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Bert Martinez:
Doctor Fung is on the show and he has not one, not two, but three bestselling books that we’re going to be diving deep into. But what got me excited about getting him on the show is the fact that he has found almost what I would refer to as an ancient recipe that will reverse diabetes, will reverse multiple health conditions. Dr. Fung, welcome.
Dr. Jason Fung:
Thank you. Thanks for having me.
Bert Martinez:
You bet. All right, so give us a little bit about your background, because my understanding was you were in, I don’t know what the technical term is, the medical term, but you were in kidney functions and then you somehow fell into this health, weight loss, health area. So talk about that.
Dr. Fung:
Yeah, so kidney disease is my specialty. So I did medical school in Toronto, then I went to UCLA to do nephrology, which is a specialty in kidney disease. And the thing about kidney disease is that the most common cause of kidney disease is actually type 2 diabetes. And type 2 diabetes, for many, many years I was taught, is a chronic and progressive disease. But the thing is that even as we’re saying it, we knew it was just a big lie. Everybody knew that type 2 diabetes was actually reversible. If you lost weight, then most of the time your kidney disease would either get much better or go away. In other words, it was reversible.
Dr. Fung:
It wasn’t sort of a one way street that we are basically told, because after all, if a friend of yours said, oh, I lost, you know, 50 pounds and I got off my diabetes medication, you’d say, oh, that makes sense. Right? You wouldn’t say, oh, you’re such a liar. Right. So we knew it was actually a reversible disease. And that’s where I sort of started to get the inkling that the way that I was taught was, and, and all doctors are taught is not actually, you know, the best way to treat patients. Because the thing about it is that if you think about diabetic kidney disease, you think about the kidney diseases caused by diabetes. So you have to reverse the diabetes. Right.
Dr. Fung:
In order to reverse the diabetes, you had to lose weight. So really that was the sort of chain. I don’t want to treat people after they get their diabetic kidney disease because all you do is put them on dialysis and that’s it. Right. What I wanted to do was treat the, you know, diabetes, which is. Then they don’t get the kidney disease. In order to treat the diabetes, you had to get people to lose weight, which was odd because it was never a focus of diabetes medicine. Right.
Dr. Fung:
Which is super strange. Right. So they. They actually just changed the American Diabetes association in the most recent update. So 2025 just put weight loss as an important factor. Like, 2025, like, 50 years after we understood that weight loss was actually important. Like, every single person, every doctor, every nurse, every patient knew that weight loss was important. But because there’s no drugs and no pharmaceuticals pushing weight loss, nobody cared, like, two bits about it, right? So that’s where I wrote the.
Dr. Fung:
You know, so then, then that’s where I really became interested in weight loss. And that’s where I wrote the obesity code in 2016, which was that the way we think about weight loss, which is calories in, calories out, is actually completely wrong. Like, the way we think about it is actually completely backwards. Everybody thinks, oh, if you just eat a few less calories, you’re going to lose weight. And that’s what we all think, but it’s actually not true. The types of calories makes a big difference. The way you eat those calories makes a big difference. All of those make a big difference.
Dr. Fung:
That is, eating 100 calories of cookies is very different than eating 100 calories of broccoli. So how can you just say it’s all about the calories? Right? Because the nature of those calories makes a difference. The minute you eat those calories, your body responds to them completely differently is measurable, Right? You can measure the hormones that are released in response to cookies versus broccoli. So why would you pretend that doesn’t matter? Like, I don’t understand why you would pretend that these things don’t matter. Right? So that’s. That’s where that came from. And then I talked about intermittent fasting, because, again, at that time, you had to understand that at the time I wrote about fasting in 2016, people thought it was the stupidest thing you could do. It was super harmful.
Dr. Fung:
It would kill you. You know, even if you’re like 500 pounds, you need eat 10 times a day. And it’s like, why. What do you think is going to happen when you keep eating all the time? You think you’re going to lose weight while you’re putting all that food in your mouth? Like, why, if you have all those calories stored as body fat, why can you simply. Why couldn’t you simply not eat for a while and let your body burn off the stored calories? Right? Isn’t that obvious? Sort of like, if you have, you know, a refrigerator that’s so full of food that you can’t even barely shut the door and you Say I need to go to Costco five times a day and if I miss a single time, oh man, it’s going to be bad, right? It’s the same thing. People had all this calories stored as body fat. And at the same time, every doctor, every dietitian was saying, you must not skip a single meal because you’re going to kill yourself. Like, what are you talking about? Like, how is this scientifically even legit? Like, is it simply a case where people just repeat these things so often, these sort of ridiculous facts so often that they believe them? And I think that’s really what happened.
Dr. Fung:
So anyway, that’s how I got into, really into weight loss, into fasting and that thing. Because all of these things are important because as doctors, we get away from, you know, diets. We don’t actually learn about diets. We don’t talk about diets. You know, as I said, the, even the American Diabetes association didn’t even care any little bit about weight loss until drugs were available, right? Same thing with the American Heart Association. They say it’s all about energy in versus energy out. It’s like, what, cookies are the same as broccoli? You think that? Right? It’s, I don’t understand how they can be so stupid. That’s the real thing, right? It’s, it bothers me because that’s my profession.
Dr. Fung:
And I just see all this sort of really crazy, outlandish ideas that nobody ever challenges. And as my goal is to challenge some of these ideas, and now, of course, 10 years later, fasting is well accepted, that, hey, there’s lots of benefits, it’s a tool, you can use it in different ways. There’s lots of ways that you can, you know, structure it. There’s lots of ways. There’s things that can go wrong too. Like, don’t get me wrong, it’s, it’s not a cure all, but that’s, that’s where I got interested in it. Because diet turns out to be a very, very important part of health. And doctors are basically trained to give the best medicine or surgery not.
Dr. Fung:
But that’s not what being a doctor is about. Being a doctor is about making people healthier.
Bert Martinez:
Right?
Dr. Fung:
And if that means talking about the diet and weight loss, then you have to talk about the diet and weight loss.
Bert Martinez:
Well, so I have two thoughts on that. First of all, to me, I think a lot of consumers, patients are ready for the, they want the easy answer. I don’t want to lose weight. I don’t want to go to the gym. I don’t want to change my diet. Give me the pill, give me the shot. I, I think that we’re going to see gpl. It’s already exploding, or GPL one shots are exploding.
Bert Martinez:
And as with all drugs, you know you’re going to have this massive, what do you call it, situation where everybody accepts it and then as it, as it normalizes, we’re going to have a bunch of lawsuits because all drugs have some kind of side effect. And again, I’m not saying GPLs, GPL1 shots or whatever, Ozempic and all these other ones are necessarily bad, but it’s like anything else. One of the things that I love about your books that I never really perceived was a lot of what we do is based on our habits. You see a cookie and you automatically say, there’s a cookie, I must eat it. It’s what I’m conditioned to do. And it’s something, it’s like, wow, that’s so simple, but yet it’s so true. And so I’ve caught myself since reading your books, I, oh, that’s a habit. I’m just used to doing that.
Bert Martinez:
It has no value. And then the other thing that I find fascinating about the whole medical, what do you call it, world is that man, for the most part, doctors. And we think that doctors are scientists, but doctors are like a lot of like other people. You know, again, they’re, they’re conditioned. They, they put themselves in a box. And I remember years ago reading about Dr. Oliver Wendell Holmes. The, you know, he was the, the, the father of the attorney Oliver Wendell Holmes.
Bert Martinez:
But Oliver Wendell Holmes came up with this crazy idea that physicians should wash their hands in between patients visits. And he was laughed at, he was ridiculed. He was, you know, one doctor said, we’re doctors, we, we are. It’s impossible for us to make other people sick. It’s like, what? And it was like a decade later before they said, you know what, he might be right about that whole germ thing. It seems like the whole medical industry is very slow to change, very slow to accept new ideas, which I find that ridiculous because the medical profession has intelligent people in it.
Dr. Fung:
Yeah, but it’s like any other field, right? It’s, it, you have to challenge it. Right? Science is about challenging the status quo, whereas medicine actually doesn’t tolerate the challenges. That’s why it takes so long. I mean, you can look back, you can take more recent examples. Like look at the whole margarine thing, right? So margarine, of course, you know, was sold to us as healthier than butter. Okay, so butter, which people have been eating for hundreds of thousands of years, Right?
Bert Martinez:
Right, right.
Dr. Fung:
They domesticated cattle practically. So but it was no problem until the 1960s when it suddenly caused heart disease. It’s like, oh, so for 990,000 years, 99,000 years of human history, butter was fine and now it’s going to cause heart disease. Right? So instead let’s eat this newfangled fat called margarine, which turned out to have a lot of trans fats. But you remember this Bissell and all this other stuff, right? It was everywhere the heart association promoted, it turns out it was actually full of trans fats that actually caused heart disease. So not only did you not get, did you not eradicate heart disease, they actually caused an estimated hundred thousand more heart attacks per year. Like every single year we had a hundred thousand more heart attacks because we’re eating those trans fat laden margarine, right? Or you think about, you know, things like the whole low fat craze, right? So the low fat diet in the 80s and 90s where lots of bread and rice and rice cakes and snack wells and the whole thing, right? And what happened during that time? Well, obesity just exploded, right? Right. Because you’re eating a whole lot of white bread and white rice and not a lot of like, like avocados, terrible.
Dr. Fung:
Olive oil, terrible. Sardines, terrible. Until they said, hey, you know, these Mediterranean diet people, they’re actually really healthy nuts. Terrible. Why? Because they have not so much fat. Right? But that was the medical orthodoxy. So the whole thing about margarine, the low fat, the whole thing, like that’s very recent and it, it wasn’t that long ago that people, you know, really, honest to God believe this stuff about if you eat no fat, you will prevent every single heart. Like you will eradicate heart disease if you simply eat no fat.
Dr. Fung:
Of course that didn’t actually work, right? So then they had this thing called the French paradox, which was that French people were eating all this fat. They’re eating real butter, real cream, all this stuff, and they had like a third of the heart disease. Why? Because the fat wasn’t causing the heart attacks, right? They kept trying to promote it, promote it, promote it, but it actually wasn’t ever true. Right? Now of course, everybody’s gone back. So nuts are good for you, avocados are good for you, right? Olive oil is good for you. All these high fat foods are now superfoods, right? Like, oh wait, but 30 years ago you called them poison, practically, right? It’s like, what changed? It wasn’t the science. The science never changed, right? People tried to claim it was the science. There was never science behind it.
Dr. Fung:
It was just fashion. It was just that doctors, like everybody else are prone to these fashionable ideas like fat is gonna kill you, right? And then now it’s all gone back, right? Dog gone backwards. Fasting is gonna kill you. You had to eat 10 times a day. Where did that come from? Not science. It was just fashion, right? And, and this is the thing that you have to understand. You have to, you have to sort of sometimes question the wisdom a little bit. I mean, you can even look at more recent things like, you know, Covid, like we locked down kids for like years, right? Closed schools.
Dr. Fung:
Was that a good thing? Absolutely not.
Bert Martinez:
Right?
Dr. Fung:
They, they suffered quite a bit. But at the time we believed we were doing the right thing. Again, not based on science, because there was actually no data, right? Everybody tried to pretend there’s all this data. There was no data because it had never happened before. So how do you have data when this doesn’t happen before, right? And of course, you know, there now you look back and say, hey, look, you know, Europe didn’t close their schools as long, right? So their kids didn’t suffer to the extent that our kids suffered. And they didn’t die. They weren’t, the kids weren’t dying in the street, so obviously it was fine. Right? But you know, that’s how you get, you know, a whole, it’s all this group think, you know, doctors are prone to, like any other humans are prone to group things.
Dr. Fung:
So they go along with all their peers and say, oh yes, absolutely, we should lock down the children. We should lock down the children. Right.
Bert Martinez:
Well, and, and again, coming from a marketing background, the truth of, let’s say western society, or what do you call it, advanced first world society, is that if you have enough money, you can market anything. And not too long ago, cigarettes were considered. We had doctors, we had real MDs saying, oh yeah, smoking is good for you, it’s going to help your throat. And it’s like, what? I mean, you don’t have to be a doctor to know inhaling smoke cannot be good for you.
Dr. Fung:
Yeah.
Bert Martinez:
But yet for years, cigarette companies had paid doctors to say, hey, you know, smoking is beneficial this way and that way. And so to your point, we have these fads that these multi billion dollar companies get behind and they, you know, they’ll market it and until the government comes in and shuts it down, they get away with it and they hurt millions of people. And what I find fascinating also is that today most of the junk food is owned by the cigarette companies, by the tobacco industry. And so you have these highly addictive, crappy foods that literally people get addicted to because they know how to manipulate the taste and the dopamine. And it’s incredible to me, but that’s, that’s where we live.
Dr. Fung:
Yeah. And that’s the thing is that the, a lot of these things are a product of sort of our own, you know, of our own doing, right? Because it’s like people try to, like, this is the thing about the GLP1s, like Ozempic, right? They’re a band aid. They’re not the solution. The solution attacks the root cause, right? So if you have a deficiency, like suppose you have a deficiency of insulin, like type 1 diabetes, then you give insulin, and yes, that is a cure if per se, because that is, you know, it’s, you know, you’re, you’re treating the root cause, right? Or if you have vitamin B12 deficiency and you give vitamin E12, okay, great. But, but obesity is not some kind of genetic GLP1, you know, lack of GLP1 or whatever, right? That’s not what it is. And people forget that, hey, in the 60s, there was very little obesity despite widespread availability of food. It’s not like people were starving on the streets of New York City, right? People had food to eat, right? I mean, you look at sitcoms of the time, right? It’s like, you know, you see, there’s lots of people, but there’s not that much obesity. And so therefore, whatever has caused this whole problem is something that we’ve done part of our society.
Dr. Fung:
So the ultra processed foods is part of it, the habits is part of it, the marketing’s part of it. All of these things are part of it, right? How you, you get fooled into believing, you know, that you need to eat all the time and all this sort of stuff. But you know what, that’s why, you know, in my books I always talk about what’s the cause of it, right? What causes obesity? What causes this? Like, there are, you know, hormonal factors, there are emotional factors, there are social factors, right? But when you get down to it, then you can say, hey, this is what’s contribute, contributing, Therefore, let’s attack this, right? And you can use a band aid such as GLP1s, that’s fine, but it doesn’t solve the cause, right? And you can only band aid over a certain number of things, right? It’s like putting a Band aid over a bullet wound, right? It’s not going to solve your bullet wound. You’ve still got a bullet sitting inside your abdomen or whatever. Yes. You put a band aid and maybe it looks good, but it’s a band aid in the end because the minute you stop, it’s done. Like so again, I’m with you. I’m not against these drugs, but you have to recognize that they are not, they are not actually the cause, right? There’s, there’s a lot of enthusiasm about these drugs.
Dr. Fung:
Um, because I think that people, you know, people have been stuck on this whole calories in, calories out sort of thing for so long that they’ve basically thrown up their hands and they’ve given up on the diet, right? It’s like, but it always must come back to the diet. What’s, what’s changed in our diet in the last 50 years that has caused this, right? And, and, and you can, you can pinpoint different things. There’s, you know, the processing of foods, there’s the eating out. There’s, there’s, there’s a whole lot of things that have changed. So maybe we need to change them because that’s probably going to be healthier for us than just saying, everybody needs to take this drug. Right? It’s this idea, you know, you know, it’s like people like to blame the patients, blame the victims, right? Because they say, oh, people are lazy and they don’t want. That’s not true. Look at how many people like, look at the size of the market for vitamins and supplements and you know, do it self help and all this stuff.
Dr. Fung:
People want to do better when we tell people. So for example, when we tell people, check your blood pressure, people check their blood pressures, right? When we told people, you know, get mammograms, get colonoscopy, people did it because they wanted to get better, right? The problem with obesity is not that we didn’t tell people they had to exercise or lose weight or whatever is that we didn’t give them a way to do it. We focused in on the, the counting calories, right? Imagining that all calories are the same and they’re not. So, so the types of calories are important, the, when you eat and all these other things. So that’s, that’s what sort of I like to discuss in the books is, because it’s like, it’s, it’s a much more complex problem. But the more you understand about a problem, the better you are equipped to, to deal with it because, you know, more about it. Right. So you can therefore bring more rational solutions in.
Bert Martinez:
Absolutely. And so you mentioned the books, and I’ve mentioned your book. So I want to just go over it. We have the obesity code, which I think. Was this your first book?
Dr. Fung:
That was the first one, yes.
Bert Martinez:
Okay. So we have the obesity code. We have the hunger code, which I’m. I’m just now halfway through that one, and then I just finished the fasting lane, and this was the one I started with, and I. I would, you know, just tell everybody, check them out and. And see what you think. I think that. I think that once you dive into these books and.
Bert Martinez:
And if you’re not obese, you don’t have to start with the obesity code. I would definitely suggest the fasting lane. It is. It is, I think, in my opinion, revolutionary. And I say that because, just like a lot of people, I’ve counted calories, I’ve counted protein. I’ve done all this stuff, and it was always a constant. Up, down, up, down. Even though I was probably in okay shape, I was still fighting this thing.
Dr. Fung:
And
Bert Martinez:
it is amazing to me. And I think part of the problem is that, as you pointed out, doctors don’t get a lot of information or training when it comes to nutrition. But then we’ll go to a doctor who, by the way, is probably smoking overweight, and say, hey, how do I lose weight? It’s like, no, it’s not the way it works. And. And. And so I want to kind of dive into this because I think that what you’re basically saying in your books is that, again, the eat less, move more model is completely broken. And how did doctors and dietitians get it so wrong? I mean, is this. Is it just, again, we’re dumb, we’re slow, or is it just good marketing like we’ve talked about?
Dr. Fung:
It’s basically the sort of. What happens is people say, okay, there’s this energy balance equation which says body fat, which is a stored form of calories. Right? Calories is a unit of food energy. Right. So body fat’s the way your body stores calories. Right. Body fat equals calories in minus calories out. Right.
Dr. Fung:
And so the thing is that they look at this equation, they say, therefore, just eat less. Right? Fewer calories in or exercise more. And on the face of it, it seems sort of logical, but it’s actually not. Because the number of calories you expend in a day is mostly not exercise. It’s mostly metabolic rate. Metabolic rate is the number of calories that you burn with Your heart and your liver and your lungs and, you know, generating body heat and all this sort of stuff, you don’t get to choose it. So what they do is they, they pretend that it’s static, but it’s not. They pretend it’s always the same, right? So therefore, if you simply eat fewer calories, but you burn the same number of calories, then you’ll lose body fat according to this equation.
Dr. Fung:
But the problem is that your body can adjust how many calories it burns, but you don’t get to control that. Only your hormones control that. And it can go up and down, right? So if you say, I’m eating 2000 calories, burning 2000 calories, now you say, okay, I’m going to eat 1500 calories, right? There’s two ways that your body can now balance that equation. So you can either eat 1500, burn 2000, and where’s the extra 500 going to come from? Well, body fat, right? Body fat has to release those 500 calories. The other way you can balance that is that you eat 1500, your body burns 500 fewer calories, right? So you generally a little less body heat, you don’t feel as good, but you’re eating 1500, you’re burning 1500, you haven’t lost any body fat at all, even as you’ve lost, eaten less, right? And that’s the problem. When you eat a calorie of food or food energy, your body can either store it or it can burn it, right? But which one does it do, right? That’s the important question. Because if your body simply stores all those calories, then you’re going to get fat. If your body burns it all, you have lots of energy and you won’t get fat.
Dr. Fung:
So two very, very different outcomes, but you don’t get to choose which one it does. Only your hormones get to tell you why. Because hormones are the way our body runs. Our body runs on these chemical messengers that tell your body, should you store this energy or should you burn it, right? So this is the whole thing that they, they get it wrong because they think, think that if you simply eat fewer calories, that you must lose body fat. But that’s not true. In fact, virtually every scientist study says that if you simply focus on the calories, then your body may simply burn fewer calories. And that’s what happens in the most, most of the cases. And what’s the key hormone here is insulin.
Dr. Fung:
So insulin is the hormone that tells our body to store body fat. That’s its job, right? So you, if you eat 500 calories of, say you eat, you know, a sugary drink plus a donut, right? All refined carbohydrates, well, your body is going to spike your insulin way up, right? Because that’s what those junk foods do. Refined carbohydrates, it’s going to spike way up. The big spike of insulin is going to tell your body, hey, you need to store all those calories. So 500 calories goes marching into your body fat stores, right? Then the rest of your body’s like, hey, I got nothing here, right? Your heart, your liver, your lung, I got go eat something else because I need to get some energy, right? So you eat 5, 600, 800 calories of frappuccino plus donut in the morning, you’re hungry literally like 10 minutes later. Why? Because your body’s looking for more energy. Now, on the other hand, say you eat 800 calories. You have a three egg omelet with vegetables, same number of calories.
Dr. Fung:
Insulin doesn’t spike way up. So therefore, those 800 calories don’t go into your body fat. They float around for your body. Your body’s like, okay, I got plenty of energy. So you got lots of energy. You feel full because your body doesn’t need any more energy, right? Same number of calories, but two completely different results of what happened to your body, right? In the one hand, you’ve stored a lot of body fat and you’re going to go eat more food. On the other hand, you’re having stored any body fat and you actually feel good, you feel full, all that, right? What was the difference? Not the number of calories, it was the Frappuccino, which stims bite your insulin versus the eggs, which didn’t. So therefore, what’s important is to focus on what those, what those hormones are doing, right? And all that means is that some foods are more fattening than other foods.
Dr. Fung:
Well, duh, isn’t that bloody obvious?
Bert Martinez:
Isn’t it?
Dr. Fung:
Like, oh, cookies are more fattening than broccoli. Like, where’s my Nobel Prize?
Bert Martinez:
Right, right, right. And what’s so funny, what’s so funny to me is that again, I’m 60 plus years old. So back in elementary school, that was the kind of stuff that was being taught, right? Cookies are fattening, vegetables are not. Or, you know, something like that.
Dr. Fung:
But that’s what they all used to tell. Your mother used to tell you, your grandmother used to tell you, and then the scientists came in and said, no, it’s all about calories. A calorie is a calorie, right? And so all the kids now are taught no calories a calorie. So I could not eat my vegetables, not eat my meat, not eat my normal good food so that I can eat junk food. I can eat Cheetos and potato chips instead of my broccoli and eggs, and it’ll be the same, right? It won’t be the same. Your problem is you listen to the scientists who told you that a calorie is a calorie, which is plainly stupid, because again, there are measurable differences between those two types of calories, right? So the whole thing is that people get brainwashed into thinking it’s all energy balance and it’s all calories and all this sort of stuff when they’re completely ignoring the fact that different hormones tell your body to do different things. So food contains two things. One is the food energy, right? And the second thing is information.
Dr. Fung:
That food tells your body what you’re supposed to do with that food. If that food tells you you must store this all as body fat, right? You. You eat the cookies, your insulin spikes way up. Now you get the energy, the calories, but you also get the information which is the hormones to shove it all into body fat, right? It’s sort of like if you have, like, say you get a hundred dollars, right? But it immediately goes under your mattress. Now you want to go buy a hot dog on the street. Why you can’t. You have no money, right? Because it’s all stored away. Same thing.
Dr. Fung:
You take 500 calories or 800 calories, you shove them right into body fat stores. Well, you got no energy, right? You’re. You’re looking for more food coming, you know, so that you, you know, you can generate body heat and your liver needs energy, your kidneys need energy, all that sort of stuff. So it’s like, why pretend they’re the same thing? Like, this is what boggles my mind, right? It’s so obviously wrong, right? Why would you pretend that it’s right? You know, why pretend that cookies are the same as broccoli?
Bert Martinez:
And I think that there is, what do you call it? So much misinformation. And it does start with the whole count calories. Because that’s what the thing was for so many years. It’s been ingrained. You count calories and, yeah, maybe, maybe to an extent, to. You can count calories, and that might be helpful. But one of the things, again, that I’ve gotten out of reading your books is the huge Amount of, what do you call it, that, that hormones play into our, into our body composition. Right.
Bert Martinez:
And again, this makes sense because again, not to pick on, on the, on the women folk, but you know, we know that if, if that women tend to feel differently and sometimes will eat differently when they’re pregnant because they’re going through a different hormonal state or they’re having their menstrual cycle, right? They have certain cravings. And so it’s just like, wow, that makes sense. So first it’s habitual. You’re just used to eating that, right? And then second of all, it’s hormonal. But the hormonal thing I never have heard about. And I’ve been, again, I’ve been, you know, an athlete and bodybuilding and I’ve done all bunch of stuff and hormones and food were never a thing. It was always calories, protein, and, oh, you’re not losing enough fat. Well, you got to work out more.
Bert Martinez:
You gotta eat more. Right? Because by eating more you’re gonna, you’re gonna, what do you call it, Rev up your metabolism. So is there any, any scientific backing behind the revving up of the metabolism?
Dr. Fung:
Not really. I mean, there are certain foods. I mean, this, this whole idea of the proteins versus carbs versus fat, they’re. I mean, obviously they’re, they’re different Mac. They’re different nutrients, right? So they’re different macronutrients, but they have different effects. So satiety, for example. Pro. Excuse me, Protein is quite satiating, as in it makes you full.
Dr. Fung:
So you eat meat, you get quite full, right? You have a steak, it’s. It’s kind of filling, right? Versus eating brownies, which isn’t could. It’s easy to eat the same number of calories of brownie as, as steak. But one, they’re very different, right. One you feel quite full, the other one you don’t. Right. So the whole thing is that this, you know, this idea that you can, you know, change your macronutrients is, Is probably true. Right? So if you’re eating a lot more protein, that’s probably a pretty decent thing.
Dr. Fung:
Do you need to go crazy on the protein? Probably not, because you can only use a certain amount of protein. It’s different for like bodybuilders and stuff, right? Remember the days when, you know, Arnold Schwarzenegger was in his prime and stuff and you see, oh, he’s eating, he’s like eating basically chicken breast and downing like egg, you know, raw eggs. Right?
Bert Martinez:
Right. 200 grams of protein a day. Yeah. He’s an athlete. It’s the same thing with Michael Phelps. He’s. He’s, you know, they, they talk about him burning or consuming 20,000 calories a day.
Dr. Fung:
Yeah.
Bert Martinez:
And, and, but sometimes. Not always, but sometimes. I forget to mention he’s also training six hours a day. Right. And. And he’s using his entire body, so. Yeah.
Dr. Fung:
Well, the other thing they forget about is that most of that, a lot of that is not simply because he’s exercising, but a lot of it’s because he’s in water. So he’s actually cooling himself constantly, which means that forces his body to actually generate a significant amount of body heat, which is why those swimmers have to eat a lot. Right. It’s just like if you. If you’re a cyclist and you’ to cycle for eight hours a day, you can’t eat 20,000 calories. Like, you’d get fat. Right? It’s. That’s a lot of calories.
Dr. Fung:
Right? So the whole thing is that it’s. It’s also the generation of body heat for him, too. But the, but you know, the point is that, you know, a lot of this is there are differences between the types of calories, right? That protein, fats versus carbohydrates, there’s differences between process and unprocessed. But really, the hormonal issue is the most important thing, because think about it for a sec. The story we get sold is that it’s all about eat less, move more, right? And you get to control how much you eat and how much you move. So therefore, if you don’t weight, if you don’t lose weight, or if you do gain weight, well, it’s your own fault, right?
Bert Martinez:
Right.
Dr. Fung:
You decided it. And that’s completely untrue, right? Because if you think about it, let’s take women and perimenopause, for example. So we know that during perimenopause is one of the highest risk periods for weight gain. Women often gain 2, 3, 4, 5 pounds, right. And the thing is, sometimes more. And the thing is that if this is all about willpower and discipline, right? Which is the story that we all get sold. It’s about eating less, moving more. If you can’t do it, it’s discipline, willpower.
Dr. Fung:
How does every single woman in the world, at the same time in their life have less willpower or discipline and they gain weight? Well, obviously that’s a stupid thing. The difference is that they’re all undergoing this hormonal change, right? And gain weight, right? So it’s about the estrogen and progesterone, obviously, right? It’s, you know, if you take men and lower their testosterone levels and you do this sometimes for treatment of prostate cancer, for example, so you’ll, it’s, you give them drugs called anti androgens, which basically blocks testosterone. You can drop it very low. And what happens? Well, they lose muscle and gain fat. That’s what happens when you take away somebody’s testosterone, right? That’s basically what happens. Well, if it’s all about the hormones, it doesn’t matter how much willpower or discipline somebody had. You take away the testosterone, they’re going to gain fat. Or you take an example again, women, boys and girls before puberty have roughly the same amount of body fat, right? After puberty, women have more fat, about 50, more fat on their breasts, on their hips, because they’re preparing for childbearing, and boys have more muscle.
Dr. Fung:
Is it because boys have way more discipline and willpower than the girls? Absolutely not. Like, you know, I, I’ve seen teenage boys, they’re not that disciplined and they’re not that smart either.
Bert Martinez:
But, you know, and to your point, you know, we all say, man, I remember when I was a teenager, I could eat whatever I wanted and I wouldn’t gain any fat. And, and at that point in your life, your hormones are cranking, right? They’re at, they’re, they’re at the most optimal rate, right?
Dr. Fung:
It’s cranked way up. So they’re eating junk. Like, honestly, they’re eating, you know, the beer and the pizza.
Bert Martinez:
Pizza and the fried.
Dr. Fung:
Yeah, but they’re crank. They’re, they’re, they’re. Testosterone’s cranked way up, so they’re gaining muscle and losing fat. So it’s like, yeah, that’s no problem. Then of course, they get into middle age and they eat the same way, but their testosterone is not cranked as high. And all of a sudden you’re dealing with a big change. Right? But the point is that the difference was not willpower or, or discipline. The difference was the hormones, right? So if you completely ignore the hormones, you, You’ve lost, basically because you don’t understand what’s causing your body to gain or lose weight.
Dr. Fung:
And we can manipulate all of these variables, right? If you give somebody testosterone, what happens? Oh, they gain muscle, lose fat, you take away testosterone. You know, they gain fat, you give them estrogen. What happens? You give them progesterone. What happens? You give them insulin, we give them cortisol. Like, you can manipulate all of these, and we’ve done them all right, in, in medicine, and we know that those change your body weight, right? Independent of whatever you think, the willpower and discipline. Like, if I give you insulin, I don’t even care how much willpower, discipline you have, you are going to gain weight. Why? Because I just told your body through this insulin, you need to gain some weight. So you will either get hungry and eat, and if you won’t eat, your body will crank your metabolism down so low that you will gain that fat.
Dr. Fung:
Why? Because I told your body to gain that fat. Right? And that’s the way it works. That’s real life, right? So if, therefore, if insulin is one of your major determinants of how much fat you’re going to gain, because that’s the signal, right? Gain fat or lose fat, Right? That’s your signal. Then if you don’t pay attention to it and think that you can eat all these brownies that spike your insulin instead of the broccoli and eggs, which don’t, well, you’re going to be completely messed up because you’re going to say, hey, I counted my calories. I got rid of all my eggs and vegetables so I could eat ice cream and pizza, right? And why. So why am I gaining weight? Because I cut 500 calories, but I’m eating, you know, french fries and, and, and, and, and potato chips, right? It’s like, yeah, that’s your problem right there. You’re spiking insulin. You’re telling your body to gain fat.
Dr. Fung:
So understanding this is truly, is really important because if you understand that some foods are more fattening than other foods, foods, then you can make that decision. Right? But if you think it’s just about the calories, you can’t. Right? So I can eat, you know, broccoli all day long, but who gets fat eating broccoli? Like, probably zero people in history, Right? It simply doesn’t happen. Right, right. Can’t do it. So it’s like, okay, but why would you simply say that it’s the same? Why are those calories from broccoli now considered the same as cookie calories? Right? Because they’re different. So the whole point is that if you understand what’s.
Bert Martinez:
Hey, thanks so much for watching. If you would please spank that like button. Leave a comment, or just hit the like button, I would appreciate that it tells the YouTube algorithm that you appreciated the content and it helps us out a lot. So please, like, subscribe or just leave a comment. Thank you so much.
Dr. Fung:
What’s happening in your body, then you can make Better decisions for your body, right? And it’s all common sense stuff, right? It’s not like stuff that’s, you know, gonna tell you something crazy. It’s gonna tell you exactly what your grandmother told you, right? If you want to lose weight, stop eating all that junk food. Stop eating the refined food, stop eating the starchy foods, eat your vegetables, eat your meats, right? And you can find that advice from, from a hundred years ago. There’s, there’s, there’s books. Reader’s digest in the 1920s had exactly this, right? You want to lose weight, don’t eat the bread and the rice and the potatoes. Eat as much meat as you want. Eat as much green vegetables as you want.
Bert Martinez:
Hey, that’s, let me ask you this, and I want to talk about fasting here in a little bit because is, again, fasting is one of those things that’s been around what, a thousand, two thousand years, and, and nobody’s died from fasting. I mean, obviously there’s a difference. I want to make this very clear. There’s a difference between starvation and fasting. And fasting has not only been used for health reasons, but it’s also been used for religious reasons and, and all sorts of different things. But you know, again, you, you put out these three books and, and, and you, you’ve had this, I don’t know, this, you changed your, your focus from kidneys to weight loss and fasting and things of that nature. Have you gotten a lot of flack from your medical community?
Dr. Fung:
It’s interesting because of course there’s a lot of sort of pushback initially. Now there’s a lot of people who sort of have come around to thinking about it, but it’s a lot slower than you would think. Like, if you read stuff today even, they still talk about, oh, how fasting is so dangerous to you. It’s like, oh my God, like there was something, I think two years ago or something, they had something, they said, oh, if you fast, this is, we’re talking 16 hour fast a day, right? Your, your risk of a heart attack might go up by like, you know, a hundred percent. So it’s like, okay, well, first of all, like, you know, they mentioned fasting in like the Bible. Right, right, right. Every single year, right. Around Lent, my priest talks about fasting.
Dr. Fung:
Yeah, every single year, Right. Because it’s in the Bible. Right. And so it’s been around at a minimum for 20, 26 years. Right. So people have been doing it for 2000, 26 years, minimum, without any problems. And now of Course it’s a problem. Why? Why would you.
Dr. Fung:
If people have been doing it for 2,000plus years with no problem, no medical oversight, no nothing, right? It’s a priest that’s talking about fasting, not a doctor. It’s not. And he’s talking to everybody, every single person in that congregation, right? It’s not like, oh, I’m going to give you personalized medical advice. It’s like, no, you should fast. And it’s like, it’s a priest that’s telling thousands of people. It’s like, okay, so how is this so dangerous to you? Like, really? So you think about fasting, which is, remember, it’s different from starvation. Starvation is not voluntary, right? So when you’re starving, you want to eat, but there’s nothing to eat. When you’re fast, there is food to eat.
Dr. Fung:
You choose to not eat it, which is hugely important. Because if you are doing badly for whatever reason, you don’t feel well or whatever, you can break it at any point, right? Because food is available to you. Right? And that’s the key. It’s. It’s a voluntary decision. But the other thing is that what happens during fasting, well, what’s going to happen is that your body is going to use the calories that it’s stored. So if you have body fat, then you can fast. That’s it.
Dr. Fung:
That’s all there is to it, right? I don’t get why people get so bent out of shape about it. Because it’s like, why do you think your body stored all those calories in the first place? Right? It’s just like putting a lot of food in your fridge and deciding that, hey, you know, now that I have no food, I’m going to go die. Just get the food from your fridge. Your body carries all these calories. Now you’re not eating. What do you think is going to happen? Your body’s going to use some of the calories. That’s good, because a lot of people, they’re obese, they get sick from it, right? They’re carrying too many of those body fat. They’re getting type 2 diabetes.
Dr. Fung:
Your body’s going to burn some of the sugar, which will make your diabetes better, or it will burn some of the fat, which will make your obesity better. That’s it. That’s all that happens. When you don’t eat, your insulin falls, which is the signal to your body to release the calories from your body fat, Right? Which is no different than, you know, you have a fridge that’s so Full of food that you can’t even shut it. And you decide not to go to Costco that day. So good, open up your fridge and eat something. That’s all. What’s wrong with that? And people are like, no, you must go to Costco three times a day.
Dr. Fung:
It’s like, why? I don’t get it. Is it fun? No, not necessarily. Right? It’s not necessarily fun to fast, but it is something that is healthy, right? And it’s not simply healthy, but it’s withstood the whole test of time, as in, in 2000 years. Like, you know, it’s not like I work in the hospital all the time, right? It’s not like around Lent when people are being told to fast by their priests, that we see all these people in the emergency room and eat for like a day. It’s like, come on, the whole thing is ridiculous, right? It’s like, and all these doctors are so slow to really come around to this idea that this is actually something that could be potentially therapeutic. That is if you have too much body fat that is making, giving you health problems, then fasting is a realistic option to get rid of some of the body fat. Right? So it’s like as in if you take Ozempic and don’t eat, that’s good. But if you don’t eat without the Ozempic, that’s bad.
Dr. Fung:
What are you talking about? Like, I just don’t understand these doctors.
Bert Martinez:
But I think it goes back to again, this, this weird thing that if a doctor, because doctors know everything and, and, and they’re omnipotent and, and so if a doctor says, here, take this diet pill or, or this, what do you call it? Because there’s been several of them out there, but you take the shot or this pill and therefore you’re not going to eat as much, that is okay, because it’s, I’m a doctor, I’m telling you this. But if you do it on your own, well, wait a minute. That could be dangerous.
Dr. Fung:
I just think that’s ridiculous.
Bert Martinez:
But that’s the world we live in, right?
Dr. Fung:
I mean, that is the world we live in.
Bert Martinez:
You know, one of the things, by the way, and I again, this is, this is an outstanding book. And, and so I can’t remember which one it was. I don’t know if it was Megan Ramos or Eve Meyer Mayer, but one of your co writers here was, had not one, not two, but I think three different gastric type bypass or gastric surgeries. And she’s still obese.
Dr. Fung:
Yeah.
Bert Martinez:
And And I’ve known so many people. Again, I’m being exaggerated. I’ve known a few people that have had gastric surgeries and they’ll lose weight for a short time. In fact, some of them, I think, lose so much weight so fast, they have that hanging skin.
Dr. Fung:
Yeah.
Bert Martinez:
But then they all gain it back.
Dr. Fung:
Yeah. Because the problem is they didn’t. They never understood the problem, which is that when you restrict the calories, then if you think about it, you, you restrict the calories, calories goes down, but your hunger goes up. So eventually what happens, and this is what the hunger code is about, is I’m trying to understand hunger as a problem. And it’s odd that nobody ever talks about it, Right. Because that actually is the crux of the problem, Right. If you’re saying your problem is overeating, your problem is actually over hunger. Because if you aren’t hungry, you wouldn’t eat, right? We eat when we’re hungry.
Dr. Fung:
We don’t eat because we’re full, Right?
Bert Martinez:
So let me ask you this, because I think, I think you’re right. And I think that is based on nutritionally sound eating. Like you mentioned eating a steak or, you know, fatty fish or something like that’s going to really fill you up as opposed to if you’re eating a bunch of brownies, you’re gonna, you’re gonna have to eat a lot of brownies, I mean, to try to get there. Because your, your body’s going through all these hormonal changes. Because I’ve seen people who have just ate, have eaten a, a really crappy meal, and they will continue to eat and eat and eat. It’s like, dude. And then of course, they are obese because they have all of the stored fat. Because they’re overeating.
Dr. Fung:
Well, because the, the, the difference is, and this is the problem with ultra processed foods really, is that you eat but you don’t get full. Why? Because it’s not calories, right? And this is the thing. If you ate a lot of steak and vegetables and real food, right? You’re gonna get full. So then you’re gonna want to stop, right? So you go to a buffet, you eat, you’re full. Somebody says, here, have this pork chop, or we’re gonna get charged. And you’re like, oh, I can’t do that. Right? But then somebody says, hey, have a cookie. You’re like, oh, sure, right? It’s like, why? Because the cookie, because of the way it’s processed, actually has no satiety value, Right? You’re not getting more full.
Dr. Fung:
So therefore you can eat it, right? So as kids we used to say, oh, I have a second stomach for dessert, right? Because you could actually eat dessert after a full meal because it actually doesn’t create any satiety signaling, right? Just like if you’re to eat, if you’re to drink like a soda, Big Gulp soda, right? A huge thing of Coca Cola or whatever. You could drink 5, 600 calories, but you don’t feel any more full than you did before that, right? You could drink water and you feel the same satiety level, right? And that’s the thing. It’s the hormones that tell you whether you should eat or not eat or you should be full or you should be hungry, right? So that’s the real problem. So with gastric bypass surgery, you can physically restrict the calories, right? Calories goes down, but the hunger keeps going up. And then people eventually find their way around that, that restriction that you put on. They’ll drink, you know, smoothies and eat ice cream and stuff that they can get down and then they’ll regain all that weight. That’s why nobody even talks about weight loss surgery anymore, right? Because it was so unsuccessful. We thought it would change the whole world and it didn’t.
Dr. Fung:
In the end, it wasn’t the real problem. Real problem was the hunger, which is what the hunger code is about. So then now you get to a drug that, that really works on hunger. 1. One pathway of hunger, right? I talk about all the different pathways of hunger. And the thing is that you can manipulate this one system, this GLP1 system and, and create, you know, get rid of the hunger. And therefore that gives you longer lasting weight loss. The problem is there’s a lot of pro, there’s a lot of side effects and other, there’s other issues because it’s a drug, right? But, but you know, for sure, you know, trying to get to that hunger is the problem.
Dr. Fung:
And, and I think that it actually goes further than just the hormones. I think a lot of it comes back to emotional hunger and also the social hunger, the conditioned hunger, which is actually, I think the real problem of, of where we are today is really the ultra processed foods which are creating a lot of the food addictions and so on. But it’s a complex problem and I think that we do ourselves a disservice by trying to dumb it down to a single thing such as calories, which is not even the best thing to focus on. And then, you know, and the sad part is that we, we dumb it down to calories. Calories, calories. A calorie is a calorie. All calories are the same, right? And then when people fail, we say, hey, it’s your fault. You failed.
Dr. Fung:
Right? We give them this really, really bad advice, right? Oh, yeah, you can have ice cream for dinner because it’s the same number of calories, right? Yeah, sure, go ahead. Right. Meanwhile, they’re, like, starving. They’re so hungry because they ate ice cream for dinner instead of a steak and eggs, they had ice cream. They’re so hungry. And then they can’t help themselves when they do go get something else. And then the people go, oh, look, you lost willpower. No, the problem is you didn’t focus on the hunger, right? You focused on the calories and not the hunger.
Dr. Fung:
It was the wrong thing to look at. And then we blame them for it. We say, look, you should not.
Bert Martinez:
Not only do we blame them, but we blame ourselves. I wasn’t strong enough. I, I, I failed myself. I, you know, and, and I think, especially again, females are really prone to this abusive, chronic way of beating themselves up. Right? I gotta, I gotta get ready for swimsuit season. And, and they really just go through so many changes, and they have, I think, this kind of abusive way of talking to themselves that they would not allow anybody else to talk to them that way, and they certainly wouldn’t talk to their children that way. But they beat themselves up because they can’t get over it. And as you point out, it’s.
Bert Martinez:
It’s, in one sense, it’s fairly simple. You have to deal with the underlying root, which is hunger. And sometimes, as you’ve already pointed out, sometimes it could be some emotional stuff there. But bottom line is you have to figure out that hunger code, and it makes it simple.
Dr. Fung:
Yeah, yeah, I think so. I think so. And that’s the, that’s the real tragedy of the whole situation that we’re in right now, is that we fail ourselves for so long. We think the answer lies in a drug as opposed to understanding the disease, Right? So we misunderstood the disease. We said, it’s all calories, calories, calories. When that was a complete failure, we said, oh, the solution is actually this drug. It’s like, okay, I think we’re missing a few steps here, but, okay, and, and, you know, I think that’s where I like to try and bring it back to. Hey, let’s, let’s try to understand this.
Dr. Fung:
This, the, the problem, right? Which is hormones. And in the hunger code, I list like 14, 13 or 14 different hormones that affect weight, right? And again, not controversial. We know that they do affect weight. Weight, right. It’s, it’s absolutely true. So if, for instance, insulin affects weight, which we know it does, then the foods you eat influences the insulin, which influences the weight. So therefore those, those choices matter, right? So the whole, the whole thing is that I think that we have to sort of understand the issues. We have to, you know, understand what’s happening so that we can, we can do something about it.
Dr. Fung:
There’s, there’s lots of data on habits. There’s lots of stuff about ultra processed foods, food addictions, you know, how, how your micro environment, that is your friends and family, actually influences your way to a huge degree. We see this all the time, right? It’s it, because we’re human, right? If, if everybody around us is eating french fries, we’re eating french fries. If everybody around us is eating, you know, chia seed pudding, we’re eating chia seed pudding, right? It’s, it’s just the way life is, right? It’s, you know, it’s, again, to deny it is simply, is simply, you know, irrational. Like, you gotta acknowledge that these are the social aspect of that is, is what makes us human. So we have to take into account, and that’s why you take somebody, a Japanese person in Japan, and their risk of obesity is very low. You plunk them down in San Francisco and all of a sudden their risk of obesity just skyrockets. They take an Italian in Italy, very low risk of obesity.
Dr. Fung:
You stick them in New York City, rate of obesity just skyrockets. Why? It’s the same Italian guy, same culture, but the food environment is completely different. Social habits are completely different. Everything is different. Right? But it wasn’t the person, it was the environment. Right? And that’s the whole point. It’s like we have to look at the environment in, in which we live because we can make those changes to our environment to a certain degree, right? And that’s where certain habits like fasting and stuff can be very, very beneficial, right? And it creates sort of good practices that help you stay at a certain weight and stuff. So, yeah, there’s, there’s, there’s so much, I think that these books go into about all of those things.
Dr. Fung:
And honestly, I, I, I, I would guess that most people, most doctors have never learned about it. There’s so many doctors have come up to me and say, wow, I didn’t know any of this. It’s like, neither did I to learn it all myself.
Bert Martinez:
All right? So I want To, I do want to. Before we dive a little bit deeper into fasting, I do want to ask you about dieting and, and metabolism. So does dieting slow down your metabolism? Is that what you were referring to? When, when, you know, I guess not controlling the hunger and, and, and stuff like that. So metabolism and dieting are not good bedfellows.
Dr. Fung:
Yeah, it, it really depends on the hormones. So if you eat, if you simply focus on the calories and this was the classic sort of low fat diet, right? So what happens is that if you simply cut the fat out and you eating all carbs, right, that’s the fastest way to cut calories because fat is very calorically dense. So if you cut all the fat out, you’re eating a lot of rice cakes and you know, white bread. The problem with that is that you’re, you’re, you know, you’re spiking your insulin. Your body wants to gain that weight. And in order to gain that weight, because you’re not eating a lot of calories, it has to reduce the number of calories. So what happens is that as you lose weight, the number of calories you burns goes down and down and down. So I’ve seen people who are, who have a total caloric expenditure in a day of like 800 calories, like that’s all they can eat.
Dr. Fung:
If they eat a thousand calories a day, which is very little, they’ll gain weight because their body’s only burning 800. That’s a problem when you have, it’s not the yo yo dieting per se, but it’s when you sort of, when you sort of bring everything down. You know, it’s the hormones, right? It’s, it’s all about the insulin. If you’re storing all that, those calories and you’re, you’re telling your body to gain the fat. One of the ways your body does that is by ratcheting down the metabolic rate. So that’s the whole, that’s the whole point. So yes, dieting can, but if you do it right, then no it won’t because you’re not allowing your body to store the calories. Right? So it really depends on the type of, of calories, right.
Dr. Fung:
You, you hear of people who are eating, you know, 3,000, 4,000 calories and not gaining any weight or even losing weight, right? People, People, you know, it’s like, because it’s the type of calories, right? There’s good calories and there’s bad calories, basically.
Bert Martinez:
Yeah, I think that is something that’s so misunderstood. But at the same time it’s, it’s one of those things that at one point we understood in elementary school that calories are not the same. And, and we also, again, growing up, I always heard about having a balanced meal and, and, and you know, you had your protein, you had your, your vegetables, then you had some starch. And then somehow again, through I think marketing more than medicine, you know, we got to the point where these ultra processed foods became a thing. And I think that is when everything started going badly. Because, you know, when we talk about the low fat or no fat fad that we, that we’ve gone through, a lot of scientists now are saying, hey, all of that low fat, no fat is now causing the dementia epidemic that we’re having. There’s some kind of connection between the, the fats that we need for our brain health and, and the fact that we didn’t, you know, that we cut that out for so long is, is, is, you know, behind this dementia stuff at least one of the factors. So I think that again, it’s just, it’s crazy to me, but it’s unfortunate that that in, that’s the world we live in.
Dr. Fung:
Yeah, I mean, I think that’s the real, the real thing is to sort of try to understand what, you know, I’m not trying to reinvent the wheel, right. All we need to do is go back to like the 1960s and 1970s. Right. So if you think about it, right, you’re eating real foods, you’re not snacking all the time. Right. Remember, you know, the, the, the, you wanted a snack after school. No, you’re gonna ruin your dinner, right? You wanted to snack after dinner. No, you should ate more at dinner.
Dr. Fung:
Right? That’s the way it was. Now, of course, it’s like, oh, you should snack all the time.
Bert Martinez:
Right.
Dr. Fung:
You know what?
Bert Martinez:
And I think that one of the reasons that snacking again back in the day would ruin your dinner is because you were snacking on real foods.
Dr. Fung:
Yeah.
Bert Martinez:
Maybe you weren’t snacking on, you know, on, on these ultra processed foods that go through your system like that. And so today you and I could sit down and we could have a really crappy snack and we’re so ready to eat an hour later.
Dr. Fung:
Yeah, yeah, but the, the, the, the key is that like you’re having real food, you’re having a regular fasting period right after dinner to breakfast. So say you ate dinner at like 6 or 30 or something, right. And you have breakfast at like 8:30. Well, that’s 14 hours of fasting that you do every single day without even considering it. Fasting, right, but it was, that’s why you call it breakfast break fast. But the point is that like if you think about, you know, 14 hours a day, sort of baseline, right? I mean, people now eat all the time. They eat basically from the minute they get up to the minute they go to sleep. They did a study a few years ago where they just asked people to track when they eat and it was like, you know, the, the average period of eating was like 14 and a half hours or something like that, right? So it’s like they didn’t, people basically didn’t stop until, you know, they went to bed, right? So it’s like where, where’s your fasting period? Right? So the point is that like, look, in the 60s and 70s, there was a period of time that you ate.
Dr. Fung:
That’s when your body’s going to store calories. There’s a period of time you don’t eat and that’s a period of time you’re going to burn those calories, okay? So now you keep those imbalance. No snacks, right? Eat real meals at the table, like not running around doing whatever, right? No ultra processed foods. And hey, obesity just not a problem. Now of course it’s like, yeah, we have all these habits. Oh yes. Nah. Oh yeah, sure.
Dr. Fung:
Eat ultra processed foods because a calorie is a calorie, right? And it’s like, okay, we have all these, these things that are sort of counter to what we did in the 60s and 70s. And then the only way we can actually deal with the consequences to take Ozempic, like, yeah, why don’t you just go back to the way you used to eat, right? Hey, it wasn’t that big a problem. Like there’s no change physiologically or genetically. Like the human genome has not changed in that 50 years for the same humans that we were. If you just ate real food but left yourself an adequate fasting period, hey, you might do all right. And once in a while you have a longer fast, right? It’s like once in a while you’re going to have, once in a while you’re going to have a feasting period, right? Christmas or celebrations. And once in a while you’re going to have a fasting period, Lent or whatever. So that’s going to balance yourself, right? It’s like, oh, well that makes sense, right? Keep yourself feasting, you’re feeding, which is storing calories and you’re fasting in balance.
Dr. Fung:
That’s all you need to do. Now, of course we’re like, oh, you should eat all the time. Fasting is bad for you. And hey, the calories, calories. So eating cookies and eating broccoli is the same. And then it’s like, hey, why are you getting fat again? It’s like, because you’re eating all the time and you’re eating cookies when you should have been eating broccoli. Well, duh, right? It’s like, it’s crazy.
Bert Martinez:
All right, so life in the fasting lane. And I’m going to put links in all the show notes for your books. But let’s talk about intermittent fasting. You know, from reading the book you mentioned, you know, 16, 8 is a pretty common fasting eating period. So you’re going to fast for 16 hours and then you have a window of eight to, to feed on. And then in the book you also talk about, you know, like a two day fast, a three day fast, things of that nature. So start me off. If I’m a beginner, I’m gonna go crazy and try this fasting idea.
Bert Martinez:
Where should I start?
Dr. Fung:
Well, you can start with again 12 to 14 hours. So that’s just the normal period of fasting. What used to be not even called fast. Right?
Bert Martinez:
Right.
Dr. Fung:
14 hours is sort of a baseline. Right. That’s the period of time that you’re going to not make sure you don’t eat so that your body can, you know, burn off what you took in the day. It’s not going to do a lot for your weight loss because it’s just balance. So then you can push it a little bit. So 14 hours, you can push it up to 16 hours. And some people are strange because they think, oh, 16 hours are going to drop all this weight. No, you only push it up by a very little bit.
Dr. Fung:
You can’t expect miracles just because you didn’t eat for that extra hour and a half. Right? So you can do that. Some people do very well with it, which is great. So there’s two things that you have to focus on. One is the types of food you’re eating. And then the two is the fasting period, which is when you’re eating. So therefore what you need to do is if you’re focusing on the foods, that’s your diet. It has nothing to do with the fasting period, but your diet focus on real foods.
Dr. Fung:
Get rid of the ultra processed foods, get rid of this, particularly the ultra processed carbohydrates, because carbohydrates stimulate a lot of insulin. Then you focus on the fasting period, which is where you’re going to allow that fasting, the, the, the, the insulin to fall that year. So you’re going to release those calories. So you can go 16 hours or you could go longer. If you want to lose weight, you need to go longer, right? You’re just giving your body a chance to use those calories, right? So you got to go to 20, 25, 4 hours, which is a one meal a day schedule. You don’t have to do it every day. You could do it like three times a week, for example, or you could do it over a day. You could do two days, you could do three days, right? There’s no rights or wrong.
Dr. Fung:
Some people like the longer ones, some people like the shorter one. So if you prefer to do the longer ones, you can do them less often. If you do the shorter ones, you generally have to do them more often. But which one is right for you is really up to you, right? The, the longer ones tend to, to be more powerful, but they’re harder because they really start to interfere with your life, right? Because if you have dinner plans or you’re going out with colleagues or going for a drink with everybody and you’re not eating, it, it’s, it’s a little awkward, right? Not totally awkward, but a little awkward. So it starts to interfere with the social side of things. Whereas the shorter ones are much easier just to slot in wherever. But you can use both of them. You can use them wherever.
Dr. Fung:
It’s completely flexible. So you can use them when you want them, you can not use them when you want them. So there’s lots and lots of different options. You can stop for a while. If you’re going on vacation and you’re going to want to like, you go to Italy, you want to eat some Italian food, right? So it’s like, okay, well, maybe you’re not fasting much for that week, but you maybe do more the next week after you get home, right? So there’s lots of variations, lots of flexibility, but the principles are sort of the same, right? Make sure you’re eating good foods. Make sure you’re leaving lots of time for your body to, to, to, to use it up. Dealing with the hunger, you do have to know about because you will get hungry. I mean that if you’re used to eating all the time and you don’t eat, you will get hungry, right? And that’s not just the physical hunger, but the emotional hunger too.
Dr. Fung:
That, right? I really want to eat that. That’s actually a lot harder to deal with than the physical hunger. Physical hunger is actually easy to deal with. It’s the hedonic hunger, which is that sort of emotional. Like if you don’t eat for a while and then you see a, you know, slice of pizza or something, you’re like, wow, you know, I really want that. Right. And that’s actually the hardest thing to deal with. So that’s where you can make some changes.
Dr. Fung:
So you can. You can change the fast slightly so that you don’t do a full fast. You might do like a very, you know, allow a little bit of, say, food once a day, like a little bit of vegetables or something like that, just so you take the edge off that. And it’s not the physical hunger. It’s that sort of emotional sort of hunger. And a lot of the research says that when you’re going multiple days, taking a little bit on those days is not that big a deal. You preserve most of the benefits of the past.
Bert Martinez:
All right, so what are some of the benefits of the fast? I mean, we’ve talked about the fact that by fasting you’re starting to use the stored energy or the stored calories, your fats. What are some of the other benefits of fasting?
Dr. Fung:
Yeah, so really there the. The main things that people think about is the weight loss. So your body will store fat calories, which is energy in two ways. Glucose, so. And sugar. If you have too much sugar, you have diabetes, or fat. If you have too much fat, you have obesity. Right.
Dr. Fung:
So as you don’t eat, as you fast, your body is going to burn off some sugar, which means it’s going to be very good for diabetes or it’s going to burn off fat, which is very good for obesity. So weight loss and type 2 diabetes are main things. And the thing that’s important is that if you reduce weight or if you get rid of diabetes, your risk of other diseases goes way down, because those are very high. Those conditions put you at high risk of heart disease and strokes and cancers and, you know, eye disease and kidney disease and infections and all kinds of things. So getting rid of those, getting those two down is actually hugely important. But above that, you can also get things like it decreases inflammation, it helps with cellular rejuvenation and all these other sort of ancillary benefits. And some people do them for those reasons, longevity particularly. So there’s.
Dr. Fung:
There’s lots of different sort of things to highlight. But, you know, the main two are going to be weight loss and type 2 diabetes, which will influence your risk of other Diseases, because, you know, heart disease, strokes, kidney disease, you know, those are really, really bad things. But even if you don’t have those, you know, you might, you might feel better. You have less bloating, you have less inflammation, sometimes helps with the pain, sometimes helps with wound healing. So there’s lots of other things that go on during fasting that might be very highly beneficial. You get these big peaks in growth hormone goes up, for example. So that might be very good. You know, so there’s, there’s, there’s lots of things that, that, that go on that, that might be useful for people.
Dr. Fung:
I love that.
Bert Martinez:
And one of the things that you talked about, this cell re. Rejuvenation, I think it’s also called autophagy or something like that. Right. And, and talk a little bit more about that. Why is that critical?
Dr. Fung:
Autophagy is basically a process where your body gets rid of these sort of old subcellular parts and sounds really bad. People say, oh, you’re getting rid of this stuff, but that’s actually good for you because you’re getting rid of the old stuff and then you’re going to rebuild a lot of new stuff. And that’s the process called autophagy, which is relatively recent. The 2016 Nobel Prize in medicine was awarded to one of the key researchers in autophagy. So it’s only been about 10 years that people have been talking about it. But again, you know, if, if you’re talking about, you know, getting rid of old cells and then getting new cells or cell your parts, that’s, that’s rejuvenation, right? You’re getting rid of the old, bringing in the new, and then you’re going to feel better. So a lot of people who do the fasting do find that they, they, they just feel better about themselves. Right.
Dr. Fung:
So, you know, you know, for a lot of different reasons. And that’s why in the past, fasting was always considered something highly beneficial. Right. It was called a cleanse or detox or whatever they called it.
Bert Martinez:
Right.
Dr. Fung:
Until about, you know, 40 years ago, fasting was like, good for you, right? Oh, you should fast more. Right. And you heard that at, you know, religious services all the time. Oh, prayers and fasting and almost for the poor. Right. So the, the, you know, it was always in a positive connotation. Right. And this is traditional, right.
Dr. Fung:
It’s, it’s, it’s been passed through throughout time as something that’s actually really, really good for you. You’re not doing it because it’s fun. You’re doing it because it’s good for you, right until the last little while. And all of a sudden, without science, I should add, the people just decided, hey, it’s no good for you, you should never do it. It’s the worst thing you could ever do. Okay, I don’t understand where you got that.
Bert Martinez:
Same place they got the, the doctors can’t make other people sick. You don’t need to wash your hands. That same book, I think. You know, so this is something that I’ve noticed since I started doing the, the fasting is when I consume, let’s say a highly processed food or something that’s really starchy, I can feel it almost instantly. And for me specifically, like if I consume something that is ultra process, I can immediately feel my hunger go up. It’s a, it’s almost an instant thing. And again, to you mentioned being, we call it kind of balancing things out. So my wife and I about talked, took a little vacation not too long ago.
Bert Martinez:
And while on vacation, I ate a lot of crappy food. But I was aware, you know, I basically scheduled eating crappy food because that’s just going to be part of the thing. We’re out there with friends. And what I noticed from all the crappy food that I was eating, and I had never noticed this before, is the next day I’m sluggish and not to gross anybody out, I’m gassy.
Dr. Fung:
Yeah, no, no, no, it’s true, it’s true. And, and I think that, you know, when you get rid of it, you realize that it’s, you know, that, that it does play a role. Right. Because it’s not that good for you. And it, I’m not saying that you should never eat crappy food. I mean, sometimes it’s, it’s, it’s, it’s
Bert Martinez:
part of the fun sometimes. Right. It’s just, yeah.
Dr. Fung:
It’s part of life. And sometimes you want it. Right. It’s like, that’s okay as long as your mind feels, you understand that, hey, you know, I realize that this is crappy food. I’m going to do it anyway for this reason. Right. But it’s not gonna like, this is not just the normal. Right, Right.
Dr. Fung:
So you want to be aware of it.
Bert Martinez:
Right.
Dr. Fung:
Being mindful. And I talk about mindfulness in the hunger code is, is not about necessarily doing the right thing. It’s just knowing why you’re doing what you’re doing. Right. So that if you, you understand, hey, I’m doing this because I’m really, you know, in this situation that’s okay. Because you’re not always going to be in that situation. Right. And the next time you’re not in that situation where you’re faced with the crappy food again, you’ll say, oh, I don’t need that.
Dr. Fung:
Because, you know, I, I understand. I only did that because I was in that situation. I was in that state of mind and that’s why I did it this time. And it’s totally different. I don’t need this crappy food. I’m gonna go and have this instead, which is going to make me healthier or better.
Bert Martinez:
Yeah, absolutely. And, and I like what you’re talking about, that mindfulness or that intention Alness being intent makes a big difference because, you know, hey, I’m going to be out with my friends, I’m going to have a few drinks or I’m going to eat some again, crappy food. Then, then I need to balance that out. And I think one of the, the big disservices that that has happened to again, first world countries is starting our children off with these ultra processed foods, meaning cereals. Right. And, and what is shocking to me is you look at these crappy cereals and they all say the same thing, is that, hey, it’s a, a healthy way to start the, start your day. And it’s like Frosted Flakes. It’s just pure sugar.
Bert Martinez:
It’s like, how is this, how is this a healthy way to start your day? It’s like, again, you don’t have to be a doctor, but common sense telling you starting your day with a bunch of sugar can’t be good.
Dr. Fung:
Can’t be good. Absolutely. So, yeah, it’s all just marketing prowess. Right. So that’s, that’s really all it was. Sorry, I, I actually have to go soon because I have.
Bert Martinez:
Sure. No, let’s wrap it up. If, you know, if you were going to kind of boil down what we’ve talked about today, what, what should our listeners, viewers understand about our conversation today?
Dr. Fung:
I think the, the key points would be one, you know, cutting out ultra processed foods is really important because it’s not just about the calories, it’s about the whole quality of those calories. Right. Number two is make sure you have an adequate fasting period, which is the sort of making that, that’s that balance. Right. And number three is making sure that you redesign your sort of physical and social environment because we’re all social creatures to maximize your success. Right. So if you are in with a group, in a situation where you’re always going to be eating Poor, you know, making poor choices, then you want to get out of that situation or redesign that situation. Right? And that’s the three sort of golden rules of weight loss that I talk about in the Hunger Coat.
Dr. Fung:
But, you know, the books really are sort of a deep dive into the science of sort of why we gain weight, and so therefore, how you can more successfully lose that weight.
Bert Martinez:
Dr. Fung, thank you so much for stopping by. Looking forward to having you back again.
Dr. Fung:
Thanks so much.
