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[Music] Benna thought today we would talk a little bit about fuel, a little bit about putting things in our bodies that help our bodies run. My mom always taught me, "You are what you eat," and you have to put the right things in your body to get your body to work the right way.
Yeah, and it's certainly confusing out there to look at what it means to have a healthy diet and what it means to eat right. Those are words that, the longer I practice medicine, the more I can see there's room for misunderstanding, confusion, right? Help me understand what our bodies, what are the only things our bodies can use for fuel, and how these fuels that we eat, but they're basic fuel molecules are that our body actually uses at the bottom level. You know, we can skip the pathways, but what is it that our bodies are using depending on what we eat for fuel, right?
So, we, we do, um, it is a pretty safe, maybe broad, but safe conclusion to say, we, the fuel we eat is the fuel that we use. And so, we have the three main sources of fuels. We've mentioned before, carbohydrates, which when we eat a lot of, we use more of. Fats, which when we eat more fat, we use more fat. And then protein, which is never really a substantial source of fuel. It's mostly just a nutrient to build the body up. Those are the three typical, um, fuels.
Now, of course, as someone starts to lose weight because insulin is down, that does shift their body to using more fat for fuel, away from using glucose for fuel. And in fact, that becomes a very, we can measure that in people. That's something called the respiratory exchange ratio, and we can look at how much oxygen are they using, how much carbon dioxide are they breathing off, and that different ratio can decide or dictate or indicate, is this person primarily using glucose for fuel or primarily using fat for fuel? And the more we shift them towards using fat for fuel, the better, the more likely it is that they're going to be losing weight. There are studies to support that idea. So, we want the person to be shifting away from being a glucose burner to a fat burner. And that happens when insulin comes down. That's a very important adaptation. With as insulin lowers, it opens up the doors to the fat cells, and the fat cells begin sharing their fat with the body, especially the muscles, and the muscles will gobble up that fat to use for fuel.
Very well. Now, however, when I mentioned lowering insulin, I'd said that we had those three sources of fuel. When insulin is down, we actually introduce a fourth fuel in the body, and that is a molecule called a ketone. And the ketone, very briefly, a ketone is made in the liver. We're making them to varying levels all the time, but it's made in the liver when the liver starts degrading or oxidizing or burning fat very quickly, like when someone is eating a low-carb diet. That means that they're using a lot of fat for fuel, and their insulin is low, which means they're not going to store the fat. Where we're burning so much fat that we start turning some of this extra burning into ketones. And the ketones themselves can be lost from the body in our breath and in our urine, but also used as a fuel. Any cell in the body, except the red blood cells, can use ketones for fuel. And so, it becomes a very viable fuel source.
Now, that is, in and of itself, a benefit, and there are very distinct benefits of ketones. But before we mention that, I'm sure when someone hears the word ketone, they're just thinking of, "Oh, I had a, I had a roommate or a neighbor who was a type 1 diabetic, and they got into a diabetic coma or a diabetic ketoacidosis." And, and that can happen where, where someone truly has a deficiency of insulin. In other words, type 1 diabetes, it's usually overwhelmingly that's the cause, or when someone truly doesn't have enough insulin being made from their, in their body. Their insulin is so low that there's the ketones just keep getting made.
So, if I'm eating a high-fat, low-carb diet, I'm still making some insulin all the time. Yep. You could eat, not that I'm telling someone to do this, but someone could eat no carbohydrates, and they're still gonna have normal, but healthy levels of insulin. And that low, healthy level of insulin is enough to keep the production of ketones. It'll allow it to go up, but not dangerously over. And so, that enters into this realm, and it's a term worth knowing, ketosis versus ketoacidosis. And ketoacidosis is when there's no insulin, and ketones have gotten so high that it's made the body acidic, and it's dangerous. Okay. That would be a type 1 person who, wonder injecting their insulin for whatever reasons, maybe they have an infection, or they're not managing their diabetes correctly. They have a change in their acid-base balance in their body that affects how all their cells are functioning. You know, they become too acidic. Heat or acidosis. That's right. And then for the rest of us, we eat a low-carb diet, our insulin comes low, our ketones go up, but not dangerously. It's just into a realm called ketosis.
So, could I ever go into ketoacidosis from ketosis if I'm, if I'm, if I'm not a type 1 diabetic or I'm not? I know of, there's never been a paper, no evidence to suggest that that is possible. Right. But it is. So, I'm comfortable saying in the science, the science suggests that it is impossible to eat yourself into ketoacidosis. You would just get into ketosis. Yeah. I have many of my patients ask that question because their nephew, Little Jimmy, was in ketoacidosis. Right. And, and I'm asking them to move into an energy, an energy state called ketosis. That's right. And they're worried that that will happen to them. Yeah. And it will not. That's maybe, well, not. You can't. A healthy, non-type 1 diabetic cannot eat themselves low-carb into ketoacidosis, merely ketosis.
So, let me talk to you about the efficiency of this nutrition program. Because prior to me really understanding to how to control insulin as a basis for my health, I was taught to eat every two to three hours and a moderately high carbohydrate meal. And I would, I would eat a breakfast and come to work with my snacks all planned out. And when I would exercise and do my long rides or runs, I would always have my every 45 minute to one hour carbohydrate loads. Is, is does sugar tell me why I need to do that every two hours if I choose to use sugar, carbohydrates as my fuel source? Yes. Someone is glucose adapted, or their energy is sort of yoked to how much glucose they have. We have a very finite storage capacity of glucose. And so, if you are a glucose-fueled body, you're gonna need glucose all the time. Now, the tragedy of that situation is that's a body that will almost never have any ketones in it. And someone could struggle and say, "Well, who cares? What's the relevance of ketones as long as they are fewer?" Who cares? Yeah. Who cares? That's right. But that's really under appreciating a lot of the new research we have, including studies that we've been doing from my own lab, indicating the actual genuine benefits of ketones, where we find that ketones are potent inhibitors of inflammation. They act, just the ketone molecules themselves, suppress inflammation in the body. Ketones are a fuel source for cells that, as it's getting used, creates less oxidative stress. Ketones are a fuel that when you give it to the brain or nerves, they work better. And this is relevant to Alzheimer's disease, where some of the best studies are in people with Alzheimer's disease, that when we increase their ketones, we have these periods of improved thinking, a clarity of thought, better cognition, a brain starts to work better.
But let me just ask you this question then, because as a medical student, I was taught that the brain needs sugar to survive. And it's supported in the fact, we take Little Jimmy, our type 1 diabetic, who over injects his blood sugar drops, and he goes into some sort of unconscious state for whatever reason. And that's because his brain didn't have enough sugar. Many of my patients worry that if they move into a low-carbohydrate, high-fat state, that their brain will be affected negatively because they won't have sugar, which it needs to. So, ya.
No, I love you mentioned, I love you mentioned the type of diabetic. And so, let's just talk about that very briefly, and then get into the actual source of fuel for the brain. Well, in fact, let's start with that. The source of fuel for the brain is glucose and Keith. So, the brain can use both. And in fact, one, some of the studies from decades ago took people and did several days of fasting or what you could call starvation, and looked at how does brain fuel use change. And after about three days of a fast, they found that 75% of all of the brain's energy was coming from ketones, and the brain was only using 25% of glucose to meet, well, to meet its needs. So, very much shifted towards keto. And a faster, go without any food, my body runs out of sugar, it has to move over to burning fat, which a byproduct of is producing these ketones, which will fuel the brain. So, my body is prepared for this. Absolutely. We're built for it. And enjoy. If it doesn't even have to be fasting, that happens with low carb as well. As ketones go up in the blood, the brain begins using it. In fact, the fact that the brain begins using ketones once they become available, you could, in fact, come to a tentative conclusion that perhaps that's evidence that the brain prefers ketones, because once the ketones are there, even though there's still glucose in the blood, it starts to shift its preferential use towards ketones and away from glucose.
Now, in the case of the type 1 diabetic use, that's a, it's a wrong conclusion to say, "Well, Little Jimmy over injected insulin and now he's become hypoglycemic, and then the brain shuts off." But it still comes back to the ketones, because when Little Jimmy over injected with insulin, not only did he push his glucose too low, he also stopped making ketones. And so now we have a state of too little glucose and too little ketones. Other brains lost because this one was high that inhibits ketones for being produced. That's right. And that's where he runs into trouble. That's right. So, that's the exact opposite situation of what we have in an unhealthy person, non-diabetic, non-type 1 diabetic, adopting a low-carb diet. Glucose load in the blood comes down, insulin comes down, ketogenesis and the liver starts happening, and now they get into that realm of ketosis. As ketones to be made. Yes. And then we start using them. And beyond using the ketones, I'd said how they're anti-inflammatory, they have produced fewer reactive oxygen species or less oxidative stress. We found in my lab that ketones also increased metabolic rate, and it starts to have fat cells act in a faster state, and it makes them more metabolically active. And that could explain why there are multiple studies that find that when you put someone into ketosis, their metabolic rate goes up.
Help me understand, just for those who are wondering about it, well, or don't you still have a higher acid state in your body if you're using ketones as a fuel source, and doesn't that over time hurt your liver and hurt your kidneys to have this higher acid state because of ketones? No, it doesn't affect pH at all. We remain as neutral and normal in a pH range as ever before. It's, it's, it's just such a subtle increase in ketones that we can handle that without any consequences. So, all of these concerns that my patients company with, I can with assuredness tell them that the body is, is able to perform this way. In fact, in many ways, it prefers to perform this way. And all of the, all of the mechanisms that it uses can control for pH, can control for acid-base balance. And, and as far as we know, the data supports that there's not any harm to the kidneys or the liver over time being in a constant state of ketosis, which is again, not ketoacidosis. That's right. There are people that have lived in ketosis to control things like seizures and migraines their entire lives, and they, they have no long-term problems for this.
Help me understand one other thing about sugar versus ketones. When I eat a sugar meal, and I'm not diabetic, because I know diabetics can actually urinate out sugar when they get so high, is my body usually very efficient at storing all the extra unneeded energy in that sugar meal? Is that right? Yeah. What does my body do with the ketones, the excess ketones? Yes. So, there is no storage for ketones. It will use the ketones or it will get rid of them in the urine or the breath. And that's not a sign of pathology, or it's not a sign of disease. It's just ketones aren't stored. They are used. And there, you can say that because insulin must be low for ketones to be made. If insulin is low, then the body's not storing energy, it's using it. But that introduces this novel new area of exogenous ketones, or drinking ketones, or we have entire companies that are based on the idea of drinking ketones. And there is some relevance to that, but in other ways, it's not in this misinterpreted. We're talking about ketosis in the context of metabolic health. For me, as a scientist who studies insulin, the benefits in part of ketones is that by looking at someone's ketones, I can come to a general conclusion of what their insulin levels are. And if their ketones are up into the range of ketosis, then I can conclude, ah, you're in ketosis because your insulin is in control. Someone can drink ketones and get into ketosis, and yet they could drink those ketones while eating a bagel and say, "Hey, look, I'm measuring my ketones from my blood or on a urine strip, and I'm in ketosis." While eating chomp on their bagel, which is increasing their glucose, which is increasing your insulin. In that instance, the body would be turning ketones into fat and storing the ketones. However, so no. Well, I'll back up. I'll say this. Exogenous ketones may have a part in fueling the body for sports. That's right. Drinking ketones may be relevant for someone who needs ketones for fuel during an athletic event. If it's a fat-adapted athlete, they can drink the ketones to fuel the body. It may also help control inflammation, and it could help improve cognition for a period of time. But if someone's drinking ketones wanting to improve their metabolic health, that's not the way to do it. You want to be in a state where you're making your ketones and drinking them.
So, if I'm a type 2 diabetic, and I want to stop the disease progression of all the things that type 2 diabetes does because of high insulin, yep, and, and high blood sugars, drinking ketones is not going to give me the same benefit as eating a high-fat, low-carb diet where my body produces its own ketones, because it implies that I have stopped, or at least halted to some extent, all those disease progressions from that. That's right. That's right. We're not doing this. The end result isn't just ketosis. If the end result of all of this were just getting into ketosis, then drinking ketones would be fine. Right. But because our aim is to help people appreciate the relevance of insulin in disease, drinking ketones does not solve that problem. Right. We still have high insulin problems. That's right. So, as my analogy to my patients is, it's like going to the supermarket and buying vegetables and taking them and setting them in your garden and saying, "Look what a wonderful vegetable garden I have because of all these vegetables." Yeah, you have the end product, but you didn't take what it needs to get to that end product.
Well, thank you for answering that question. Thank you, Dr. Beckmann, for spending time with us today talking about a very complex issue of ketones and fuel sources. Thank you.
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