Debunking Metabolic Myths With Dr. Ian Smith
15 Dec 2025 · 51 min
Podcast episode (recorded Nov 8, 2023) in which JJ Virgin interviews Dr. Ian Smith about metabolic health and his Met Flex Diet. They define metabolism and metabolic flexibility, list signs of metabolic inflexibility, and explain how the Met Flex program uses graduated phases, multiple intermittent-fasting strategies (time-restricted feeding, 5:2, alternate-day with 500 kcal days), and carb-cycling to retrain the body to burn both fats and carbohydrates. Exercise (HIIT, resistance training, mixed sessions) and caloric variability are emphasized as complementary tools. Dr. Smith reports program outcomes observed in his group (people losing up to 20 lb; average ~14–16 lb in six weeks) and cites age-related metabolism points (metabolism decline typically starts ~age 60 and slows ~0.7% per year).
Questions this episode answers
November 8, 2023
People lost up to 20 pounds; average weight loss about 14–16 pounds in six weeks.
Around age 60, slowing about 0.7% per year.
Page 10 (signs include anxiety/depression, need for stimulants like coffee, difficulty losing fat, constant cravings after eating, fatigue/crankiness when fasting, post-carb-meal fatigue, fluctuating blood sugar).
Time-restricted feeding (TRF), the 5:2 method (two low-calorie days), and an alternate-day method with ~500 calories on restricted days.
Chapters
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I'm JJ Virgin, PhD dropout.
Sorry, mom turned four time New York Times bestselling author. Yes, I'm a certified Nutrition specialist, Fitness.
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Health conferences and trainings around the globe. But I'm driven by my insatiable curiosity and love of science to keep asking questions, digging for answers, and sharing the information I uncover with as many people as I can. And that's why I created the well Beyond 40 podcast to synthesize and simplify.
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In each episode, we'll talk about what's working in the world of wellness, from personalized nutrition and healing your metabolism to healthy aging and prescriptive fitness. Join me on the journey to better health so you can love how you look and feel right now and have the energy to play full out at 100.
You ever feel like you need a mechanic for your metabolism? Like things just feel stuck, they're not moving and you're just not quite sure what to do? Well, today I've got you because I'm actually going to be talking to someone about how you can become your own metabolism mechanic. I have got someone with me today and this is funny because we've literally been on a lot of the same shows in a lot of the same places and somehow in the last decade we have never met in person or never even talked on the phone. This was a super fun interview to do and I've got a new pal and I love as you're listening to this to think, would you love to watch us do some exercise videos together? Because I think we're going to line up to do that. I've got with me today, Dr. Ian Smith. Now you might know him as the number one New York Times best selling author of the book Shred as well as 15 other books including he is a fiction writer too, which is pretty cool. He was on the Rachael Ray Show. He was also host of the Doctors. He was a medical expert on Celebrity Fit Club, and he also created the national health initiative, the 50 million pound challenge, and the Makeover Mile. He's also been the medical correspondent for NBC News Network and News Channel 4 in New York. And he has been on the NBC Nightly News and the Today show and a whole bunch of other stuff. We're going to be talking today, though, about really this idea that you need to get metabolically healthy to lose fat. You don't lose weight to get healthy. And, you know, as we started to talk before we got on, I'm like, oh my gosh, we're so in line with this and how to use diets as tools. And that's what we're going to be digging into today with his new plan, the Met Flex Diet. Burn better fuel, burn more fat. Now, I've got really great show notes, too that you're going to want to pop into. We'll have everything on your podcast player of choice and also at jjvirgin.com forward/med net flex and that's M E T F L E X jjvirgin.com forward slash met flex. For the Met Flex Diet, try to say that three times fast. And one of the things you're going to find there is a link to his Facebook group. And he has a really active Facebook group going through the diet. So lots of ways to see stay connected with him. And I will be right back with my new pal, Dr. Ian Smith. Stay with me.
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Cafe Bustelo Espresso styled iced coffee is hitting refrigerators with a cold front that'll sweep through your senses. So keep the coffee pours long and the cold sip slow. Cafe Bustelo Estaki. Okay. Dr. Ian Smith. I don't know how we have never met in person or even online before now. Like, how'd this happen?
You know, I know your name, of course, and you're a great body of work. We have been friendly competitors. I put that in quotes because I think that there's so much help needed that there are not enough of us doing the work. So we're not against each other, but we've been in the same space for a long time. But I've admired your work. And I also admire. This is a little kind of aside, but I admire when people who are in a particular genre or industry or discipline actually look the part. And so I've always admired that. Not only did you talk about health and wellness and fitness, but you also practice what you preach. I admire that.
Thank you. Words are my love language. So you just, like, went off the charts there. And I think that we prove it on ourselves first. Right? I'm always my first lab rat. And I love what you talk about in this book, about being a metabolic mechanic and how we all can be a metabolic mechanic. And you look at now the crisis we have with metabolism and obesity. And first of all, going back to your thing about competitors, people don't buy one diet book, and every diet book that's written brings out new ideas that other diet books can jump from. So I never view competitors. To me, we're all collaborators.
That's right.
And I view diets as tools. And it's like, what do you need at this point in your life to get what you're looking for to learn something? It's like, there's no diet absolutes. Anyone who tries to tell you it is like, come on, that's crazy. But, like, is this the right thing for you in your life? And can you learn some things from doing this? Which I thought was very interesting as I was looking at your book, because going through that process, someone will uncover a lot about themselves and their metabolism. And that's so key important because we are gonna know we're the best people to ourselves. Right? I'd love to dive in first because I love this statement. I got it from Dr. Diana Schwarzbein 25 years ago when we were doing seminars. It's not a popular statement, by the way. She goes, people don't lose weight. To get healthy, they get healthy to lose weight. And I'm like, oh, that's tough to sell. But her whole thing was, you've got to heal your metabolism. A healthy body should be able to burn fat, build muscle, have great blood sugar, et cetera. And I feel like your book is really taking that premise. So I was super excited to see this. So let's first just unpack metabolism. Cause I feel like that word gets thrown around a lot and boosting your metabolism, speeding your metabolism, and people don't really know quite what it means. So let's unpack what a metabolism is and then really kind of the current state of our metabolisms out there.
Let me first start off by saying I have to say this to you. The reason why I have written so many books in this particular space is because there is no one program that works for everyone. And the way people present the information, one reader may be able to accept it and understand it the way I present it versus how someone else presents it, and vice versa. So I never think that there are enough books in this space because it really depends on the end user or the reader and what the information is. So it's very important in my career and what I do is to try to take ideas that I've not talked about or that I find interesting and to try to bring them to people. And so metabolism is something I've never talked about before. Well, I've talked about it, of course, but I've never really delved into it. Right. I've never focused on metabolism per se. In this particular book. I say in the opening, I came upon it by accident. So many people were saying to me, Dr. Ian, I am eating better, I am exercising, like you say, to exercise. And I still can't get that number on the scale to move what is going on? And I've heard this for many years, but I decided, what else could be happening when people do this and can't get the results? And that's when I discovered this term that I'd never heard before, metabolic flexibility. Before we get into what metabolic flexibility is, let's talk, as you have asked, about metabolism. Metabolism in a scientific way really is the collection of all the processes that are occurring in our body that keep us alive. So there are billions of chemical reactions, physiological processes that are occurring every second of our lives to keep us alive. And that is what metabolism is. It is the collection of everything that the body is going through. Another way of looking at metabolism is that metabolism is work. Okay? It is the work of the body to exist. That is our metabolism. A third way, and a more kind of layperson's way of looking at metabolism is, in my opinion, metabolism is like a fireplace. And the question is, how big is that fireplace? How much wood can you put in that fireplace to burn, then using that heat as energy to warm your room? Okay, and so that's what metabolism does. Metabolism is work that requires energy, and that energy then allows the metabolism or allows the work to be done. Now, what does that mean in practical terms? People who have what we call, in quote, slow metabolism, it's better to look at it in the fireplace analogy. People who have slow metabolisms have small fireplaces. They can't burn a lot of wood at once. They have to keep putting more wood in in order to burn it. And so it requires more wood and more time that you have to put it in there to get the heat you need for the room. Someone who has a big metabolism, has a fast metabolism, has a big fireplace. You can put a ton of wood in at once, and it all burns and it heats the room up very quickly because you're using more wood, more logs. And so people try to understand or use the word fast metabolism, slow metabolism. And so that, to me, is kind of my take on what metabolism is in the more layperson's viewpoint. It's more scientific, of course, but. But for the purposes of this discussion, that is metabolism.
There's so much talk about slow metabolisms and what happens as we age. I have a big theory about it. But of course, the research really shows that it's not till 60 plus that your metabolism does start to decline. So it reminds me, because I've been in the weight loss world for 40 plus years, and way back when, everyone was big boat. Remember that? Everyone was big bummed. I'm just big blonde. And I'm like, well, here's the test for frame size. No, you're not. And then now it's like everyone's got a slow metabolism. I do think they've got to take into account that period of hormonal chaos that women go through when they're going through perimenopause. Like, when they say that, I go, this is not a woman saying this. This is a dude. No woman can say that during that time because things go sideways. However, the reality is, as we know, that probably it's not a slow metabolism that's the problem here. Would you agree?
I agree 100%. First of all, Big Bone was around for a long time when I was doing a show called Celebrity Fit Club. What I did was we had this guy who was a rapper. His name actually was Bone Crusher, and he was about £400, 375. £400. And he insisted that he could not lose a significant amount of weight because he had big bones. And so what we did on the show was I said, hey, guys, let's do this. We X rayed his bones, took an X ray of my bones, we put them up on a light box in the studio on camera, and he had to choose whose bones were whose. And guess what? He thought my bones were his bones. So unless you're Shaquille O' Neal and 7 foot 2 and all that kind of stuff, yes, he has bigger bones, but the vast majority of us do not have big bones. So then we get to the metabolism issue for the longest, and I am guilty of it, because that's what was the mode of thinking. We always thought that at about the age of 30, your metabolism starts slowing down and then it falls off of a cliff based on age and genetics. Well, new research says, as you have stated, most people, their metabolism doesn't start slowing down till about the age of 60. And when it does slow down, it's only slowing down about 0.7% per year. Now, that doesn't take into account, as you've just stated, which is the hormonal changes that happen in women during perimenopause and during menopause. And so I believe that it's not about metabolism slowing per se for women during that age bracket or that biological age bracket. I think that really it is the hormonal storm that is occurring that affects the metabolism, and the result they see is difficulty losing weight or weight gain. So I just want to agree with you on that. I want to go one step further and say that we talk about metabolism in terms of how fast or slow it is, how it affects weight gain. But metabolic health is something that really kind of is bigger than metabolism in a way. Metabolic health is an indicator of how healthy your overall metabolism is, not from a standpoint of speed, blood pressure, blood sugar levels, triglyceride levels, waist circumference. These are things that we look at, indices that say to us, what is your metabolic health? And that is the key. We need to have a good metabolic health indicator, not necessarily always a fast or slow metabolism.
And that goes back to that. You have to get healthy to lose. I wish we could get off even saying losing weight. You have to get healthy to lose fat and hold onto or build muscle because your body isn't a bank account, it's a chemistry lab. And yes, that's time during that perimenopause menopause, when all of a sudden you're becoming insulin resistant. You are now holding onto fat, and if you are losing weight, you're probably losing 60% of it's probably fat, but 40% muscle. So all this stuff that then causes metabolic adaptation, that really makes a mess. When I was writing Sugar Impact Diet, I started looking at metabolic flexibility. I heard about it from my buddy Mark Sisson, and I was like, this makes so much sense to look at because one of the things I saw, and I'd love you to talk about this with the cyclical keto idea, is I saw people who were going into ketosis and stuck because now their bodies didn't know what the heck to do with carbs. Then you see vegans who are eating very low protein diets who are stuck because now their body isn't producing the hydrochloric acid it needs to do. You know, your body is such an adaptive machine, which is good and not good. So let's talk about metabolic flexibility, how you deep dove into that. The other thing I want to throw into that is like, how would someone know if they were metabolically inflexible?
By the way, I met Mark for the first time about five months ago down in Florida, and it was wonderful meeting him also because once again, he's been in this space. I've never crossed paths with him.
He's my oldest friend in that, like, we've known each other since we were in our 20s.
We had a great time. Jeez, this is a side. I'll get to your question. Wouldn't it be amazing if we took three or four of us who've been doing this for a long time and collaborated and like had a big project together? That would be a lot of fun, by the way.
Let's talk further on that one.
Yeah, for sure. Okay. Metabolic flexibility. This is how I look at it. Okay. Your body needs fuel. Two of the biggest fuel sources for your body are carbs and fats. As you know, they are macronutrients. They're two of the three macronutrients. And the reason why we call them macronutrients is because the body needs them in large supply. So people who say that they don't need carbs, that they're not going to eat carbs, that is completely contradictory to sound nutritional advice and working of our bodies. We need carbs. In fact, the brain's number one fuel source is Glucose. Let's look at carbs and fats. If we use those as our two primary sources of fuel, our energy, can we use them? Can we burn them efficiently to be able to take the energy and the body do all those processes? I mentioned all the work that the body needs to do. What research has shown is that a lot of people can only burn one or the other efficiently. They can burn carbs really well, but not fat, or they can burn fats really well and not carbs. So imagine a switch, and the optimal situation for metabolic health and metabolic flexibility is to be able to take this switch, burn carbs when you want, burn fast when you want, and to be able to very easily go from one or the other based on what you're seeing. If you sit down to a big plate of pasta, you want your body to be able to burn those carbs and be able to use that energy well. If you sit down to a fattier meal, maybe something like salmon, you want your body to be able to burn the fat very well. Okay. Some people can only burn one or the other, so they are metabolically inflexible. The person who is metabolically flexible can burn whatever they see whenever they see it. So the ideal situation is to get your body in a position so that if it sees carbs, burns the carbs. If it sees fats, it burns the fat. If it sees both, it burns them both. Unfortunately, we are stuck. That switch that I'm talking about, that metabolic switch, is stuck either heavy on the carbs, heavy on the fats. And what I do with the Metflex diet in this book is I try to unstick that switch and get your body acquainted with carbs. For those who know a lot of keto, or for those who've been eating mostly carbs, acquainted with fats and protein, that is kind of the gist and the foundation of the Met Flex diet.
All right, and how would someone know if they were either inflexible or flexible at this point? You know, besides using maybe one of the breath tests that shows you what.
You'Re burning, there is a scientific way to do it in a lab that obviously is not available to the vast majority of people. Page 10 in the book, I say to people, these are your signs of metabolic inflexibility, feelings of anxiety and or depression, a need for some type of stimulant like coffee to function, difficulty losing fat, constant cravings despite recently eating, fatigue, sluggishness or crankiness when not eating or during your fast, fatigue after a carbohydrate rich meal like pasta and fluctuating blood sugar levels. These are the most prominent signs that it's very possible you are metabolically inflexible.
I'm going to assume my world where I got connected up with Mark Sisson early on is we were both exercise physiologists, right? And we were like, as far as I know, Mark and Body by Jake and me were the first personal trainers way back when. So I'm an old exercise physiologist and I feel like exercise is finally getting its due. And so I think about all of this shifting of fuel sources and it takes me to exercise and I actually, for a while there was playing around with wearing a CGM during exercise to see how high I could get my blood sugar to go, and then blowing into a lumen afterwards, going right on like, I used a ton of carbs. And that's what I'm trying to always explain to people because I think we've got such a naive view of everyone wants to be in fat burning. I'm like, not when you're working out really hard. Like, you've gotta be a hybrid car and be able to use the right fuel in the right situation. If there is someone chasing me, I do not want to have to be relying on fat. I'm done. They got me.
This is very important, by the way, what you're saying right now. You and I obviously understand it, but the average person, this is important information. Fats and carbs both fuel the body. However, there are different times and different speeds at which these fuel sources become available. Burning fat, we all like to do that, we all want to do that, is a very slow, relatively speaking, laborious process. The body really has to work to burn that fat, whereas burning carbs, which is why carbs are the number one fuel source, because the body wants to do things quickly and efficiently, which is why carbs are fast. It's faster than burn carb. We talk about fast carbs when you are exercising. Depending on the level of intensity of your exercise and the type of exercise, carbs may be used more frequently or fat may be used more frequently. And this is very important. So like you said, if you need a quick burst of energy, you don't want to rely on fat for a quick burst of energy for an intense getaway from someone. Not going to happen. You need your carbs to do that. However, if you are exercising, it's less intense over a longer period of time, then you can very nicely get into that fat burning zone. So the body fluctuates between burning fat and burning carbs. And that is why when people talk about what do I eat before my workout, what do I eat after my workout? I say to them, hold on for a second before we go there, tell me what the goal of your workout is. If the goal of your workout is building muscle mass, that is a different equation, a different recipe for what you eat and when you eat it. If your goal is you want cardio, you want really intense cardio, that is also very different. You want to burn a lot of calories. That's different. And so, yeah, it's very important for you to understand that carbs and fats, while both good sources of energy, are used at different paces for different reasons by the body.
I'm glad you pointed that out because you get people saying, okay, well I. I'm doing a fast workout cause I want to burn more fat. And I go, but you're going in and doing a high intensity workout, so go for a walk. If that's the case, let's like dig into this program then. And again, kind of what I see with this program, you call it becoming your own metabolic mechanic. I really see this as being able to use different types of diet tools to see how your body works and to really paying attention to that. I know you have a workbook in here as well, and that allows them to start to track into it. So let's just start like someone's just starting out with what happens first.
I am a big believer in graduating into things. I just, that's just been my system. I wrote one book where it was actually radical right from the beginning, and that was for people who wanted to be. But I am a big believer that people need to work their way into a program for all kinds of reasons. Psychological, physical, you name it.
Motivation to have more success so they don't bail out in three days.
Absolutely. 100%.
I know they all want to jump into the really super hard, super fast program and then they all leave.
That's exactly right. That's right. So in the Metflex diet, what I do is I spend the first couple of weeks allowing you to really get acquainted with carbs. And there's some fat, but it's really card heavy. I want you to get adjusted to the carbs to eat better carbs. By the way, it's not a bunch of danishes and bagels though. I love both. But really good, healthy carbs. There's pasta in there and there is some bread, by the way. But I want the first couple weeks Is we are gonna do some carbs. We are also gonna do protein, but we're also gonna do some intermittent fasting. Okay. Because I'm a big proponent of intermittent fasting and I know that the literature kind of goes back and forth every week. Is it good? Is it not good? I get it. That's science.
But, well, it depends what you're using it for again, like.
Right, Exactly.
Doesn't it go to that? And I'm glad you said it was high carb, low fat, since we know the beautiful food guide pyramid of high carb high fat, what it's created in our obese society.
Yep, absolutely.
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So the first couple weeks, that's what we're doing. We are really getting the body acquainted to learning how to use carbs in conjunction with. With the intermittent fasting. You said it very well. You said different tools in conjunction with the exercise. All three important what you eat, when you eat it, and how you move all help. You could choose just one of those three components and find some success. But if you want to find the most success and you want to have the biggest impact on your metabolism, let's do all three at once. And that's why I think this program has been so effective for so many people. They, you know, people lose up to £20 in six weeks. That is a big number. Everyone's not going to lose 20 pounds because we all lose weight differently. But when I use this program on a thousand people in my Facebook group, people lost up to 20 pounds. The average weight loss was 14 to 16 pounds in six weeks. As you know, JJ, those are big numbers. And I'm not saying everyone's going to lose that. And I'm also not saying you have to lose that much because if you lose it slower, it's fine. Also, I'm just telling you, the reason why I think it works so well is because it's taking different tools and putting them all together.
It's an exponential. Like you, you said, it's so Important. Sure, they could just do the diet or they could just do if, or they could just do exercise. But one plus one is not three here. It's like a thousand. Walk us through the if piece of it. How do you view if? I gotta tell you, like intermittent fasting, fasting, trf, time restricted feeding. I'm like, I wish we had very specific parameters for each one because they're all over the board. Right. To me, a lot of either time restricted feeding or intermittent fasting is just the way we should be eating. I don't know when they just decided we should eat immediately when we wake up and eat right before bed. Well, I remember it was in the 80s when they took fat out. Then we had to eat all day long and have snacks and go to bed.
I wrote a book based on that too. Okay, here's my take on intermittent fasting. Intermittent fasting, the overall goal, I'm speaking general. The overall goal, in my opinion for intermittent fasting is to at some point drive your body into fat stores and use fat for energy. Instead of using carbs for energy. So burn through your carb stores because we store carbs in the form of glycogen. Burn through all your carb sources, which actually burn pretty fast for most people. Burn through your carb sources and then say to your body, oh, now what are you going to do? And the body says, well, I don't want to do it, but let me try to get into this fat, because that is energy and it's available to me. It's just a lot of work to do it and it takes a while to get it done. That in general to me is what intermittent fasting is really saying to the body. Okay? Changing fuel sources, restricting your calories from food and trying to go into your fat, your stored fat. Okay? Now intermittent fasting has been shown on page 19 in the Metflex. Weight loss, decreased inflammation, reduced insulin resistance, decreased belly fat, preserved learning and memory functioning, improvement in asthma related symptoms. As you say, if is all over the map and people have made other claims. Those are the claims that I feel comfortable with after reading different research that I can say intermittent fasting can help. Now here's the issue. The issue is that there are all types of intermittent fasting. All versions, like keto, all versions. So what I did is I said I'm going to use in the Metflex diet three of the bigger, more researched, more used strategies of if you mentioned one trf, time restricted feeding. So we're gonna do some time restricted feeding during the Plan. The next One is the 5:2 method. Five days of relatively normal eating and two days of low calorie eating. And then the third method, which I actually have never used before until this book, but I really like it, is the alternate day method where you have one day of relatively normal eating, one day of 500 calories. Normal eating, 500 calories. I think that's a really fun, challenging, but extremely result oriented week when you go back and forth like that. So in the Metflex diet, I use all three of those. Okay. But once again, jj, the idea behind all three of them is to get your body into a place where it's pulling fat as a fuel source. Which is why a lot of the research for IB says that it's one of the very few strategies that you can say actually can reduce belly fat.
I love this too. Bat and HIIT training. And I know you're a big fan of that. And cold. I have a cold plunge. I'm in Florida. We're moving our cold plunge inside to get it colder. One of the things that I've always been obsessed with this caloric variability. I feel like we don't talk about it enough. And I think a lot of people go wrong with intermittent fasting is they just now they're gonna do it this way every single day. And I'm like, well, I think there's time. Restrictive feeding principles we should be doing every single day. Like stop eating three to four hours before bed, Wait before eating. When you wake up in the morning, let your pancreas wake up. That makes obvious sense. But then I see the people that are like, I only eat one meal a day or I only eat two meals a day. The problem is now your body's gonna downshift into that expectation when what you just described of like, we'll do it this way, you know, every other day or five days and then two days. So your body's going has to shift, has to figure it out. Isn't going to make a downshift that's permanent is the thing that makes sense to me.
I just say this, by the way, because I call it diet confusion. Like in a gym you say muscle confusion.
Just like the muscle confusion. Yep.
Muscle confusion. Yes. And my book Shred the big seller that I had Shred the revolutionary diet. The premise of that book was I put you on a calorie roller coaster up and down. I did that book. Geez, I don't know, maybe 10 years ago. And everyone kept saying, why is this program working? Because the food Looks regular. You can have pizza. How can you have all this stuff? What they didn't realize was my secret sauce was, your calories are going up then down, up then down. Because I didn't take away all of the fun foods in shred. People didn't realize that their calorie count on day eight was like maybe half the one on day two. They just didn't realize it because they were. It's a distraction technique, and that's why it was so effective. But to your point, I said to people all the time, if you are going to do one style of if also try another style. Because the body is a great adapter. Once the body gets acclimated to whatever challenge you put in front of it, the body is going to figure it out. And the body also wants to conserve as much energy as possible. That's what the body does. The body would like to sit down on a couch and just relax because it wants to conserve energy, doesn't want to expend energy. We have to make the body expend energy, which is why we talk about doing exercise. The other part of it is if your body knows what's coming all the time, your body says, I got it, I got the plan to defeat that. And then it doesn't work anymore. Try different methods of intermittent fasting, or even if you don't follow my program or anyone else's program on your own, vary your caloric consumption. Go a day of really low calories, like, low calories, and then a day of normal calories, not 4,000 calories. Okay. Let's be honest.
Okay. That's where food tracking's so good because you'll see really quickly.
Here's another thing that people do. Oh, it's a normal day of eating. Intermittent fasting says one day normal, one day low. The normal day I can eat whatever. No, no, no.
Oh, my gosh. Remember the. I actually was on the Today show. I'm trying to remember who I was on with because his book was like, you can eat whatever you want within eight hours. I was doing Sugar Impact diet. So I'm like, you need to lower your sugar impact. He's like, no, you don't just eat it in this eight hours. I'm like, do you know what kind of damage I can do in eight hours? Like, that is a lot of time. Besides the fact of all of the inflammatory stuff it starts and everything else.
That's why in the book, I use all three methods based on the week. So based on the week, I use all three Methods and then I slide into some carb cycling, which is I do some weeks where you're doing two days of carbs, carb loading, load, load, load, load, load, and then five days of keto and then get out of it. Two days of carbs, load, load, load, five days. A gift. Because research has shown that you can call it carb loading, you can call it keto cycling, cyclical keto, all those are the same thing. Research has shown that getting in and out of keto actually has good benefit. I've never been a big fan of long term keto. I think that yes, keto can get you results as far as losing weight. But I've always believed that long term keto and eating that way for a long time is not at the end of the day the healthy way to do it. I think it's too much protein.
Totally, totally agree on the too much fat. You know what's so, so interesting? If you look on YouTube, it's like all the big influencers like why I stopped keto. You know, So I totally get that. It's kind of reminds me of the book title of what got you here won't get you there again. It's a tool. This idea of using it to be able to teach your body to flip in between fuel sources is super intriguing. Now we are yakking. I could go on all day with you. We'll have to do this again. But we have to address exercise. We've danced around it a little bit. We kind of mentioned hiit and vat fat. But let's talk exercise and how you prescribe exercise.
Okay? So by the way, those who are listening or watching you can join my group. Facebook group. It's the name of the book. Met Flex diet. That's my group. There are a lot of fake groups out there. Make sure you just put, get the real one.
We'll put the link to. We'll put the link in the show notes so you don't.
That's me. We got 21,000 people doing this. I say that because we also exercise as a group too. By the way, we do exercise sessions. Yeah, here's my take on exercise. Once again, how you exercise really has to match your goals. Okay. We got to start with the goals. People who say, hey, Dr. Ian, I just want to lose weight. What is the best exercise to lose weight? If I get that question, I will say to them that for my money, if I had to choose one strategy, hiit is the strategy. High intensity interval training. I can give you a 20 minute workout using HIIT that can burn more calories and have greater impact than an hour and 20 minutes walking on a treadmill. Steady state, okay for weight loss, but if someone came to me and said, Dr. Ian, I really want to tone up and I want to really start burning more fat, well, that then would be a lower intensity program mixed occasionally with some hit. But I, I want to keep you more in a lower intensity to make your body to go and stay more in that fat burning zone. The other thing I will do, by the way, and I think that a lot of people, and particularly women, but I'm happy to see more women doing this when I go to the gym, is that resistance training is important. You have to build.
Say that louder. Say it louder.
Resistance training is so critical. Jj, look at your muscles. I'm not saying it's because your podcast that to me photographed is what I would post and say. This is what we are after. We are not after huge, bulky women.
Huge, bulky muscles. I lived. I am 60 years old. I am 60 years old. I live super heavy, heavy, heavy weights, women. I have been working with men and women doing weightlifting since the early 80s. I used to take them to field trips at Gold's Gym in Venice. And the women would get so scared. I go, listen, unless you want to take steroids, I can't get you bigger. You will build muscle.
It'll.
It's metabolic Spanx. It's going to hold everything in tighter. I have never once worked with a woman who got bigger. It is not possible. I mean, unless you're gaining a bunch of fat because you're gaining a bunch of weight, but that's not happening. You burn muscle, you build muscle, you burn more fat, you get tighter, you get smaller.
Here's one of the issues. One of the issues is that women would say to me all the time, Dr. Ian, you don't want these huge. Looking like a man.
Massive.
Let me tell you something. In order to get that kind of muscle, you have to be on steroids. You have to be lifting six hours a day. That's a whole nother being the average person. A woman is never going to look masculine with these huge shoulders. Doesn't work that way. But they can look like you, which is muscle height. They're lean, right? The lean mass nice and tight. And that's what I try to get people to do. But the only real way to do it is not walking on a treadmill. The way to do it is you have to throw in some resistance training. The muscle has to be Worked in order to grow. And by the way, doesn't mean even though you can lift heavy weight. I lift heavyweight.
You can lift heavy weight, but it's heavyweight for you. So, you know, like heavyweight for someone right now might be doing a wall pushup. It doesn't matter. It's whatever for you that you can't keep going and doing more of.
That's exactly right. So my prescription for people and in the Netflix diet, the prescription is based on the week, based on what you're eating. So I get more kind of granular. But in general, my prescription for exercise for most people is, let's start with the number of days. I'm not greedy. Give me four days. Would I like five? Yes. I'll take four now. If you give me those four days, give me at least two sessions of HIIT a week. I'd like three, by the way, but at least give me two sessions of hit. Give me two sessions of resistance training. And at least one or two of those days, give me a double. I want a day where you do resistance and a day where you do hit. Right. I want one or two days like that. Because I am a believer that when you change up the challenge to the body, the exercise challenge to the body, your body responds in amazing ways. If someone has a workout where they just go in every day, I say this all the time in the gym, and I feel so bad for these people because I don't do this. My wife has stopped me from doing this. I want to say, oh, my goodness, you spend so much time here in the gym and you are wasting so much time because what you're doing is not going to work. It has not worked. But the point is that they're doing the same thing all the time, and you just can't do that. The body becomes acclimated, adjusted, habituated to what you're doing, and then it stops having an impact because the body figures out how to work against it. And so if someone said to me, you could only write one prescription for better health, what would that be? Exercise. Heck, yeah, exercise.
I know. That's why I feel like us exercise physiologists are getting our due. Is now where all the focus is on longevity. You look at every single biomarker, every single hallmark of aging is like exercise, right?
Look at you. People will look at my ID and not believe my age. They will look at you and not believe your age. And they say to me, what do you do? Listen, I eat healthy, but I don't eat crazy healthy. I eat Normal, healthy. But I exercise all of the time.
Maybe that's what we'll do. We'll do some exercise videos. That was super fun. Super duper fun. Yeah. I love that you're saying all that because, hey, I love it when people just get out and do anything, get out and move. But I feel like we're doing people a disservice because then they think, well, I'm walking. I'm like, you know what? Walking's controlled falling. This is what we are supposed to do as just part of life. You gotta start lifting things. Otherwise, I'm gonna be lifting you off the toilet. That's not what we want.
And jj, guess what? When I was in the hospital, I was doing rehab. And when we had patients on the floor and the patients had injury and they're rehabbing, who succeeded and came back the most and the fastest? The manual laborers, the butchers, the landscapers, the sanitation workers. They were able to recover from their injuries a hundred times faster than the bankers, the lawyers, Holy smokes. Because guess what? They were outlifting. Moving. You got to make the body work. A guy just said to me, he said, doc, you have to drive your car more. I have a classic car. You have to drive it more often. He said, letting your car sit for six months is hurting the car. And he's right. Letting your body sit for extended period of time is hurting the body. Same principle.
Amen. Oh, wait. Well, this obviously is just our start. I don't know how this took so long for us to get connected. And if you're coming to Florida. I actually moved to Florida partly because Mark was talking about it so much. And we got a bunch of us now over there in Florida. We got Colleen and Jason Wakab. You must know them from mindbody Green and Dan Buettner, Blue Zones. Yeah, we're getting a little crew.
So what side are you on, though?
I'm over in Tampa.
I love Tampa.
My husband's from San Diego, and when I met him on Match, I'm like, I want to move back to Florida. He goes, I live in San Diego. Like, oh. Anyway, we came and visited, and he fell in love with Tampa. Felt like it was San Diego. And of course, we move here. And immediately after we move here, we win the super bowl, then we win the Stanley Cups, and he's like, champa Bay. So it's been a good booth. Yeah, it's been super fun.
I'll come see you. I come to Tampa at least two or three times a year to do on my tour awesome.
Awesome. Awesome. Well, I'm actually building out. It's just being finished my home gym, so I can do video in it. And so we built a whole, like, whole other floor where we could just have all this cool stuff. Because I got so fired up about getting in my best shape at 60, got down to 11% body fat, and I'm like, now what can I do? Now I'm gonna really go for it. Like, battle ropes and, you know, let's go. The thing that happens as we age that people don't talk about is everyone's talking about losing muscle. We lose power.
Yes.
And so I was like, not now. I'm not losing that, and everybody around me is not losing that. So we gotta throw things. We gotta not only lift heavy things, we gotta throw heavy things too. So you gotta do one where it.
Says, this is the new 60.
Yes. 60. And being, you know, strong to me, is the new skinny. Like, move over skinny. I'm worried about all the women who, for their whole life have been working on being skinny, because I think when they get into their 50s and 60s, they're just set up for problems because.
Oh.
So anyway, that's a whole nother thing, I'm telling you.
We got to do another podcast that is so dangerous and so bad, and.
We just got to get off of that. We got to have people doing Dexa scans. We've got to have people focusing on strength instead of focusing on skinny. It's so bad for women's psyches anyway. It's just ridiculous. So I'm on a mission on it. Sounds like you are too. So we'll go together. That will be fun.
Okay.
And I just want to remind everybody, we'll put a bunch of this in the show notes. Obviously, there's so much, like all your books and your fiction books. Who knew? But also your Facebook group, so everybody can make sure they're in the right group joining you and any other resources you have. So be sure to check my show notes too, and your Instagram.
Dr. Ian Smith. Spell the doctor out. I, a N. Smith. Make sure you get the one, the blue check mark. Cause that's me.
Okay, cool. So we will make sure we get all that in there so you can hang out with Dr. Ian. And then if you'd like us to do a workout program together, just let us know. All right, awesome. Thank you.
Thanks, jj.
Be sure to join me next time for more tools, tips, and techniques you can incorporate into everyday life to ensure you look and feel great.
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Hello listeners, this is Anne Bogle, author, blogger and creator of the podcast what Should I Read next? Since 2016, I've been helping readers bring more joy and delight into their reading lives. Every week, I take all things books and reading with a guest and guide them in discovering their next reading. They share three books they love, one book they don't, and what they've been reading lately, and I recommend three titles they may enjoy reading next. Guests have said our conversations are like therapy, troubleshooting issues that have plagued their reading lives for years and possibly the rest of their lives as well. And of course, recommending books that meet the moment. Whether they are looking for deep introspection to spur or encourage a life change, or a frothy page turner to help them escape the stresses of work, school, everything, you'll learn something about yourself as a reader and you'll definitely walk away confident to choose your next read, with a whole list of new books and authors to try. So join us each Tuesday for what Should I Read Next? Subscribe now wherever you're listening to this podcast and visit our website what shouldireadnextpodcast.com to find out more.
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