Pod Insights Habits and Hustle Episode 418: Dr. Jason Fung: Why Calories Are Not the Key to Weight Loss About this episode Listen to the full episode here: https://youtu.be/nncEWmQFiSo?si=GanDDq9g0w1qDtE4
There's a common belief that weight loss is simply about "calories in, calories out" - but according to Dr. Jason Fung, this is actually false and misleading information.
In this bonus episode of the Habits and Hustle podcast, I talk with the author of The Obesity Code, a renowned expert on obesity and intermittent fasting, who explains that there is much more to gaining or losing weight than just the number of calories consumed. It's not only about the energy in the food, but critically, it's about what your body does with that energy.
We dive into the complex role of hormones and common myths around calories to make a compelling case for why we need to look beyond overly-simplistic "eat less, move more" advice to understand obesity and weight loss.
Dr. Jason Fung is a New York Times-bestselling author of many books including The Obesity Code and The Diabetes Code. He completed medical school at the University of Toronto and a fellowship in nephrology at UCLA. He is the co-founder of The Fasting Method https://www.thefastingmethod.com/, a program to help people lose weight and reverse type 2 diabetes naturally with intermittent fasting.
What We Discuss:
"Calories in, calories out" overly simplistic Body stores or burns calories based on hormones Different foods have different hormonal effects Insulin drives fat storage; spiked by certain foods Protein: insulin and satiety effects Processed carbs especially fattening Foods' hormonal impacts key, not just calories …and more!
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Find more from Jen:
Website: https://www.jennifercohen.com/
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Find more from Jason Fung:
Website: https://www.doctorjasonfung.com/
Instagram: https://www.instagram.com/drjasonfung/
Transcript Speaker names marked ? are inferred from speaking time and the show’s known hosts — they are not voice-verified.
0:01 Speaker 00 Hi guys, this is Tony Robbins. You're listening to Habits and Hustle. Crush it.
0:07 Jen Cohen? Hey friends, you're listening to Fitness Friday on the Habits and Hustle Podcast, where myself and my friends share quick and very actionable advice for you becoming your healthiest self. So stay tuned and let me know how you leveled up.
0:29 Jen Cohen? Before we dive into today's episode, I first want to thank our sponsor Therasage. Their Trillight panel has become my favorite biohacking thing for healing my body. It's a portable red light panel that I simply cannot live without. I literally bring it with me everywhere I go. And I personally use their red light therapy to help reduce inflammations in places in my body where honestly I have pain. You can use it on a sore back, stomach cramps, shoulder, ankle. Red light therapy is my go-to. Plus, it also has amazing anti-aging benefits, including reducing signs of fine lines and wrinkles on your face, which I also use it for.
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1:51 Jen Cohen? We've always heard, and me coming from the business background of health and fitness, that really it's about the calories you bring in versus calories out. And you're saying if you want to lose weight, that is actually, that's actually not correct information. It doesn't work as simplistic as that. Why, can you just kind of talk about that a little bit more?
2:12 Speaker 02 Yeah, absolutely. Um, so the whole idea with calories in, calories out is that, um, you know, it, it, it makes a few false assumptions. First of all, people look at it and um, they say, you know, calories represents one part of the foods that you eat. That is the energy that's contained within that food. Okay, but when you're trying to gain or lose weight, there's actually much more to it than simply the energy that's contained in that food. Um, so it's not just the energy, it's what your body does with that energy, right? So if you take a hundred calories of cookies, for example, or brownies,
2:56 Speaker 02 versus a hundred calories of, you know, salad or broccoli or, you know, salmon or whatever. The, the body can choose what to do with that energy, right? So you can either store it as fat, or you can burn it and use it for energy. You can generate body heat, for example. So simply, um, you know, taking in that energy doesn't mean that you're going to store more fat, because if your body simply uses it, then you're not going to store fat. However, on the other side, if you take in a hundred calories of cookies and your body immediately shove, you know, shuttles it into body fat, which is simply the storage form of calories.
3:36 Jen Cohen? Mm hmm.
3:36 Speaker 02 Well, you don't have any energy. So then your body is going to have a hundred calories less energy, because you've put it into storage, right? And so therefore, you're going to be hungry, or you're going to generate less body heat. None of which sort of, you know, um, you know, breaks the laws of thermodynamics. Because people always say, oh, it's thermodynamics, it's thermodynamics. And they act, anybody who says that clearly doesn't understand thermodynamics in any way. Because remember that it's the energy balance equation is body fat equals calories in minus calories out, and that's always true. But there's three variables there. There's body fat, which is storage, there's what goes in and what comes out, right?
4:19 Speaker 02 So if you take less in, for example, you're reducing your calories in.
4:26 Speaker 02 You don't necessarily reduce body fat. What could also happen is that if calorie what comes in goes down, what goes out? That's energy expenditure can also go down and your body fat can stay the same. So that is one of the choices the body can make. But it depends on the hormones within your body. Right? So if you're eating less, but you're burning less. Then your body fat is not going to go anywhere. Right? And it doesn't break the laws of thermodynamics. So simply eating less doesn't automatically translate into lower body fat. It depends on what your body does with it. And that's all about the hormones in your body.
5:07 Speaker 02 Right? So we know, for example, that insulin is a hormone that promotes storage of those calories. So if you simply take foods that you know, have a very high insulin stimulating effect, your body is going to want to store that because that's what you've told it to do. So therefore, what happens is that you don't have energy to burn because you've stored it away. So just like if you have, if you go to the grocery store, for example, and you take that food and you immediately put it all into your freezer. Well, you have nothing to eat. Right? So you're either going to have to eat less or whatever. Right? Same thing. If you take those calories, store everything away.
5:49 Speaker 02 You have no energy. So then your body is going to burn less because it has no energy to use. So that's one of the most important things. When you eat, the food contains not just the calories, but also contains information as to what to do with those calories. Right? So it's not this simple in and out.
6:09 Jen Cohen? I have two questions. Is that why when people are in their, in their, when they hit like middle age or over, over forty, they tend to have more uh body fat? Not is because, you know, a lot of times your hormones are changing and you have uh it's all about the hormones and they're, and they're gaining a lot of weight in their midsection. And what they try to do to offset it is eat less. But they're still not losing that body fat, right?
6:37 Speaker 02 Yeah, because it's really depends on and and it happens to everybody. So everybody notices this, right? Right. If you look at teenage boys, they are eating a lot. And they're not generally overweight. I mean, Right. if you look at sort of middle aged and older men, they're more overweight than sort of twenty year olds. Right. Those twenty year olds, if you've ever had a teenage boy, they eat a lot of food. Yes. Um, and everybody knows that. So therefore they must be also burning a lot. And that's probably just the stage of life they're at. There's the hormones and their energy and what they do, their lifestyle, that kind of thing. So i- i- it plays a role. But the the the the point of the uh the whole uh thing about calories is that you have to really look beyond the calories.
7:21 Speaker 02 Um, and you really have to look at what the information contained within that food is as to what your body's going to do with it. So if you are uh taking certain foods that have more fattening, then you're, you know, it's because of the hormonal response to those foods. That is, as soon as you put the cookies in your mouth versus when you put broccoli in your mouth. The hormonal response of our bodies is completely different. We know that. That's that's just science, right? Right. So we have to pretend, you have to pretend that those hormones don't play any role in body fat, but it does. Everything depends on the hormones. That's how our body works. So this whole idea of calories is completely unphysiologic.
8:06 Speaker 02 That is, there is no, no system within our body that simply monitors the calories in, calories out. We actually have no way of measuring how many calories in. The only way our body knows, should I store body fat? Should I burn it and generate body heat? Should I, you know, uh, have too much sugar and become diabetic? The only way our body knows what to do with it is the hormones. And that's really what you have to focus on. And it doesn't break any laws of thermodynamics. It doesn't go against, it doesn't mean you can eat everything you want. The only thing it means is that certain foods are more fattening than other foods. And, you know, that's sort of common sense because.
8:47 Speaker 02 Your grandmother would have told you like, nobody gets fat eating broccoli. It's just doesn't happen. But the people, all those sort of scientists who are sort of real, it's all about the calories sort of thing. They'll try and convince you that, you know, well, a hundred calories of cookies is just as fattening as a hundred calories of broccoli. But it's not true in any way. Cookies are very fattening. Everybody knows that. Um, but yet somehow they tried to convince everybody and did, they were quite successful to, to, to a certain degree. That they did convince everybody. So there are doctors out there saying, oh, you could eat ice cream for dinner and not get fat as long as you count your calories.
9:29 Speaker 02 It's like, well, you know, some calories are more fattening than other calories. If you eat a block of wood, it has a hundred calories, but it doesn't matter. Your body doesn't absorb it. It just goes right through you. Your, your body can't process it. So it's not the energy. So it's energy plus what you're supposed to do with that energy. And that's really what's important.
9:50 Jen Cohen? So there's a couple, you've said a bunch of stuff that I'm very much want to ask you about. So the first part of this is, is it because your body, it's what your body does with that particular calorie, right? Cause you could have a bunch of cookies, a hundred calories of cookies versus a hundred calories of broccoli. Your body metabolizes it different. So you, there's a couple of things. So I heard you say that, so the trick, by the way, is to, not the trick. The, the thing is to keep your ins- insulin leveled, right? Not to spike your insulin. So are you saying that like cookies, processed food, of course, sugar, all of those things are obviously spiking your insulin?
10:33 Jen Cohen? But I think I heard you say on someone's podcast, um, or even in your book, maybe that protein can even spike your insulin, which is something that I've never heard anybody say before. Is that, like, how is that possible?
10:45 Speaker 02 Yeah, protein can spike your insulin for sure. Um, but it has other effects. It, it also, because insulin goes up, but then other hormones go up like glucagon. It ha- it doesn't tend to have any effect on. Blood glucose as opposed to carbohydrates where it does have a big effect. Um. But then there's other effects. I mean, it's it's it's the sort of totality. If you look at protein, for example. There's other effects. If you eat protein, you're going to stimulate peptide YY, which is a satiety hormone. And it's going to make you not want to eat. That's why they have those, you know, contests where you. You know, you eat a hundred and twenty ounce steak, we'll give it to you for free. They're not giving away a lot of free steaks.
11:26 Speaker 02 Because those satiety hormones are just so strong that you can't force yourself to eat that much uh meat. Because of the protein. So there, you know, yes, insulin is going to go up. But if on the other hand, your body is going to naturally stop eating it. Like, you know, if you've ever gone to a buffet and just been super, super full and somebody said, here, have another pork chop, you go. You know, I'm gonna throw up, right? That's just the way it is. So therefore. It's going to naturally sort of regulate itself and that's why protein's not particularly fattening. A lot of people eat high protein diets and and and do very, very well. Carbohydrates, of course, is a little bit, especially processed carbohydrates.
12:09 Speaker 02 Natural carbohydrates, probably less so, but processed carbohydrates to a big extent is the big problem. And I don't think that's terribly controversial. I mean, it's simply, you know, uh, sugar. Refined uh refined grains and stuff, a lot of stuff that, you know, we probably accept that is not good. Um, you know, the whole point is that it's it's it's the the foods that you eat. Are important in many different ways, other than just the calories. So you do have to look at these. These these these other things because they're really just really, really important.
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