Scientist with New Data on fat, weight loss and longevity | Dr. William Li Pt 1

Summary

Impact Theory Podcast Summary

Episode: Scientist with New Data on Fat, Weight Loss, and Longevity | Dr. William Li Pt 1
Host: Tom Bilyeu
Guest: Dr. William Li
Release Date: May 18, 2023

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Episode Overview

The conversation delves into the nuances of body fat, metabolism, and the relationship between weight and health. Dr. William Li, renowned for his groundbreaking work in disease therapeutics and the author of "Eat to Beat Your Diet," discusses emerging scientific evidence that challenges dogmas around obesity, metabolic health, and longevity. Tom Bilyeu presses Dr. Li to clarify the complex data and what it means for our health beliefs, particularly the contentious idea that being overweight does not equate to automatic poor health.

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Key Discussion Points & Insights

Challenging the Dogma: Is All Fat Bad?

• Not All Fat Is Harmful:

  • Dr. Li reveals that fat is a critical organ, forming early in fetal development (10:10–11:05).
  • Having some body fat is essential for metabolism, hormone production, and physical protection.
  • “If you didn’t have body fat, you wouldn’t have a metabolism. You need body fat.” – Dr. Li (03:47)

• Danger of Excess and Deficiency:

  • Too much fat disrupts metabolism, but overly little fat is also dangerous (09:03–10:02).
  • Notably, studies indicate being underweight can be riskier than being overweight in terms of mortality.
  • “You're far more likely to die of all cause mortality if you're underweight than if you're overweight.” – Tom Bilyeu paraphrasing Dr. Li’s work (09:03)

Nuances of Obesity and Health

• Body Size vs. Body Fat:

  • Body size (large frame, muscle mass) is not the same as unhealthy fat accumulation (06:03).
  • Example: Sumo wrestlers are metabolically stable during peak training despite high body fat (06:25–07:39).
  • “Just because you’re big doesn’t mean that you’re sick.” – Dr. Li (06:49)

• The Skinny Fat Phenomenon:

  • “Lean diabetes” or “skinny fat” individuals can be more metabolically at risk than visibly obese people (09:03–10:02).
  • “If you have lean diabetes... you’re more likely to die than if you were obese and had diabetes.” – Tom Bilyeu paraphrasing Dr. Li (09:03)

What Does Body Fat Actually Do?

• Fat as an Endocrine Organ:
  • Fat produces hormones such as leptin, adiponectin, and resistin, which regulate energy, metabolism, and appetite (11:10–17:26).
    • Leptin: Regulates fullness/hunger.
    • Adiponectin: Enhances insulin sensitivity (“the grease to allow insulin to bring fuel in”).
      “Adiponectin in your body would be 1,000 times higher than any other hormone in your body.” – Dr. Li (15:59)
    • Resistin: Acts as a metabolic brake.

Metabolic Dysfunction and Fat Accumulation

• Visceral Fat Dangers:
  • Visceral (“deep belly”) fat is more harmful than subcutaneous (under-skin) fat, fueling inflammation and metabolic syndrome (32:05–36:27).
  • “Too much visceral fat… is like a baseball glove of fat wrapped around your organs, and it’s filled with inflammation when it’s too big.” – Dr. Li (32:05)
• Overflow and Fatty Liver Disease:
  • When fat storage exceeds the ability of fat cells, fuel "leaks" out, leading to liver damage (21:05–25:06).
  • Non-alcoholic fatty liver disease is now the leading cause of liver transplants in the U.S. (24:35–25:06).

Can You Be "Healthy at Any Size"?

• Debating Health at Any Size:
  • Visibly assessing health based on size alone is insufficient; some thin people have dangerous visceral fat and poor markers, while some large individuals (like sumo wrestlers) can be metabolically stable if lifestyle factors are on point (39:35–43:37).
  • On extreme obesity: “Those people are clearly not going to be healthy. And those people have very shortened lifestyles.” – Dr. Li (42:24)
  • “It’s very difficult to judge by the size of a person, except at the extreme.” – Dr. Li (42:40)

Longevity, Caloric Restriction, and the Metabolic "Bank Account"

• The Caloric Bank Account Theory:
  • Tom raises the idea that perhaps there is a 'limit' to how many calories a body can process over a lifetime, referencing caloric restriction’s proven benefits for lifespan (48:54–50:36).
  • Dr. Li acknowledges it’s an intriguing, but unproven idea, and suggests more research is needed.

Diet vs. Exercise & The Four Pillars

• No Silver Bullet:
  • Dr. Li asserts both diet and exercise are inseparable for optimal health, emphasizing also sleep and stress management (53:03–53:52).
  • “They go hand in hand. You could have a perfect diet and do no exercise and you’re going to be compromised.” – Dr. Li (53:03)

The Quality of Calories

• All Calories Are Not Equal:
  • Whole foods (even at high calorie levels) differ widely from processed foods in their effect on metabolism and health markers (55:00–end).
  • “It’s not just simply the unit of energy that’s calories, but the other stuff that accompanies it… that is important.” – Dr. Li (55:00)

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Notable Quotes & Memorable Moments

• [03:47] Dr. William Li: “Fat is actually good … If you didn’t have body fat, you wouldn’t have any energy. … Having fat is good, having too much fat is bad.”
• [09:03] Tom Bilyeu (paraphrasing Dr. Li): “You're far more likely to die of all cause mortality if you're underweight than if you're overweight.”
• [15:59] Dr. William Li: “Adiponectin in your body would be 1,000 times higher than any other hormone in your body.”
• [32:05] Dr. William Li: “That’s what skinny fat is. When you have too much visceral gut fat, it's like a baseball glove of fat wrapped around your organs and it's filled with inflammation when it's too big.”
• [41:38] Dr. William Li: “You would not be able to look at somebody and know what kind of body fat they have. … except at the extreme.”
• [42:24] Dr. William Li: “Those people [morbidly obese] are clearly not going to be healthy. And those people have very shortened lifestyle.”
• [53:03] Dr. William Li: “You could have a perfect diet and do no exercise and you’re going to be compromised. … So I think it’s really… these are the four legs of the stool for our metabolic health [diet, exercise, sleep, and stress].”
• [55:00] Dr. William Li: “Quality calories is absolutely critical. … It’s not just simply the unit of energy that’s calories, but the other stuff that accompanies it … that is important.”

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Key Timestamps for Important Segments

| Timestamp | Segment | |-----------|---------| | 01:00 | Introduction to Dr. Li and the episode theme | | 02:26 | Early myths about metabolism and body fat | | 03:47 | Fat as an organ: baseline importance of body fat | | 06:03 | Difference between body size and body fat; health of sumo wrestlers | | 09:03 | Dangers of underweight and "lean diabetes" | | 11:10 | Developmental role and functions of body fat | | 15:59 | Hormonal functions—leptin, adiponectin, resistin | | 21:05 | How fat “overflow” causes fatty liver disease | | 32:05 | Subcutaneous vs. visceral fat explained | | 39:35 | "Healthy at any size?" debate and visual assessment of health | | 48:54 | Theory of caloric ‘bank account’ and impacts on longevity | | 53:03 | The necessity of both diet and exercise (+ sleep, stress) | | 55:00 | Why calorie source and food quality matter |

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Flow and Tone

The episode maintains a highly inquisitive, myth-busting tone, with Tom pushing Dr. Li to clarify controversial or surprising assertions, and Dr. Li responding with careful explanations, analogies, and caveats. Technical medical terms are broken down for a broad audience, and lived examples—sumo wrestlers, babies, "lean diabetics"—are used to make concepts relatable.

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Takeaways

• Metabolic health is more nuanced than body size or weight alone.
• Fat is vital for hormone regulation and energy management, but both deficiency and excess have risks.
• Internal fat distribution (visceral vs. subcutaneous) is far more relevant to health outcomes than external appearance.
• You can’t meaningfully assess someone’s health (except possibly at extreme ends of obesity or thinness) without clinical measurement.
• Calorie quality, not just quantity, plays a crucial role in health outcomes.
• Lifelong habits—diet, exercise, sleep, and stress—are jointly essential to metabolic health and longevity.

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For those looking to navigate diet, weight, and health in a science-backed, nuanced way, this episode is a must-listen.

Transcript

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[Tom Bilyeu]

what's up guys? I'm really excited for part one of this two part conversation with Dr. William Lee. Dr. Lee has been a key part of developing 40 FDA approved therapeutics and devices for cancer, cardiovascular disease and more. So when I say this guy knows what he's talking about, I really mean it. And in his latest book, Eat to Beat yout Diet, he's upending some of the most long held and cherished beliefs in the medical community about how to address your health and body fat through diet. In this episode we talk about why not every person with excess body fat is metabolically unhealthy and we get into the debate around whether or not you can actually be healthy at any size. You guys are going to be surprised about some of the things that Dr. Li says on that one. I know I was There is a lot of incredible new research coming out that will directly impact how you approach your diet and lifestyle. And in this episode Dr. Lee lays out a ton of it and in ways that has already impacted my own choices. And I do not doubt for one second that it's going to impact yours as well. If you want more conversations like this, definitely let us know. By leaving a review and following the show. It makes a huge difference in helping us get the show out to more people just like you. I'm Tom Bilyeu and welcome to Impact Theory and your new book makes a pretty bold assertion that I would like to get straight into around fat and that being fat does not necessarily mean that you're metabolically unhealthy. That was scandalous when I read it. So how can that be true?

[Dr. William Lee]

Now, listen, I'm going to throw myself under the bus here. When I was in medical school, I was given the same lecture about metabolism that pretty much you can look up on Wikipedia. You know, it's a blah, blah, blah, blah, blah, chemical reactions. And everybody assumes that has these assumptions about body fat and metabolism, right? So you're born with a faster, slow metabolism. And if you're born with a slow metabolism, you're going to struggle with your food because you're going to actually gain a lot of body fat and struggle with your weight. That's what a lot of people feel. People always feel that, like your metabolism is going to shoot up when you're a teenager eating two or three dinners, bouncing off the wall full of energy. Must be metabolism going up. And then, of course, the main thing is that people in their middle age, like 30, is sort of like the last golden era of fitness. Once you get to 40, 45, 50, 55, menopause, all that kind of stuff, your shape's going to change because your metabolism is going to slow down. You're going to gain body fat because of a slow metabolism. And so I always wanted to figure out, all right, why does all that happen? And is it actually true that we're born with different metabolisms and metabolism naturally slows as we get older and that

[Tom Bilyeu]

being fat is bad for you? This is the part that I consider scandalous.

[Dr. William Lee]

Well, here's the thing. Being fat is a subjective statement. What I would actually say that my book addresses is that body fat isn't harmful at a normal level. Fat is actually good. The big discovery is that fat is an actual organ in your body that forms when you're in the womb. And in fact, if you didn't have body fat, you wouldn't have a metabolism. You need body fat. It creates hormones that drive, that fuel your metabolism. It sounds kind of weird, like it would be the opposite, but in fact, if you didn't have body fat, you wouldn't have any energy, all right? It's only when you have too much body fat, that basically entire system goes into chaos. All right? Too much body fat. A little bit of body fat is like air traffic control running the way it is, landing planes, taking them off the Runway. Too much body fat is basically like putting a rock and roll band into air traffic control tower, all right? And playing as loud as they can and having the crowds rush in. And now the air traffic controller is distracted, don't know what to do. And extra body fat derails your metabolism. So it's not a slow metabolism that causes you to gain body fat and gain weight. It's the other way around. Extra body fat slows your metabolism. So it's not quite right that being fat is good, Having fat is good, having too much fat is bad.

[Tom Bilyeu]

Let me ask a really pointed question that I took away from your book that you're going to say yes to this, but maybe not. In the book, the paraphrase that I wrote down was being big isn't necessarily bad. And so what I want to know is, can you be clinically obese and be healthy? Like, could you when you look at somebody, when I'll. I'll say it from my perspective, when I look at somebody who's clinically obese with love in my heart, I just think they're killing themselves. And just by seeing that they're obese, I know they're unhealthy. But when I was reading your book, it made it sound like I can't make that assumption. They may be, because it certainly isn't automatic that having that kind of body fat is good, but it may not be as automatic as I thought that that kind of body fat is bad.

[Dr. William Lee]

Great point to discuss. So body size is different than body fat and obesity. So people are big. They can be. They can have big body size. I mean, think about a heavyweight boxer or an Olympian who actually, you know, is a weightlifter. Those are big people.

[Tom Bilyeu]

Let's go to the example you give in the book, which is a sumo wrestler.

[Dr. William Lee]

Exactly. I was going to bring that up.

[Tom Bilyeu]

So I look at a sumo wrestler and I just assume they die young. 100%, no if, ands or buts. They are going to die young.

[Dr. William Lee]

The amazing thing is that they are actually at a peak of fitness when they're actually training and they're overloading their bodies and they. To develop that shape. They're very strong. They're metabolically stable. They don't actually have problems with glucose regulation.

[Tom Bilyeu]

What is metabolically stable mean?

[Dr. William Lee]

It means that they are able to process their food without having huge insulin spikes. It means that they're. They have normal, normal levels of energy. Their inflammation levels are not through the roof, which, by the way, is a matter of training, sleep, discipline, food. Their diet is very specific as well. But the point is that if a sumo wrestler isn't tragically ill for the period of their career, we do need to rethink. Just because you're big doesn't mean that you're sick. Now, chronic obesity coupled with poor diet coupled with that leads to inflammation coupled with poor sleep, coupled with stress, coupled with lack of physical activity. Okay. It's sort of. That's the train wreck that actually begins to happen.

[Tom Bilyeu]

What do we know about longevity of sumo wrestlers? Do they? Because like, you'll often hear the statement, and I haven't looked closely enough at the data to know if this is true, but it seems intuitively true that you don't get heavyset centenarians, like people that make it to that age. They're all going to be thin.

[Dr. William Lee]

I don't think that's necessarily true. It's what we would imagine to be true. I think people can be portly, they could be middling.

[Tom Bilyeu]

Any data on this?

[Dr. William Lee]

I don't know of any data that takes a look at. I mean, look, I think that what you're trying to get at is is there evidence that obesity actually is not harmful, but helpful perhaps, and that you could have better longevity by carrying around excess body fat? And the answer is no.

[Tom Bilyeu]

Yeah. I'm going to say your book paints a far more nuanced picture. And so the nitty gritty that I want to get into is around that. So the case that I'm trying to build to see if I can get myself on board with this idea, because reading that, and I happen to be researching two people right now that are both making a very similar claim in their books. And I was. So literally in the last 48 hours, I feel like I've had my world upended. And it's like, oh, the earth is round, it's not flat.

[Dr. William Lee]

What?

[Tom Bilyeu]

And so I feel on unshaky ground. So here's how I read your book.

[Dr. William Lee]

Okay.

[Tom Bilyeu]

There is a sweet spot. You can be too fat and you can not have enough fat. But there are two times in the book where you say that actually being skinny is the more dangerous thing. And so you said you're far more likely to die of all cause mortality if you're underweight than if you're overweight. So that was startling. Statistic number one. And then the other one was that if you have lean diabetes, which I'd never even heard that phrase before, but I get it, what I used to call skinny fat. So if you have lean diabetes, you have the blood markers. Like if I was looking at your blood panel, because metabolically you're just a mess, I would assume that you were obese, but in reality you're not. That that's more dangerous 2.5 times, you're more likely to die. I don't know. I can't remember if it was all cause mortality or a heart disease or whatever. But you were two and a half times more likely to something terrible if you were lean diabetes than if you were obese and had diabetes. So I was like, whoa, this really does feel like the table's been upended.

[Dr. William Lee]

Yeah. So let's kind of do a reset to say, what does body fat actually do? Okay. And. And I, you know, so as I was writing this book, because I'm very curious about where things come from. Where does fat come from? Fat isn't. You know, we associate fat as adults as, you know, something we see in the mirror and we step out of the shower and we might not like what we're seeing, or step on a scale and you look at a number, it's not what you're expecting, and you kind of curse it, right? Or you walk to the grocery store and you walk by the butcher section, the meat section. You see nice steak with a big rind of fat on it. You go, ugh. Like, it's. It's. We're. We're, as a society, I think that we have some repulsion to the idea of seeing anything that's associated with fat. But it turns out that it's not always true. When we look at babies, when babies make us smile, they're pudgy, they're fat. Big pot bellies, big fat cheeks. Our arms and legs are like balloons twisted together, like in a, you know, in a carnival. It's cute on the baby.

[Tom Bilyeu]

It's not. Not cute. Like, if I rolled out of the shower looking like twisted balloons, I would not be impressed.

[Dr. William Lee]

That's true. But on the other hand, if you had a baby that had chiseled cheekbones, long, thin arms, long, thin thighs like a Runway model, that would also not be cool. You would think that that baby is sick. And indeed it would be. And so the real question that I started asking is, what is the developmental role and what is the adult role of body fat? When does it start and what does it do over the course of our lifetime? Because you talk about longevity. So what does actually this thing called fat actually do? Where does it start and where does it go? So here's actually the interesting thing. Body fat starts in the womb at about eight weeks after your mom's egg met your dad's sperm. And the first tissue that gets laid down are blood vessels, because every organ needs a circulation. Then the next tissue are nerves, because you need instructions to be able to operate your organs. And the nerves convey those instructions. Another tissue that forms right after that is fat. Fat. The cells that comprise fat are called adipocytes. Okay, Adipose tissue adipocytes. And the way that they form looks like bubble wrap. You know the bubble wrap you use for packing? Right, the small bubble wrap. And what they do, it's like they bubble wrap around blood vessels, and you go like, okay, so they're not forming, like, in the waist or the butt right away. Why do they form around blood vessels? Well, it turns out this has to do with a later fate of what the fat cells actually do for you. Fat cells. One of the functions that they do, they're padding. Okay? So good thing we have fat to pad is that we didn't have any body fat. We slipped on a rug, fell on the ground, our organs might rupture. All right, so padding is good. Number two, fat. And this has to do with the blood vessels. Fat cells are fuel tanks for our energy. All right? So our metabolism relies on fuel tanks, just like your car relies on some kind of either a battery or a fuel tank. And when your fuel runs low, you got to actually go to the filling station or the charging station to tank up, fill up on your. Your. Your fuel for your car. Similarly, when our fuel tanks run low in our body under healthy conditions, okay, we have to go pull over to the filling station. What happens to be a dinner table, a refrigerator, pantry, restaurant? To be able to fill up on our energy, which comes from our food. And our metabolism uses all the energy it needs to kind of run its operating system. So blinking heart beating, walking around, but anything extra gets stored in those adipocytes into our fat. Now, why are they near blood vessels? Because when you swallow food, you digest it from your stomach, it gets absorbed, or your small intestines gets absorbed into your bloodstream. And guess where the energy needs to get stored? Right in the fuel tank, right out of the blood vessel. So from a time where babies, before we're born, that's where the fuel tanks are. All right? And that's one of the things that it does. Padding, fuel tank. The third. The. The third thing that fat does for normal, healthy function, for metabolism, for health, is is it actually is an endocrine organ. So our fat releases hormones, normal, healthy hormones for our metabolism. At least 15 hormones have been identified from fat that fat makes almost exclusively. And three of them are critical for having normal energy, normal metabolism. Our fat controls normal metabolism in healthy people. So what are the three hormones that I want to talk about? Number one, something called leptin. Now, you might have heard of leptin as sort of like the satiety hormone. It makes you feel full. But I like to explain leptin as a volume switch. When you actually have a lot of leptin, you are not that hungry. But if you can talk, you can. It's not a toggle, but you can actually turn it down. When the leptin goes lower, you got to fill up on your fuel tank because you're hungry. So it's part of our gas, our fuel gauge to let us know if we're hungry and we need to fill up or not. Okay? Very important, because if we didn't know we need to fill our tanks, we'd starve. All right. It's a signal. Second, there's a hormone called adiponectin. Okay? And many of your listeners may not know what adiponectin is. I'll tell you if I, Tom took you into a medical clinic, drew your blood for a regular physical exam, and told the lab from a vial of blood to measure every hormone in your body and tell me what the levels were, including adiponectin, that adiponectin in your body would be 1,000 times higher than any other hormone in your body. A thousand. Now, why is it that important? Because adiponectin, which is made by fat, is what allows insulin to bring fuel into your body.

[Tom Bilyeu]

Is it a molecule that's calling for fat? Is it saying. Or for the insulin to come and

[Dr. William Lee]

store it partners with insulin to make insulin's effect of bringing in your blood glucose more efficient. It actually, insulin will do its job. Adiponectin will do it a lot better. In fact. So what happens is that if you screw up your fat and you don't make a diponectin. So let's say ultra skinny, somebody with less than 5% body fat, like bodybuilder type, all right, they're not having a lot of adiponectin. They actually have problems with energy because

[Tom Bilyeu]

they don't have enough fat cells because

[Dr. William Lee]

they don't know fat to make that adiponectin to have their insulin working.

[Tom Bilyeu]

Okay, I'm not following, though.

[Dr. William Lee]

Why.

[Tom Bilyeu]

Why does it. Why do we need such a high quantity? And do you know the mechanism of action? What is it actually doing? So I have a visual, I can put around what insulin does in terms of coming to the cell, looking for insulin receptors, and actually shuttling, typically glucose into the cell to actually store it as adipose tissue. But I don't know what a diponectin is.

[Dr. William Lee]

A diponectin binds to it's A different receptor on the same cell that insulin does. And it actually helps insulin's function. It actually triggers the. The pathway that allows insulin to bring in that energy more efficiently. Swifter. It's kind of like WD50. It's kind of like the grease to allow insulin to actually bring that fuel in. If you don't have it around, insulin will still work, but not quite as efficiently.

[Tom Bilyeu]

Your diseases were deponectin. Is it breaks down and we start having problems. And if so, what does that.

[Dr. William Lee]

Well, you know, I think that there are inherited diseases where adiponectin may be affected and, you know, people might not survive. They can't. Their metabolism. It's like inherited disorders of metabolism.

[Tom Bilyeu]

Would it have the same result as insulin resistance where you just can't produce enough to get it?

[Dr. William Lee]

It kind of like is like insulin resistance. Like insulin's not. Not performing what it, what it wants to actually do.

[Tom Bilyeu]

And do, you know, does the body respond to that by producing more insulin? Thinking like, oh, this is. I just need to keep shoving more in to get this out of the

[Dr. William Lee]

bloodstream to see if they can. So insulin levels will rise. And so basically, if you have too low amounts of body fat, you don't have enough adiponectin. All right, what happens is that your insulin is not functioning properly. Your body will make more insulin to see if it's maybe the problem's insulin, let's make some more insulin. So that's if you have too low body fat. Similarly, if you've got too much body fat. All right, by the way, before we go there, a diponectin brings the energy, helps insulin bring the energy in. A third hormone made by fat is called resistant. If a diponectin is the gas pedal, resistant is the brake. So you're eating fuel, you're eating food, you want fuel. Insulin is going to store it into your cells. So you're in the fast lane now. A diponectin goes boom. Pedal to the metal. Let's get in the fast lane to make our metabolism as efficient as possible. Let's bring that energy in, baby. All right, Resistant is the brake. Oh, got a truck ahead. Slow down. Not so fast. All right. And so this gas pedal, brake, accelerator, and brake works all the time to help fine tune our metabolism at different points of the day. Very, very important. Too little fat, like ultra lean bodybuilding, you know, or starvation, you know, type of situation, you don't have enough adiponectin, you're going to be very, very weak, and your insulin is going to try to rise, to compensate, but still it's not working efficiently. That's how important it is. Now, the other side of the spectrum, all right, if you have too much body fat, this is where fat functions, like a cancer. So fat, like any organ, requires a blood supply. But if you actually overeat and you have too much fuel stored, it's like going to the gas station. And instead of having to click in the nozzle when your tank is full, there's no click, it just keeps on pouring out gasoline. What's going to happen to your car? Gas tank fills up the gas. The fuel runs out of the tank, down the side of the car, around your tires, around pools around your feet. And now in a gas station, you're standing in a toxic, flammable, dangerous mess. Now, in your body, we don't have an automatic clicker. So to stop, all we do is we can keep on eating seconds, thirds, something delicious, or maybe even worse, something not good for you, like ultra processed foods or sodas. And you just keep on slugging it down. Your metabolism is you're is going to store it into body fat. And now your body fat can expand 300 times its size. Now, you cannot see body fat with a naked eye. You need a microscope to see the cell of body fat. But once it blows up 300 times, you can actually start to see these fat cells. All right, so you keep on eating, it blows up more. Keep on eating, it blows up more. More fat stored, more energy stored. Oh, run out of fat cells. Your fuel tanks are all stuffed up. Your body will tap into stem cells to make more fat cells. And now those will get filled up as well. So you can see how overloading on

[Tom Bilyeu]

fuel, when does it start? So when you get something like non alcoholic fatty liver disease. I assume we've filled up all of our cells.

[Dr. William Lee]

That's right.

[Tom Bilyeu]

We're not able to make new cells fast enough.

[Dr. William Lee]

Exactly.

[Tom Bilyeu]

And so now is their fuel, triglycerides.

[Dr. William Lee]

What happens is that the fuel leaks out of the fat cells.

[Tom Bilyeu]

In what form? It's actually like squeezing out.

[Dr. William Lee]

Well, it's stored in a particular triglyceride form in the cell, but when it leaks out, it starts to really become different types of short, medium and long chain fatty acids that are just seeping out. Okay. Of our fat cells that stay in

[Tom Bilyeu]

the blood, how do we get to something like non alcoholic fatty liver disease?

[Dr. William Lee]

Yeah, so chronic overeating is basically like chronically overfilling your gas tank. The fuel is going to start leaking out of the cells, out of the fat cells and it actually goes right into your bloodstream. And because your liver detoxifies your blood, it goes straight to the liver. And unfortunately, fat in that leaking form is toxic to liver cells. So as the liver is trying to clean to detoxify it, the fat toxins, the leaked fat toxins kill your liver, injure your liver, which then leads to scarring, which then leads to non alcoholic fatty liver disease.

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[Tom Bilyeu]

Interesting. So it's not actually an accumulation of fat on the cells of the liver, which is what I was imagining. I was imagining like visceral fat on the liver, but it's not. It's scarring the liver, it's actually destroying it.

[Dr. William Lee]

I mean, first the fat actually does accumulate, but then it's toxic.

[Tom Bilyeu]

All right, is it accumulating around the liver in the same way that it would accumulate around other organs, or is it because it's trying to process it

[Dr. William Lee]

out of the body, it infiltrates the liver. So if you look at a CAT scan of somebody who has visceral fat or a lot of subcutaneous fat, you'll see a rind of the fat in different parts of the body. In the liver, it's much more nefarious. When fat accumulates in the liver, it kind of penetrates the spaces between the

[Tom Bilyeu]

cells and just gets stuck there.

[Dr. William Lee]

It just gets stuck there. And while it's stuck there, it poisons and it's toxic to the liver cells. So it's fat plus liver. The liver cells are dying, the fat's still there. And then when the cells are dying, you know, your body's trying to clean it up, autophagy and all that other kind of stuff, except that there's. It can't regenerate fast enough. Liver actually regenerates, can't regenerate fast enough. And the toxicity causes inflammation of the liver and Then inflammation kills the liver more, and then scarring sets in. And now you've basically replaced normal liver cells with hard scar.

[Tom Bilyeu]

So if we catch that early, can we reverse it in diet?

[Dr. William Lee]

We can, but the problem is that non alcoholic fatty liver disease is kind of this slowly sneaking up on you disease most of the time. Like by the time you know, you have a problem or the doctor can detect you have a problem, it's really the end result. It's the car crash. You know, that was happening in slow motion for years. Right. But so, and, and by the way, this is actually one of the big epidemics, it's a pandemic really of non alcoholic fatty liver disease. It's the number one reason for having liver transplants now.

[Tom Bilyeu]

Wow.

[Dr. William Lee]

Used to be alcohol no more or hepatitis no more. It's now overload of fuel, leaking toxic fat that scars your liver, shuts it down, and now you need a liver transplant.

[Tom Bilyeu]

Okay, so why does alcohol create fatty liver disease? I get why. Overeating. And you just literally run out of storage space, which means it's in your blood, which means the liver's trying to clean it up. But with alcohol. Why isn't it just scarring from alcohol? When does it become fat?

[Dr. William Lee]

Got it. So look, check this out. Alcohol is directly toxic to your body. And the liver is very sensitive because the liver is desperately trying to detoxify the body, metabolize alcohol into, you know, something less toxic. All right, so on one hand, too much alcohol, it's not, you know, it's not a glass of wine, it's not a beer. It's chronic alcoholism that actually weighs on the liver by poisoning the liver, direct toxicity, but guess what? Alcohol is a sugar. So alcohol itself is overloading your cells. You gotta. It's gotta. It's gonna be stored into the fat,

[Tom Bilyeu]

which is gonna grow still, then running into the same problem. So is it literally. It starts as your cells are trying. Your liver's breaking it down, sending it to be stored. You're overfilling your cells. It's coming in too fast to make new cells. It's leaking back out of the cell. And now the liver is trying to clean up the fat. And now we have the exact same problem.

[Dr. William Lee]

That is one of the common pathways. However, don't forget alcohol that we sip, we drink, we chug. All right, the keg party. That alcohol is right in our blood and goes straight to the liver, all right, where it's poisoned to the liver.

[Tom Bilyeu]

But I'm trying to figure out why it's called fatty Alcohol disease, if it is what we just went through, and at first it overwhelms your metabolism, your fat stores are kicking it back out because it's just too much too fast and then we're back into the liver, then I understand the process. If it isn't that, I don't. Let me ask the question a slightly different way. You're a medical doctor. If I set before you a liver that had alcohol driven fatty liver disease, and I set one in front of you that had non alcoholic fatty liver disease, could you tell the difference?

[Dr. William Lee]

They would look different under the microscope because the alcohol itself poisons the liver. So it's basically, you see, alcoholic livers are actually shrunken. They're not as fatty. So you call it a fatty alcohol disease. Alcoholic livers are shrunken because actually they're poisoned and they start to decrease. It's true some fat can accumulate because alcohol itself gets metabolized and stored into fat. So over time. And by the way, this is not a, it's like I said, it's not a tr. It's not a light switch. It's not like if you don't drink, you're going to be fine. If you drink, you're going to be cooked. Your goose is cooked. This is a matter of degree. If you abuse food, even healthy foods, or you abuse drink over time, these are the kinds of things that can actually happen. So moderation, self control, discipline, taking it easy, you know, fasting, you want to go there. All those things can actually contribute to reversing. The good thing about the liver is that it's one of the organs in our body that clearly regenerates at a very, very fast pace. There's not that many organs that can actually do it quickly. But the liver, if I took your liver and removed any operating 2/3 of your liver, the one third that's remaining will grow the rest of it back over the course of a year. So injured livers, if you give it a break, cut down on your food intake, your caloric intake, stop drinking, the damage will start to reverse.

[Tom Bilyeu]

Even if you have scarring, well, at

[Dr. William Lee]

the point of scarring, no, that's there forever. That's, that's why you want.

[Tom Bilyeu]

Could you go cut out like, let's say that 2/3 of your liver is scarred. Could you go in and cut out a third or a half and get that to then regenerate? I assume it would regenerate healthily.

[Dr. William Lee]

Unfortunately, the damage can be very, very uniform. So you sort of just need to replace it. That's why liver transplant's common.

[Tom Bilyeu]

Interesting. Okay, I'll believe you. Obviously you know so much more about it. It seems like you should be able to cut a piece off and have it grow back, but.

[Dr. William Lee]

Well, it will try to grow back, except that once you've actually replaced healthy liver cells called hepatocytes with scar tissue, there's not enough cells working cells left to regenerate. Right. So. And by the way, when you regenerate, when the liver regenerates, it needs to grow within a happy medium of its own architecture. It needs to be in the garden of the liver. But when the garden of the liver is filled with scar tissue, it doesn't have enough stuff to hang on to. It can't reform a healthy liver. You've got scar that's kind of all in the interstices, is kind of penetrated the liver, mostly scar tissue, and you can't grow back.

[Tom Bilyeu]

The scar tissue won't do the regeneration process.

[Dr. William Lee]

It not only won't, it'll actually start. Any cells that do want to regenerate, it'll block their path because it's in the way. So you can't replace the scar. Wow.

[Tom Bilyeu]

Okay, that sucks. I want to go back to the sumo wrestler so that we can get to the. The full picture here of what I'm really trying to understand. Okay, so we know you need some fat. One of the earliest things that you get as a fetus is fat. Super important. We find babies cute because they're pudgy, because pudgy is good for them. As we get older, I know that we have a deeper road to go down, which will probably go down after we finish the sumo thing of these phases of metabolism. But it's. You need some fat for many reasons. But I certainly, before reading your book, and I think, even still, I think you're going to say this is true, that there is a point at which you become too fat and now the fat becomes problematic. And I'm wondering, is that point you're 100% fine. It is not negatively impacting your health in any way as long as the fat isn't being squeezed back out. Or is there like a BMI that you sort of ballpark and say, look, as long as you're under 15% body fat for a guy and 23% body fat for a woman, though I'm making those numbers up. But, like, you're fine. Is it that or is it. No, as long as it doesn't squish

[Dr. William Lee]

back out, you're good. It has to do with the fact that every individual has their own optimal amount of fat in their body that they carry around.

[Tom Bilyeu]

And how do you know when it becomes a problem? What are the signals?

[Dr. William Lee]

The metabolism is a great, actually, clue. Obviously, you can measure. So first of all, fat comes in different forms. White fat, brown fat. The white fat can be under the skin, subcutaneous under the skin.

[Tom Bilyeu]

Why don't you break down real fast? What is white fat?

[Dr. William Lee]

Okay, White fat is the most common fat. It's most of the fat in our body. And it looks white under the microscope. And it can be located in two. And it functions. It's a fuel tank. It actually gives a padding. And it can be located in two main areas. One is under the skin, which you can see. That's the wiggly, jiggly, lumpy, bumpy stuff that you see in a mirror. It's the muffin top. It's the thigh and butt. It's the stuff under the arm, under the chin. That's subcutaneous. You can see it then. A more dangerous version of white, of white fat is called visceral fat. Visceral means gut. So this is fat that's packed inside the tube of your body. All right, so you could be thin, be looking thin, have a thin tube, but have a lot of fat in there. Or you could be a big person with a. And have a lot of extra fat as well. Or maybe not so much fat. You just got a big frame. All right? The amount of visceral fat turns out to make a big. Have an impact. It's a more deadly kind of fat. Visceral fat. Think about it. Like peanuts that you would put into a container, you're shipping. Like you go to a FedEx and you're going to ship some light, some fluorescent light bulbs. So you're going to ask for a thin box. And now you got to pad that light bulb so you can ask for some peanuts. You can buy a big pack of peanuts. You're going to throw them in and you've got just enough. But, yeah, I don't want to waste the peanuts. I'm going to stuff them all in there. Okay? And now you've actually put way too many peanuts for that box. But you can force them in there so much that the peanuts are actually choking the light bulbs. Force the box shut, tape it shut at arm's length. That's still a skinny box. But inside, the peanuts are killing the light bulbs. That's what can happen. That's what skinny fat is. When you have too much visceral Gut fat. It's like a baseball glove of fat wrapped around your organs, and it's filled with inflammation when it's too big. Now, the reason that big, huge amounts of fat become dangerous is because they outstrip their blood supply. When you have normal amounts of fat, they're fed like every other organ in your body. But with blood vessels, you need oxygen, you need nutrients into your blood vessels. This is what I study. It's a process called angiogenesis, how blood vessels grow and when fat expands. Because you're loading up the fuel, okay, before it leaks, you're loading up the fuel. It's going to grow. Now you're loading it up. You need some more fat cells to grow. When it starts to grow beyond its blood supply, you can fill it up much faster than the blood vessels can grow. Then what happens in the center of that mass of fat? It starts to die. It doesn't have enough oxygen. And if it doesn't have enough oxygen, it starts to die. You get inflammation. Once inflammation gets into that massive white fat in your gut, the visceral fat. Think about that skinny FedEx pack with too many peanuts. Or it could be a big package as well. All right? It's also got too much packing in it. Then what happens? That inflammation completely causes chaos among the hormones that are there. Now, that fat that was making leptin, making a diponectin, making resistance, it gets confused because there's so. It's like a wildfire going on in there. It's chaotic. Leptin goes, well, I don't know. Should I be high or low? Should you be hungry or not hungry? I can't tell anymore. I forgot. A dip in Nectin goes well, should I be making more or should be less? I don't know. What do I do with insulin? I don't know. And so adiponectin start going up and down. Just like, remember I told you if you don't have enough fat, adiponectin goes down. If you have too much fat, it's inflamed. Your fat doesn't know how much adiponectin to make anymore. It's confused. It's got brain fog. Same thing as resistant, I don't know, break on or break off. And that's really the beginning of metabolic syndrome. How do you tell metabolic syndrome? You have insulin resistance, your glucose levels go high. You, you can have a big waist. Your waistline gets bigger, you got visceral fat. And by the way, with all that fat, you got a lot of blood. That's Got to kind of find its way around that fat. Your blood pressure goes up. It's not so easy to pump that blood through your body anymore. And that's what metabolic syndrome is. High blood pressure. Right? High blood cholesterol, high blood glucose and a big waistline. That's how you tell when you're saying, how do you know when you've actually exceeded that safe zone? These are the clinical signs that we see in the medical office.

[Tom Bilyeu]

Okay, so when you look at somebody and you see that they have a high body fat percentage, I'm thinking of the sumo. Still, you look at that and go, as long as it was accumulated at a rate that the blood supply could keep up with that accumulation, there's not necessarily a problem here.

[Dr. William Lee]

It's a little bit more complicated than that. Because excess amounts of fat, no matter what, are going to put pressure on your circulation, on your heart. Remember, I told you it's still hard to pump that blood even just through a lot of fat mass. That back pressure in your heart is going to actually wear down your heart. Now, I know you want to kind of focus on the sumo. I look at sumo as kind of an extraordinary, exaggerated and somewhat grotesque version of actually growing too much body fat. To see extent is of growing body fat but still staying healthy. Now, now sumo wrestlers are healthy because they're working out all the time and all that they're eating to create their big mass, all right? They're eating a relatively healthy meal. They're not eating french fries the whole time. It's a very regimented diet. They're exercising, they're getting diet, they're kept in stables, more or less of training, where they're actually getting sleep. And they have a very rigid schedule. And their stress levels outside of competition are really, you know, they're trying to stay calm most of the time. So these are all factors. These lifestyle factors also affect our body fat. Are we physically active? Are we getting enough sleep? What kind of diet? What's the quality of the food, the fuel that we're actually eating? How much stress do we actually have? And now we're realizing enterprise, a new dragon, which is actually our gut health, our gut microbiome, our gut microbiome, our healthy bacteria, 39 trillion of them in a healthy body, contribute to streamlining your metabolism. They work along with insulin, they work along with adiponectin to help your metabolism streamline, pulling in that energy.

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[Tom Bilyeu]

So I could have asked the question another way, which would maybe be even more informative as to why I'm focused on the sumo wrestler. And the other way to ask the question would be, if I wanted to get obese in a healthy way, could I do it? The reason I'm so interested in this question is there is a debate raging in culture, which is can you be healthy at any size? And up until 48 hours ago, when I read your book, I would have said no, you cannot. Absolutely, unequivocally, if I look at you and you have a. A dramatically high body fat percentage, I can tell you immediately you are shortening your life, period. End of story. And I would have been able to pass a lie detector test. But it doesn't mean that I'm right. It just means I believe it. And so reading your book, I'm like, maybe there is a way to get obese in a quote unquote healthy fashion, but I need to keep exploring it. You're definitely making me believe that this is a far more intricate picture than I was originally giving it credit for. Not surprised at all. As the island of my knowledge grows, so grows the shore of my ignorance. So I'm not at all surprised to find that I didn't know nearly enough. Uh, but I am still hung up on a lot of what I think I know about the metabolic signaling that fat does that. Getting fat is a sign that you have chronically elevated caloric intake, that you're probably overeating sugar, which is going to be another thing that we're going to need to get into. And that almost certainly people that get to that level of body fat percentage, they have not done it in a controlled fashion. And so I want to know if we just have to rule out and say, yeah, I really can't tell if you're healthy or not from looking at you. We're going to have to run a lipid panel or whatever metrics it is that we're going to look at.

[Dr. William Lee]

But, you know, what you're talking about actually is so important to say, which is, you know, as you were characterizing this, looking at somebody, you can judge whether or not they're unhealthy based on their body size because they're fat. Okay, let's break that down. You would not be able to look at somebody and know what kind of body fat they have. You could guess, and you might be right, but how much visceral fat they have. You know, somebody who's obviously obese. And we, We've all seen people like that. They're, you know, there's. That's a. That's a far. That's a. That's a far end of the. That's a. That's the tail end of the curve. Those people are clearly not going to be healthy. And those people have very shortened lifestyle.

[Tom Bilyeu]

I would put a sumo wrestler on that scale for me.

[Dr. William Lee]

But those people who are morbidly obese, they're not exercising. They're not eating a healthy diet. That's probably how they. Partly how they got there to begin with.

[Tom Bilyeu]

But what that tells me, fat isn't the. It becomes the lifestyle. That's the problem.

[Dr. William Lee]

Lifestyle contributes to the growth of fat. Excessive fat. Excessive fat. Right. And so what really matters for most people is actually the kind of fat you have and the extent of that. That kind of fat. Visceral fat's a lot worse. More white fat, more visceral fat. Those are setting you up. And, you know, the. The opposite side of the sumo wrestler is the apparently thin person who also is obese on the inside. You would never judge them to be obese. You might even think they're healthy, but they're probably not exercising. They're probably eating a very poor diet. And although you're not a human DEXA scan that could actually see the superman, to be able to peer inside the body and resolve, maybe the terminator, to resolve what kind of fat that they actually have. All right, they are, I wouldn't say equally unhealthy, but it's very difficult to judge by the size of a person, except at the extreme.

[Tom Bilyeu]

Well, according to your book, it would be the flip. If I look at them and I realize that they are lean, diabetic, they're in worse shape than an obese diabetic. So again, getting Back to. We have found the edges of what I understand. So that was a very surprising find for me. Okay, so knowing that, that reframes obesity for me. So as soon as I read that in your book, I was like, okay, so here's the prediction that makes, and I've certainly heard other people say this, that adding fat to your body is actually a metabolically protective mechanism. And that if you're able to put on fat more easily, you are probably in better shape because you have a way to get the excess glucose out of your bloodstream, store it as fat. And if you're able, I don't like, so I get fat very easily. My wife does not. So for me, putting on fat is very simple, which tells me that either my fat cells, maybe they do 320% bigger or something, or I'm just very good at generating the other ones.

[Dr. William Lee]

Or, or your metabolism is very efficient. So based on how much you're eating and the quality of the food you're eating, it gets stored into your fat quite efficiently.

[Tom Bilyeu]

I wish it was a little less efficient. Yeah, I hear you. So, okay, so they're, for some reason my body and people like me, they're able to get the, the excess sugar energy, however you want to look at it, out of the bloodstream into the fat cell. And that is very protective. And so now as they get bigger and bigger and adding on more and more fat, there is, from what I hear you saying, there are ways to do that. Well, and I don't yet know if you feel like it's. There is no longevity implication to the sumo wrestler as long as he's working out. In fact, maybe that's right. Let me just ask that point blank, would you estimate that sumo wrestlers as a population will live just as long as anybody else that eats a similar composition of diet, albeit clearly fewer calories?

[Dr. William Lee]

Look, sumo wrestlers are trained when they're young and they work out and they have a very regimented diet. I mean, and lifestyle, they're under control. But like any athlete, I mean, look at fat.

[Tom Bilyeu]

That's the part that I keep getting lost at.

[Dr. William Lee]

But, but here. So here's another. But here's another one. Think about other big athletes. You look at an NFL player, all right?

[Tom Bilyeu]

Oh, they die. They're big people, young.

[Dr. William Lee]

But you know, the reason that they, they, they wind up eating a lot of food. They have a huge caloric intake when they're working out. Now, I think it's getting better because they're actually trying to study that. But then what happens when they're, when they come off the field, when they retire, they're still eating that kind of food, maybe worse quality food. Now they're not working out. All right. Now they actually have a completely different lifestyle where they continue to eat a ton of food, maybe not high quality food. And so they're overloading, but they're not actually physically active. So. And that they're at a different point in their metabolic cycle as well. So the point of the matter is that it's an experiment that hasn't been done yet. If a sumo wrestler who gets trained when they're in their late teens actually continues to have their same lifestyle over the entire spectrum of their adult life, it'd be like an NFL player who basically plays ball until they're 6 years old. It doesn't happen. We can't do that experiment. We don't know how to do that study. If a football player were actually to do exactly what they do over the course of their life, would they live longer than somebody who stopped playing at the age of 30 and then went on to eat junk food and become sedentary for the rest of their lives? We can't compare that. So for a short period of time, sumo wrestlers go to a far extreme of body fat accumulation. Some would say even a grotesque extreme, in which you would think that they'd be metabolically unhealthy. You would think that they would develop diabetes, they would develop heart disease, they develop cancer. Like, because we associate this with older people who are obese. And the fact is that it's not true. They're actually remarkably fit for their size. But let's not forget, they're young, they're trained, their diet's regimented, they're exercising. Their whole life is actually contained and controlled. Because they stop their sumo training at a certain age, we won't know whether or not this early exposure is going to lead to premature death. Right. I mean, I would imagine that sumo wrestlers, after they finish training and I. And I don't know this, I mean, this is data. I don't know. As a scientist, I can tell you, an honest science just tells you when they don't know something. Sure. And I'm just telling you, I don't know if any studies have been done on retired sumo wrestlers and their metabolic consequences of their earlier training. It'd be something interesting to study. But in no case is getting fat young, protective of longevity, protective of other diseases as well.

[Tom Bilyeu]

Okay. So it isn't doing them any favors. We just don't know if it's doing any harm when it's done in that very controlled. So many aspects of the lifestyle are on point, but they're still getting fat. It's interesting. So here's the base assumption that's driving my obsession with sumos in this interview. You I have lurking in the back of my mind, even though very smart people have tried to tell me to let go of this, but it doesn't make sense to me yet again, could just be ignorance. I have a feeling that there's just only so much food calories that you can process in a lifetime and that you people tell me not to think of it like this, but I just think it is the right way to think about it, that the body eventually has done all the things that it's going to do, that whether it's gumming up because you've eaten a certain amount of sugar and all of that. And so just so many things stick around as they talk about forever. Chemicals, they accumulate, whatever. But the only thing that's shown efficacy for extending life in basically every animal that has been tried on is caloric restriction. So I infer from that, then, that, well, overfeeding, even if you're a Michael Phelps and you're staying shredded because you're just working all those calories off that, that you still. You ran those miles, man, like a car that gets 250,000 miles on it, it's going to have some wear and tear to show for it. And so the metabolic system has done those 250,000 miles. So even if you're lean, even if you're a sumo wrestler and you're in good shape, I've just. It just seems impossible that there isn't some sort of price to be paid for that.

[Dr. William Lee]

I agree with you. I 100% agree with you. I mean, you can actually. I think that it's an interesting kind of calculation to make, right? You eat three meals a day. Average person lives, what, 82 years old. Now, you can calculate the number of meals you're eating. You can calculate based on your body size how many calories you might or might not be eating every day. If you were ideal. You can calculate how many blood vessels are in your body. 60,000, 60,000 miles worth of blood vessels. You can calculate the number of times your heart's going to beat over the course of a lifetime. You know, and you can actually probably come up with a metric that approximates fairly accurately what the total caloric what the Goldilocks zone, the zone of tolerability of the calories that you could intake over the course of your life would be. And so to, to work with you on this thought process, this thought exercise. You know, I wonder if you were to eat more calories if you assume that there's a caloric bank account that you're limited to over the course of your lifetime. If you eat more in the beginning and less at the end, does everything balance out? Don't really know. You know, and I think it's because there's so many interconnectedness or you eat less in the beginning. You know, kids born during wartime that are starving, right. And then later on they, they have a period of prosperity, war's over. Now we got a job, and now we're actually exiting our company that we started. And now you just start to pig out. And so now later on in life, you wind up overfeeding. Net. Net from the, from your bank account. As long as you stayed within those calories, are you going to be okay now if you exceed those allowable calories? I'm playing this mind game with you. It's really interesting to think about. That'd be like a great model, like a research model to actually do. Like after this thing, I'm going to start to work on that. Probably because it's so interesting over the course of your lifetime.

[Tom Bilyeu]

Yeah, this is a really interesting question. I found the book so fascinating because you really pushing against some of the notions that I felt most confident in. So one thing as we're going through and we're talking about, you know, Michael Phelps or a sumo wrestler, I want to know, do you think it, what's more important, diet or exercise?

[Dr. William Lee]

Both are, both are equally important. There's no, you know, like, we always want to simplify it. Like, okay, do you want to be dropped in a volcano or eaten by a shark? Neither. Okay. And I think that when it comes to exercise or diet, they go hand in hand. They're different, but they do go hand in hand. You could have a, a perfect diet and do no exercise and you're going to be compromised. You could exercise your old time and go and eat a crappy diet, junk food, staple diet. And your exercise is, you know, you might look good for a period of time, but inside you're going to be terrible. And so I think it's really. And by the way, it's only exercise and food you're talking about. What about good quality sleep? What about stress management? You know, these are the four legs of the stool for our metabolic health.

[Tom Bilyeu]

All right, let's hold everything equal and let's talk now about quality of calorie. So if I were, let's say that I was going to grossly overeat and I have a normal, more or less sedentary life and I'm going to eat one person, my identical twin. My identical twin is going to eat 5,000 calories a day of ice cream and I'm going to eat 5,000 calories a day of a plant, primarily plant based diet with a little bit of fish and chicken and stuff, but I'm still eating 5,000 calories. It's not easy. Anybody that's tried it, I know, but I managed to get my calories in. So we both have the same overage. Will the blood will. Whatever metrics you look at, whether it's visceral adipose tissue, where it's stored, my cholesterol levels and what parts of that may or may not matter, the walls of my arteries, like, is there going to be any difference given that we're eating the exact same number of calories? This is for people who say it's just a question of calories. It doesn't matter what they're making.

[Dr. William Lee]

You know, the whole idea of quality calories is absolutely critical. You know, you can have a candy bar that has 304, a thousand calories, or you could actually have a garden salad that you load up that has the same amount of calories. Candy bar has got artificial preservatives and flavorings and colorings and saturated fat. Okay, Maybe trans fats. The salad is going to have the same number of calories. Okay. But it's going to, if it has a tomato, it's going to have lycopene that actually helps you burn fat, by the way, it activates brown fat, which we can talk about, which will help to burn down fat. It's got leafy greens, which watch. And maybe it's got a little broccoli sprouts and now it's got sulforaphanes. And so it's not just simply the unit of energy that's calories, but the other stuff that accompanies it. All right, that is important. I'll give you an example of something else that accompanies calories. So an orange, like just a regular piece of beautiful citrus orange that you might have ripe orange. Juicy's got a lot of sugar in an orange. Right. It's also. But it's also got a lot of dietary fiber. That dietary fiber doesn't quite count as a calorie, but it might partially count as a calorie. It's got polyphenols, it's got a lot of flavanols, it's got hesperidin, Nargen, and all these other factors. It's got a vitamin C, ascorbic acid, which lowers inflammation. And so although you might have an orange compared to a candy bar, just kind of fix it to a candy bar or a bag of potato chips. All right? A bag of potato chips does not have those polyphenols, does not have that dietary fiber. And so you the things that activate your body, the good defensive parts of your body, help to groom your metabolism, can indeed help you fight your excess body fat. All right, it's not the presence of fat. It's not a black and white thing. It's the degree. And now you can choose foods that can help you optimize your metabolism, help you fight body fat, and also help to activate other health defenses that will improve your longevity.