Professor Robert Lustig: Can you exercise your way out of a bad diet? #diet #obesity #shorts#lustig

Ultra processed food is actually not food. So if it's not food, what is it? Well, it's a toxin.

Welcome back to Emory Pharma's podcast series. Today we are welcomed by our honorable guest, Dr. Robert Lustig. My name is Niku Madhavian. I'm the director of operations and corporate development at Emory Pharma. We are a contract research organization with a mission to help pharma companies develop safe drugs and to treat various diseases. We're pleased to have Dr. Lustig back with us today to answer more questions. He had previous talks that covered a wide range of topics including the impact of ultra processed foods, sugar, fructose metabolism, fatty liver disease, and and different syndromes related to mental health and the role of personal responsibility and public health policies. So we are honored to have him here today. So, Dr. Lustig, thank you so much for joining us today.

Thanks so much for having me, Neetu.

Today we wanted to learn a little bit more regarding a very prominent soda company. We're not gonna mention any names, but they say that soda contains 140 calories, which is 7% of the daily reference intake of calories that an adult should consume to maintain a healthy diet. Do you agree that simply looking at calorie number is a little misleading? And can you explain why calories from sugary drinks like soda are more metabolically harmful than calories from other sources?

So, of course, Neetu, this is my whole raison d', etre, if you will. My job, you know, unwritten job, if you will, is to kill the calorie. Hashtag, kill the calorie. So what is a calorie? You know, where did it come from? Why do we even care about it? So a calorie is a unit of physics. It's a measurement. It is the amount of energy that it takes to raise 1 gram of water 1 degree centigrade. So it's basically a measure of heat, is what it is. And in that respect, if you are purely interested in the physics of doesn't matter where the calorie comes from, because the calorie is the heat. That's what the calorie is, is the heat. And so heat is heat. So therefore you would say, well, calories are calories. And that's, of course, what the industry says. Well, in order to measure a calorie from food, you have to take that food and explode it in a contraption called a bomb calorimeter. It basically blows up the food and determines the difference between the amount of heat to get it to blow up. And the amount of heat released. And that's how you measure how many calories a given food has. And it is true that a calorie burned in this bomb calorimeter is a calorie burned. That's true. But what is not true is that a calorie eaten is a calorie eaten. Then it depends on where those foodstuffs came from. And the reason is because we don't run on heat, we run on chemical energy called ATP, adenosine triphosphate. And how much ATP you generate is really the indicator of how many molecules of energy you actually get out of food. That's not heat. So from the standpoint of what it is you're measuring, calories are actually irrelevant. Okay, so turns out different foods will generate different amounts of ATP based on different properties of those foods. And I have, you know, explained this in, you know, podcasts before, so this isn't new. I mean, the best way to explain it is to look at different kinds of calories. Almonds are my favorite. You eat 160 almonds. How many of those calories did you burn? 100. You ate 160 calories. Turns out you actually only absorbed 130 calories. So you can only burn 130. So what happened to the other 30 that you didn't absorb? Turns out the fiber in the almonds, both soluble and insoluble, prevented their absorption, carried it further down the intestine, so that the microbiome chewed up those calories and generated their own ATP and generated their own heat, which is not part of you. It's the microbiome's energy and the microbiome's heat. So even though you ate it, you didn't get it. But you measured the calorie at your lips. What you really care about is measuring them at the intestinal brush border, because that's what gets absorbed. So a calorie is not a calorie, because if you ate it with fiber, the calorie wasn't for you, it was for your bacteria. So that's an easy way to, you know, explain this dichotomy. Second, protein. So protein, when it gets converted to energy, has to be cleaved into its component amino acids. Right? Amino acids are the constitutive building blocks of proteins. And so we have enzymes in our intestine that break up proteins into individual amino acids. Then we absorb those amino acids, and then if we're going to use them for energy, they go to the liver, they don't go to the muscle, they Go to the liver, and the liver has to take the amino group off in order to turn it into energy. So they turn that amino acid into an organic acid. And then the organic acid can then participate in mitochondrial function to generate ATP. It takes energy to pull that amino group off. So you actually have to invest energy to get energy out. So there's a net loss of energy when you're burning an amino acid as compared to, say, a carbohydrate. So you actually lose energy instead of gaining it because you will generate fewer ATP for the same number of calories. So a calorie is not a calorie because it depends on what it was you were burning. Number three, fats. So over here we have omega 3 fatty acids, heart healthy, save your life, anti Alzheimer's, single best thing you can put in your body. And over here we have trans fats. The devil incarnate, okay? Consumable poison will kill you in 10 years if you keep eating them. And we have the data to prove that they're both nine calories per gram. One will save your life, one will kill you, because a calorie is not a calorie. It's not about the calories. It's about the biochemistry of the molecules themselves. And finally, the one I spend most of my time talking about, fructose and glucose. So glucose and Fructose are both C6H12O6. Fructose and glucose are both 4 calories per gram. Glucose and fructose can both be metabolized to energy, but not the same way. Glucose usually goes to glycogen, fructose usually goes to fat, because they are very different. And it turns out that fructose is a mitochondrial toxin. It actually inhibits three enzymes that mitochondria need in order to be able to burn and create all those ATPs. Glucose, on the other hand, actually accentuates mitochondrial function. So at the level of the mitochondria, glucose is a stimulant and fructose is a toxin, even though they're both 4 calories per gram. So a calorie is not a calorie. It depends on the biochemistry of each individual foodstuff. So we don't care about the heat, we care about the ATP. And different foodstuffs are metabolized differently to generate those ATP molecules. This is why calories are irrelevant. And.