Essentials: The Science of Eating for Health, Fat Loss & Lean Muscle | Dr. Layne Norton

Welcome to Huberman Lab Essentials, where we revisit past episodes for the most potent and actionable science based tools for mental health, physical health, and performance. I'm Andrew Huberman, and I'm a professor of neurobiology and ophthalmology at Stanford School of Medicine. And now for my discussion with doctor Lane Norton. Doctor Norton, thank you so much for being here. This is a long time coming, and I have to say, as a fellow PhD scientist, I feel a great kinship with you. I know you have tremendous experience in fitness and nutrition in a number of areas. I'd like to start, with something that's rather basic and yet can be pretty complex, and that's this issue of energy balance and energy utilization. What happens when we eat food of any kind? And how is that actually converted into energy as a way of framing up the discussion around weight loss, weight maintenance, weight gain, and body composition? It's a great question. And like you said, this is one of those things where, you know, people use the term calories in calories out, and they say, well, that's way too simplistic. And I'm like, if you look at what actually makes up calories in calories out, it's actually very complicated. So a calorie just refers to a unit of energy, of heat specifically. Really what you're talking about is the potential chemical energy that is in the bonds of the macronutrients of food. Right? And by digesting, assimilating, and metabolizing those nutrients, we are able to create energy. The end product of that mostly is ATP, adenosine triphosphate, which is your body's energy currency. So a lot of metabolism is simply creating ATP. Protein's a little bit different because protein, gets converted to amino acids, which can be used for muscle protein synthesis or protein synthesis in other tissues, But, it also can be converted through gluconeogenesis to glucose and there also are some ketogenic amino acids as well. Then, you have fatty acids which are able to create energy through what's called beta oxidation, where essentially you're taking these fatty acids and you're lopping them off two carbons at a time to produce acetyl co a, which again can go into the Krebs cycle, produce those hydrodions that can then power the production of ATP. So that's kind of like at the cellular level of how this stuff works. But stepping back and taking it back out, like, what does that have to do with weight loss or weight gain? Right? When you think about the balance of energy in versus energy out, sounds very simple. But, let's look at what actually makes up energy in versus energy out. First of all, you've got to realize that the energy inside of the equation is more difficult to track than people think. So one, food labels which we like to think is being, you know, like from upon high, can have up to a 20% error in them. Really? Oh, …