The Psychology of Hunger | Dr Jason Fung

Jason Fung (0:00)

Why do people get fat? Because we've been sold this idea that it's just math, calories in, calories out, but it's completely untrue.

Michael Gervais (0:08)

Why do diets often fail? It's not because people lack discipline, but because they're fighting their own biology.

Jason Fung (0:14)

People were saying that type 2 diabetes was a chronic and progressive disease, and there's nothing you could do about it but take your drugs. It's a big lie, because every doctor knew that if you lost weight, your diabetes would either get better or go away.

Michael Gervais (0:28)

Welcome back or welcome to the Finding Mastery Podcast. I'm your host, Dr. Michael Gervais.

Jason Fung (0:33)

A high-performance psychologist named Michael Gervais.

Michael Gervais (0:36)

Who Pete Carroll brought in to work with the Seahawks. Famous for his work with Felix Baumgartner when he jumped out of space in the Stratos Project.

SPEAKER_3 (0:43)

Olympic athletes depend on something more than just training and talent. They have to stay mentally tough.

Michael Gervais (0:49)

Today, I am stoked to sit down with Dr. Jason Fung, physician, nephrologist, and one of the leading voices reshaping How We Understand Metabolism, Obesity, and Chronic Disease. He is the author of several influential books including The Obesity Code, The Diabetes Code, and his latest book The Hunger Code.

Jason Fung (1:06)

When you say, okay, why is somebody gaining weight? The answer is because you're hungry. So why are you hungry? And there's actually at least three different types of hunger. I mean, you know, psychology is actually a hugely important part of what drives behavior.

Michael Gervais (1:20)

100%. If you have a heart issue, you're going to want to pay attention. If you want to lose weight, then definitely pay attention.

Jason Fung (1:25)

But if you look at overweight and obese, it's somewhere around 70% of the American adults. Other countries are often like 30% and 40%, right? The question is why? It's not the person, it's not the culture.

Michael Gervais (1:37)

And if you have type 2 diabetes or you're on the path to it, you are going to love this conversation.

Jason Fung (1:43)

I think if you're really struggling with the weight loss, the main thing I would say is that...

Michael Gervais (1:49)

With that, let's jump into this week's conversation with Dr Jason Fung. Jason, I'm really excited to sit down with you because you've got your arms around something that is really important for all of us. And so, can you first talk about your background just a little bit to set the stage? And then I'm gonna want to transition into why the current study and why the current book that you've written.

Jason Fung (2:18)

Sure, so I'm a specialist physician. So I trained in kidney disease and sort of seems a little bit out of the sort of weight loss thing, but there's actually a rhythm to it. So what happened is that I treat kidney disease and for many, many years I just sort of treated it conventionally like everybody else, but as you know, we've had its real obesity epidemic really starting since the late 70s and that translated into an epidemic of type 2 diabetes and that sort of pushed the numbers up and the number one cause of kidney disease is actually type 2 diabetes. So as I'm practicing, what we're seeing is just more and more type 2 diabetes causing sort of kidney disease.

At the same time, hypertension, which is high blood pressure, which was sort of the second biggest cause of kidney disease, it was getting better because the treatments were better. We're actually diagnosing people way earlier with high blood pressure. So in fact, the numbers start to get skewed because I have less of the sort of hypertensive kidney disease and much more of the type 2 diabetes. So about 2010, 2011, I started to realize, hey, I think we're doing this all wrong, which is quite…

Michael Gervais (3:26)

Pause there. I'm sorry to totally interrupt you a bit because I want to know that moment. The moment that you said, we're doing it wrong. Can you call that back up? And I'd love to open the aperture and understand how you had a moment because what you've done from this moment has been meaningful and significant and really helped a lot of people. So I want to go into that moment.

Jason Fung (3:48)

Yeah. So it just sort of came to me. I was just thinking about it one day. I think about kidney disease a lot, right? Because every day that's who I see. And so I'm thinking about it, thinking about it all the time. But then suddenly I sort of switched. I looked at it a little bit differently. And that's when I said, I think we're doing this all wrong. Because if you think about it, the very word diabetic kidney disease means that you shouldn't just treat it with drugs or dialysis, which is what I've been doing. You should get rid of the diabetes. Because if you get rid of the diabetes, you don't get the diabetic kidney disease, right? So that's when I started to think, okay, so why don't you just get rid of the diabetes, right? Type 2 diabetes. And that's because people were saying that type 2 diabetes was a chronic and progressive disease and there was nothing you could do about it, but take your drugs, right? And then I thought about that for a second. And I thought, that's all wrong. It's a big lie because everybody knows. So every doctor knew, every patient knew, every nurse knew that if you lost weight, your diabetes would either get better or go away. And we're talking type 2 because there's actually two types, right? Therefore, this idea that hey, you know, type 2 diabetes is incurable and progressive is all wrong because it's clearly a reversible disease. Everybody knew it. If your friend had type 2 diabetes and, you know, he's taking medication and lost 50 pounds, he'd get off his medication. What are you going to say? You're a liar? No, he's obviously better and everybody had seen it. So why would we say this to ourselves? And I thought about that for a while and I thought, well, okay, so the problem is not necessarily the type 2 diabetes. You got to keep going back upstream, right? You got to keep going back up and up. The problem is the weight loss. You got to get people to lose weight. And that's really the key. And that's where I really became interested in the question of weight loss. And that's where I also thought, oh, the science behind this is like crap, right? And that was sort of how that whole thing started, because the type 2 diabetes is actually a reversible disease. My second book was all about that, The Diabetes Code. And in fact, they changed the whole definition. So two years ago, the American Diabetes Association finally admitted that it's a reversible disease and put in criteria for remission, which means you can reverse this disease, which is a complete difference from the messaging before that.