so if you, I mean, nad's so unstable in pill form, are OEA and PEA also unstable or are they stable? Like, how does this work?

Right, so we're actually not using NAD itself, we're using nicotinamide, which is an NAD precursor. So that is actually very, very stable in pill form. When you take it, your body takes it up, turns it into first nicotinamide riboside, then into nicotinamide mononucleotide and then into nad. So nicotinamide in and of itself is kind of like a broad spectrum NAD precursor that's going to be giving you all of these benefits of both nicosinamide riboside, NMN and nad. Palmitoyl ethanolamide and oleoyl ethanolamide are also very, very stable because they're lipid amides, so they're not prone to peroxidation like normal lipids are. They just have a different chemical structure which makes them very shelf stable. And the cool thing about our formulation is that we've done three clinical studies with it so far showing that we can, number one, all the molecules are bioavailable, that you take them up, they come into circulation after around an hour and stay elevated for four to six hours after. After that they can also recreate these cellular fasting benefits even during a meal. So those same anti inflammatory, antioxidant, cardioprotective, metabolic enhancement effects. We've also shown that with eight weeks of supplementation with this formulation, we can get a two and a half year reduction in biological age. And also shown that in eight weeks of supplementation we can have these really powerful impacts on appetite suppression, hunger control, improved satiety as well, powerful impacts on appetite suppression, hunger control, improved satiety, as well as metabolic marker optimization. So really improving fasting glucose levels, cholesterol levels, as well as reducing cellular stress levels. So everything that fasting should be doing for you, but just, you know, a lot simpler.

So is it, is it something that you would take at the beginning of your fast or the end of your meal, or would you take it at the end of your fast? So if you're doing a 16, if you're doing a 24, when are you taking it? If you're doing a 16, eight, when do you take it?

Right, so that's really all dependent on whatever feels best for you. I typically say that the best time to take it is when you're kind of like feeling the hunger the most. Right. Like when that hunger pang comes in. That's kind of the right time to take mimeo to help carry you through or if you're doing something where it's. Or what we were talking about before, right? Where it's like, I really want to increase the amount of time that I can fast, so let me go as long as I can without any help and then, you know, take the mimeo and see how far I can go again after that.

Well, wait, wait, I'm sorry. Does it take about an hour to kick in so that you feel it?

Yeah, that's correct, about an hour.

So if you say, okay, normally I can get to 9am and then I absolutely lose my mind, then it would be, okay, take it at 8 o' clock so that you can get. It'll already kick in by nine o' clock when you're already typically gonna lose your mind. So plan ahead. Is that how you would do it?

Yeah, that's how I would do it. But the nice thing about Mimeo is that in all the three clinical studies that we've done, nobody was actually fasting during those studies. So everybody was just having a normal diet and lifestyle. No changes need to happen. So that's why we call it a fasting memetic instead of like a fasting enhancer. Although it can be a fasting enhancer and that's how I use it. So I'll take it, like I said, in the morning with my green tea and just kind of use it as a way to help carry me through the day.

Does it have caffeine in it?

No, it does not.

And what about people who are getting hypoglycemic and that's why they have to stop fasting earlier than a 16 hour. Can this help level them out?

It would definitely. Like for hypoglycemic, that might be a little bit trickier because these molecules we've identified can help to, you know, lower glucose levels and help control them and maintain them in that homeostatic range. But we don't know if it would help to upswing a hypoglycemic response.

Okay, okay. Any downsides to doing this?

So the only downside to doing it is some people do have a genetic sensitivity to niacin metabolism. So nicotinamide is a niacin derivative. So if you are sensitive to that, there can be some gi Upset that happens typically that can just be resolved by taking the formulation with food and especially, you know, yogurt, because that has both protein and lipid matrices that can help bind the nicotinamide and smooth out its digestion. But that niacin derivative. So if you are sensitive to that, there can be some, you know, some gi. Upset that happens, typically that can just be resolved by taking the about. I would say, you know, 5% of people actually have that sensitivity. And otherwise, for anyone else, especially, you know, if you're already comfortable taking supplements on an empty stomach, not really much downside because all of these molecules are unnaturally produced by the body anyway. So our body inherently knows how to absorb them, utilize them, metabolize them. So it's a very safe product. Very minimal side effects.

Is it once a day? How many pills and how many times a day?

Yeah, just two capsules. Once per day.

Okay, we'll put this in the show notes. But where can people find out more about you?

Yeah, so if they want to find out more about me, specifically, they can watch me scream about nutrition into my bathroom mirror on TikTok. I'm at formulation with food and especially, you know, yogurt, because that has both protein and lipid matrices that can help bind the nicotinamide and smooth out its digestion. But that's about, I would say, you know, 5% of people actually have that sensitivity. And otherwise, for anyone else, especially, you know, if you're already comfortable taking supplements on an empty stomach, not really much downside because all of these molecules are natural at that nutrition doctor. That nutrition doctor. They want to find out more about Millie. Produced by the body anyway. So our body inherently knows how to absorb them, utilize them, metabolize them. So it's very, like, very safe product, very minimal side effects.

Is it once a day? How many pills and how many times a day?

Mimeo. They can go to mimeohealth.com that's M I M I O health dot com.

Okay, beautiful. All right, Chris, thanks for being on the show. This is really cool. And thanks for letting me, like, really hammer you with questions.

Oh, no, I love it. I'll talk about fasting till the cows come home.

No, it was great. So for the listeners, I hope this made it.

Yeah, just two capsules, once per day.

Okay, we'll put this in the show notes the difference for you and go look Dr. Chris Rhodes up and follow him and buy the MIMU. And do what? Do what you need to do to get healthy so you can feel freaking amazing. And Chris thank you so much for joining us for this episode of the Feel Freaking Amazing podcast.

Absolutely. Thanks for having me. Awesome.

My pleasure. But where can people find out more about you?

Yeah. So if they want to find out more about me, specifically, they can watch me scream about nutrition into my bathroom mirror on TikTok. I'm nutrition doctor that nutrition doctor they want to find out more about.

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Mimeo. They can go to mimeohealth.com that's M I M I O health dot com.

Okay. Beautiful. All right, Chris, thanks for being on the show. This is really cool. And thanks for letting me, like, really hammer you with questions.

Oh, no, I love it. I'll talk about fasting until the cows come home.

No, it was great. So for the listeners, I hope this made a difference for you. And go look Dr. Chris Rhodes up and follow him and buy the mimeu and do what you need to do to get healthy so you can feel freaking amazing. And, Chris, thank you so much for joining us for this episode of the Feel Freaking Amazing podcast.

Absolutely. Thanks for having me.

Awesome. My pleasure. Don't go it alone.

It's not a social journey until others join.

Share this with your friends.