Transcription
(gentle rhythmic music) - Muscle health can often be overlooked as an important component of healthy aging and well-being. How does building muscle through exercise and preserving muscle tissue throughout the lifespan benefit overall health and aging? What is the role of protein in muscle health?
- In muscle, we have what we call anabolic resistance, and we actually need more essential amino acids as we get older. Just to give you a frame of reference for that, a 25-year-old will have a fairly robust stimulation of muscle protein synthesis with 15 grams of protein, where to get the same effect in a 65-year-old will require over 30 grams of protein.
(gentle upbeat music) - On this episode of "Pathways to Well-being," we welcome 2025 AIC speaker Dr. Donald Layman. Dr. Layman is an internationally-recognized expert in protein metabolism and muscle health, with a distinguished career in nutrition science, including over 120 peer reviewed publications. Today, we'll explore why muscle health is so important to overall health, the lifestyle based approaches that benefit muscle quality and preservation, and the important role that protein plays. So much to talk about today, Dr. Layman. Welcome to the show!
- Hi, it's great to join you. Thank you.
- Well, this is such a hot topic lately and perfectly timed to give a little preview of your AIC presentation. So, let's start this conversation with a more broad discussion about the function of muscle. We know that there's some mechanical functions: helps with our posture, our movement, stabilizing our joints. But will you get us started today by talking about some of the other physiological functions that really make muscle so important?
- Yeah. Thank you. You know, the role of muscle, the obvious role, we have structure and mass. It's part of daily activity. People don't really think about, it's functional for bone health. Actually, our bone health is very much related to it. So, more structural aspects. Our ability to survive things like a hip fracture or cancer therapy directly relates to bone mass. But I think probably the thing people don't understand is it's also our only voluntary link to metabolism. And so, our metabolic regulation from glucose metabolism to fatty acid metabolism also really is focused on muscle. If we're having problems with either glucose metabolism or fat metabolism, it probably means we have a muscle problem.
- Indeed, and I'm picturing maybe others who are listening are picturing the functional medicine matrix in their mind and looking at how muscle can impact so many different body systems. And I think we understand from a physical fitness perspective, you know, muscle is obviously really beneficial, but will you talk to us about how there might be some interplay with our cardiovascular system?
- (chuckles) Yeah, I mean, obviously, muscle from a mobility standpoint directly relates to your heart function, your vascular system. So, how big is the plumbing? Is it healthy and your heart's strong? And all that relates to physical activity and exercise. But as I started out, the aspect, you know, I like to tell people. If you encounter somebody who has a problem with blood sugar, if you encounter someone who has insulin resistance, that's a muscle problem. If you encounter somebody with abnormal blood lipids, high free fatty acids or triglycerides, that's a muscle problem. People don't recognize that muscle has a very important role in selecting our fuels. And what those things mean is that our carbohydrate and fat choices are out of balance.
- Well, I'm keeping notes so I can make sure to return to that later. But before I do, I have to ask you about mitochondrial function because mitochondria are my personal favorite thing to talk about. And I know that there's this relationship between mitochondrial biogenesis and exercise and there's so much impact in our muscle. Will you talk to us a little bit about those connecting points between our muscle tissue and our mitochondria?
- Yeah, so, you know, again, most people recognize me as a protein expert, but I like to think of really, our muscle-centric health is kind of the key to it. Exercise, particularly more aerobic types of exercise, have a big impact on the number of mitochondria in your muscle. And if your muscle's really healthy and you have healthy, reasonable numbers of mitochondria, the primary fuel in skeletal muscle is fat. So, the fuel distribution in skeletal muscle under normal healthy conditions should be about 80/20 fatty acids to carbohydrates. But when you stop and think about our American diet, we're eating about 55/35 carbohydrate to fat. We're eating the opposite direction. And that causes some very serious metabolic stress to skeletal muscle.
- Well, that's a perfect lead in to what I was planning to ask you about next, which is, I mean, you mentioned how important muscle is in our resiliency. And I'm imagining there's various ways that we're losing muscle or our muscle health begins to decline because of we're aging, we're more inactive, maybe we have some disease process going on. I mean, what is the biggest contributor to a loss of healthy muscle that you're seeing in just the common person?
- (chuckles) Well, there's two issues. One is just getting older.
- Yeah.
- I think one of the things people need to keep in mind is that if you just keep doing what you're doing, as Albert Einstein said, "You'll continue to get what you got." But I think it's important to recognize that for each decade you lose about 4% lean mass. So, if you continue doing whatever you were doing at 30, at 70, you're going to have a significant loss of lean mass. The other thing to keep in mind on that regard is that we lose about 100 calories of energy expenditure, resting energy expenditure per decade. So again, 30 to 70s, you're going to lose about 400 calories per day in energy expenditure. So now, what we need is higher protein, higher nutrient density, and fewer calories. The other aspect, and my good friend and colleague who passed away, Doug Paddon-Jones, indicated that aging is not really a linear process. It's actually, and he coined the term, "a series of catabolic crises" that as we go through life, we will encounter things. It might be COVID and bedrest. It might be breaking a bone and you're incapacitated or some other form. It might be a cancer and treatment. It might, you know, we encounter things and during each of these, there are significant losses of muscle mass. If you are 25, your loss over a two-week period might be three, four pounds of muscle mass, and you can gain that back quickly. But if you are 65, you might lose 14 pounds of muscle mass in two weeks and your ability to gain it back is extremely low. And without serious resistance exercise, probably negligible. So, basically we have normal aging loss and then we have what we refer to as catabolic crisis and sort of acute losses that get more and more important as we get older.
- Right, well, it seems like, maybe we get stuck in these patterns of eating the same foods we've always eaten and doing the same activities we've always done, but actually as we're aging, those need to change. I mean, is that something you're finding people just are not aware that they need to adjust their nutrition and their activity as they get older?
- Yeah, I mean, again, a lot of our dietary guidelines are based on 25-year-olds who tend to be closer to ideal weight, they tend to be more physically active. They can eat more calories. And so, we hear about, you know, the amount of protein people are eating and the amount of calories. And it's usually based more on young people. And as I've just said that, you know, as we get older, our resting energy expenditure goes down. We lose the amount of calories, and yet we still the same nutrient needs. And in fact, in muscle we have what we call anabolic resistance, and we actually need more essential amino acids as we get older. Just to give you a frame of reference for that, a 25-year-old will have a fairly robust stimulation of muscle protein synthesis with 15 grams of protein, where to get the same effect in a 65-year-old will require over 30 grams of protein. So, you have fewer calories and yet you need more protein.
- Mm-mm. You've highlighted so many connecting points between the immune system, our cardiovascular system, our metabolic health. So, when we see this loss of lean muscle, is that showing us some red flags or raising your index of suspicion that we need to look at other areas of the body? Maybe we need to be more aggressive in our glucose screening or really look at insulin resistance. How does that impact the way that we do precision and preventive medicine?
- Yeah, you know, I think as we get more precise, as we get more personalized, I think one of the things the research is totally clear on is that if you encounter someone with what we call metabolic syndrome or prediabetes that exhibits elevated fasting blood glucose, elevated triglycerides, lower HDL, all of those, you know, the abdominal obesity, all of those signs, those are carbohydrate problems. That means your carbohydrate to protein ratio is probably out of balance for your muscle health. And we've done studies and a lot of others in the last 20 years, there's a lot of studies that show that if you reduce your carbohydrate level down, the average American's eating 300 to 300 plus grams of carbohydrate per day. The RDA for carbohydrate, most people don't even recognize there is one, is 130 grams per day. So, we're eating three times our carbohydrate minimum needs. And so, if we reduce carbohydrate down below 140 grams per day, the research is pretty clear that you'll correct all of those metabolic syndrome characteristics within weeks, within 10 to 14 days actually.
- Wow. And is that true even for someone who might be 60 or 65?
- Yeah, we've personally done a lot of work with individuals in their 50s. Haven't done as much with people in their 70s. But there is some data there about that. I think it's true, but there's a lot less data on that specific topic into diabetes with older age groups.
- Sure. But it certainly makes sense to me when I think about it.
- Yeah. I see no reason why it wouldn't be true. And again, there's some data, but not nearly as much.
- Right. So, aging is a clear indication for an increase in dietary protein. As we look to personalize our nutritional recommendations, are there other signs or symptoms or other health states that would cause you to think, "Wow, this person really needs to increase their dietary protein."
- Yeah, I think we need to recognize, there's this belief in how we deal with protein right now. If you look at even the RDA, it's based on nitrogen balance. And my first question for that is, "Okay, what health outcome does that actually reflect?" Ha. Nothing. And so then, you know, my point, when people ask me, "Well, what's new in protein? What's coming in protein?" I say, well, we're going to realize we actually don't even have a protein requirement. We actually have a requirement for nine essential amino acids, and then additional non-specific nitrogen or amino acids non-essential. And when you start focusing on the nine essential amino acids, then you start seeing other outcomes. You see methionine and cysteine that relate to glutathione level. So now, we have the anti-inflammatory part of it. And what we know is that the amount of the methionine, cysteine, the sulfur amino acids that a 60-year-old needs is twice the amount that a 25-year-old needs to maintain their anti-inflammatory antioxidant level of glutathione. We know that threonine is primarily an amino acid used for gut mucin. And so, if your threonine level is low, your mucin protective level in the gut goes down. And we know gut health is important. We know leucine, the amino acid I study, takes two to three times the level in an older adult to stimulate muscle protein synthesis. So, I think the future is we're going to recognize that nitrogen balance is pretty relevant, but we have all these other things, you know? Muscle protein synthesis, thermogenesis, satiety, gut health. We know that phenylalanine, tyrosine directly relates to brain function and memory. So, there's just so many direct links of amino acids to health outcomes. And right at the moment, we're not measuring those very well.
- You know, for years in the functional medicine world, we've been talking about the importance of dietary protein for biotransformation and elimination and for healing, and if someone needs support with their intestinal barrier function. So, I just have to say, it's so validating to hear an expert like yourself say and recognize how important that is.
- Yeah, and I mean, we can go on the gut health. We know that glutamine is an important metabolite for gut health. We know that cystine is very important for gut health and the cystine bridges in terms of immune function. Threonine I just mentioned. So, people have just barely scratched the surface on thinking about these amino acid, you know, what's the optimum level of these amino acids for gut health? And how is it different in a 25-year-old versus a 65-year-old?
- Right. And when we think about the protein that we're eating, are there different protein needs for someone who's fine to just maintain their lean muscle mass versus someone who wants to experience muscle growth?
- (chuckles) So, you kind of touched on two different things there. In terms of the range of protein, we know that... I always have to stop and think about putting this in kilograms versus pounds, but you know, from a dietary guideline standpoint, we know that the minimum protein level is about 0.8 grams per kg, which is about 0.35 grams per pound. And it goes up to about 2.2 grams per kg or 1 gram per pound. So, that's kind of a big range there. We know that healthy young people can get along pretty well around that minimum number, you know? Because they're eating more calories, they're physically fit. As we get older, it's pretty clear that people need to be up around closer to that 0.75 grams per pound. So, about twice the RDA at this point. So, it's pretty clear that we need a higher protein amount, and specifically we need more essential amino acids. Our protein numbers are really driven by what does it take to get the essential amino acids we need. One of the things you could do is just eat a higher quality protein mix. So, if you had, let's say, 50% of your diet was plant-based when you're 25, when you're 65, if you drop that down to 5% and the rest came from, you'd get the same effect. So, the amount of protein's part of the question, but the quality of the protein also comes into play.
- So, when you talk about quality, are we talking bioavailability in terms of animal foods versus plant foods?
- So, the two factors in quality are both the essential amino acid content and also the bioavailability of those amino acids. So, amino acid content, animal proteins in general have about 45 to 50% of their content is essential amino acids. The human body's around 50 to 55%, so similar. Plant proteins range from about 25 to 40% essential amino acids. So, there's a lot less of them. And you know, I always make the point that plants don't have amino acids for humans. They have it for their own sake. So, leaves and roots and stems and seeds and flowers are kind of different than human body parts. And so, the quality of the amino acids is different. But then, also in thinking about the amino acids are there for the plants, 50% of them are bound to fiber. And as humans we can't digest the fiber very well, maybe a little bit in our colon, but we don't get amino acids if they're bound to fiber. And so, most plant proteins, whatever the number on the label, the facts panel, you probably only absorb about 60% of it. And the exception to that is isolated protein. So, if you're buying a soy protein isolate, that's probably around 95% absorbed. But if you're looking at wheat protein on your bread label, you're absorbing probably no more than 50% of it.
- I mean, this leads to my natural question of can we get this from food or do we need to supplement? Can we supplement? Is that a viable option? Can we get a protein powder? How are we going to get all this protein?
- Yes, yes, yes. Yeah, you know, so my earlier comment that as we get older we need fewer calories, so we have to be more concerned with the quality of that protein. And so, we can definitely get our essential amino acids. We can get, if you ate nothing but animal proteins, meats, and fish, and I put fish into that category. Meats and fish and eggs and dairy. You can get your essential amino acids with about 50 grams of protein per day, okay? Of animal, pure animal protein. So it's possible to do it, but it has to be carefully selected. If you need, if it's all plant protein, you probably will need more than at least double that. You may need 100 grams. Your question about supplements, I think that as we look at older individuals, I frequently use protein supplements because they have both the need for fewer calories. So, they can't eat as much food, but they also will develop problems with chewing. They'll develop problems with what can they eat? Can they eat enough protein? So, one of the things we often do and actually have developed is some of the protein shakes. We think that's a very important way to think about. We know that as you get older, getting enough protein into that first meal of the day is important. Protein distribution is something that my research group, Doug Paddon-Jones and I sort of developed. When you come out of that overnight fast, during that 12 hours you're sleeping at night, your body, and particularly your muscle is what we call catabolic. It's breaking down. Your muscles are supplying amino acids to the rest of the organs to keep them running all night long. And so, when you wake up in the morning, your body's very catabolic, and it will stay that way as an adult until you get enough essential amino acids in. And that requires around something over 30 grams of protein. So, a lot of people find that, well, gee, if I'm going to do that with eggs, or you know, that's a lot of eggs. That takes 5, 6, 7 eggs to do that. A lot of people don't want to eat meat for breakfast. A shake is a great way to do it. You can get a protein shake. It's in a liquid form. It's very easy for an older person. I had it with my parents as they aged all the time because they just didn't want to eat the amount of food or they had trouble with chewing some of the food. So, I think shakes or supplements are very good for older people. Do young people need it? You know, for the most part I think it's kind of a waste of money and less... But again, I use them all the time, but I probably qualify as older. But you know, I think it's an issue of convenience. Does the average American need a lot of supplements? Nah, probably not. But again, it's important to get the right amount of protein in the right time of the day.
- That makes good sense. I'm also thinking about our patients and maybe you have some advice, but my clinician brain is picturing all of these patients in whom I change their macronutrient distribution, less carbohydrate, more protein, and they tell me, "I am so full. I'm really having a hard time getting this all in because I'm just not hungry." What advice do you have for us?
- One, I think that is a great feeling. I think that is the issue in obesity management that we need to think about. And we always try to, we've done a lot of clinical research with weight loss and obesity, and we always try to front load the protein in the day. We want that first meal to be fairly high. So, we typically target 40 plus grams of protein and 400 calories in that first meal because we want them to say, "Wow, that's more food than I can eat." And you know, if you have someone who's struggling with obesity, who starts their day saying, "Wow, that's more food I can eat," that's a good sign. We also want them to never snack. One of the things that we've learned in research is that protein has a satiety effect, but it doesn't seem to make much difference on what you eat the next meal. We're social eaters and we kind of tend to eat what's set in front of us. And so, if it's 12 o'clock, you eat what you have. But what we find is that the higher protein tends to keep people from snacking between meals or after dinner at night. And I think that is the huge benefit to satiety of protein is it alters your feeling for, "Gee, I need a snack."
- Right, right. So are you, I mean, are you aligned with, my takeaway that if someone is eating more protein in the beginning of the day, and maybe at their normal lunchtime they say, "I'm not quite hungry yet," then you can wait until you're hungry.
- Yeah, it's interesting that we have hundreds and hundreds of papers about protein at the first meal. We have a fair number of papers of protein at the dinner meal. And we have essentially zero papers, research studies at lunch. (laughs) And so, some of the research that we have done, people have interpreted as, "Well, you need an even distribution all day long." I actually don't think that's true. And to your point, I think that for most people, your midday meal should be one aimed at controlling your calories. What do you really need? Don't eat because it says it's 12 o'clock, eat because of your calorie need and your protein. So, the lunch meal adds up to part of your protein per day. But I don't think there's anything particularly magical about it. The one exception I would give to that is, if you're looking to use protein to regulate your carbohydrates, like in Type 2 diabetes, then the even distribution makes sense because you're trying to very carefully manage that carbohydrate-to-protein ratio. And so, an even distribution makes sense. But for people who are not struggling with glucose regulation, I think the, and frankly, I often skip the middle meal. I'll pay attention to the first and last one and lunch is whatever I decide it to be. (laughs)
- Yeah, okay, so it's breakfast where the metabolic magic is really happening.
- We have, like I said, hundreds of studies that that is the most sensitive meal for muscle metabolism, moreso in adults than it is in kids. We know that a child will respond to grow. So, there's a regulation and you know, I'll talk to it about it at the meeting in a more detail, but there's a regulation we kind of discovered called mTOR. And that regulation has multiple inputs. It's a major regulation of muscle protein synthesis, but there are at least three different inputs, one of which is hormones. And so, as a growing child or a young adult, this system is heavily regulated by hormones. You're very efficient with protein because hormones are on your side. But as you get beyond growth period, as you get into your 30s, hormones no longer have much of a benefit for muscle protein synthesis. They're almost non-existent. And now, the regulation shifts to quality of protein and exercise. And so now, how you balance those determines how your muscles will respond. And what people don't, people think about growth and say, "Well, protein's important for growth," but our net accumulation of protein from growth is only about five grams per day. It's really low. But for you and I and a 75-year-old, 16 or 65, we have to build 250 to 300 grams of new protein every day for what's referred to as repair and remodeling. And so, we're constantly turning over every protein in our body. I like to remind people that that rate of protein turnover, we rebuild the equivalent of our body's protein four times every year. And how well you do that is the definition of aging. So, when you see people who have falls and hip fractures, you see people who are frail, see people with poor skin quality or poor hair quality, those are all signs of protein deficiency.
- Well, that was very motivating. I'll definitely think about this when I'm eating breakfast tomorrow morning. (Donald laughs) Sometimes patients will ask me, "You know, I'm always aiming for this 30 grams at least of protein in the morning." And they'll say, "Okay, I feel like I can eat a couple eggs, but if I put some collagen peptides in my coffee, does that count towards my protein requirement?" What do you say?
- Well, collagen is probably the single worst protein you could ever come up with because it is deficient or limiting in five of the nine essential amino acids. So, we have to really think about collagen.
- Yeah.
- I personally think it's lousy, but I've had enough testimonial data over the years to realize there's gotta be something going on. So, let me help your listeners think about how to consider protein. As I said at the beginning, we don't really need protein at all. We need nine essential amino acids and non-specific nitrogen. Okay, so if you meet your essential amino acids with good protein, adding collagen on top of that provides nitrogen. Even though the amino acids are crappy, it allows you to get that extra nitrogen, the body can then make the non-essential amino acids out of. So, I think that adding collagen, whether it's 10 grams or 40 grams into your day, if you're eating 100 grams of regular protein and you add collagen on top of it, that's going to work out fine. If you're only eating 50 grams of protein and 20 of it comes from collagen, you're going to be deficient. So, the collagen story depends on how much other protein, because it's frankly a lousy protein, but there's evidence that it has some effect on skin or nails or whatever. Is that because of its glycine content or its arginine content? Maybe. People say, "Well, it has hydroxyproline." People need to understand that hydroxy, once it amino acid's hydroxylated, it can never be used in the body again. So, those aren't the answers. Hydroxylysine, hydroxyproline, those are useless to the body. So, those can't be the answer. Glycine, arginine, perhaps.
- Right. I mean this really goes back to the discussion about quality that you spoke about.
- Exactly.
- It's really getting those essential amino acids. And if those basic needs are met, okay, then you can add-on some extras that make you feel good.
- Sure. Right. And you know, if people get 50, 60% of their proteins from animal proteins having beans and nuts and you know, other plant proteins along with it are great. But if you eliminate animal proteins at all altogether, become totally vegan, it's almost impossible to get your essential amino acid content. And while a 20-year-old might be able to pull it off, because they can eat 3,000 calories, a 75-year-old can't eat enough to get to it.
- You talked about-
- Without supplements. I'm sorry.
- Right.
- Yeah, I mean, they would almost have to go to isolated proteins, and that's functional.
- Okay, well, you spoke about the actually stunning protein requirements just to keep us at our baseline function. So, let's say then we add some weight training on top of that, we become a runner. How does that influence the protein that we'll need to consume to kind of maintain those just baseline metabolic processes?
- Yeah, again, a little more complicated than you might hope. (host giggles) And you know, easier to talk at the meeting than it is necessarily on a podcast. But one of the things I'd like the people to think about is the protein needs relative to exercise is a U-shaped curve. So, we think about athletes needing more protein. We think about bodybuilders needing more because of mass, a little bit. You mentioned runners. What we know is that aerobic exercise, running burns about 10 grams of amino acids per hour. So, there's definitely a higher need with exercise. But at the other end of the curve, back to that mTOR story, there's an interaction between protein and exercise. Exercise actually potentiates the system. It makes it more sensitive to the amino acids you're eating. And so, people who are totally sedentary actually need more protein than somebody who's somewhat physically active. So, being moderately physically active actually makes your body more sensitive to the protein you're eating. So, the worst of all worlds would be a 65, 70-year-old person who chooses to be sedentary and is overweight because we know all of those things decrease your efficiency of protein use. That's probably the definition of the person who needs the most protein.
- Wow! That is a fact I'm going to have to come back to again and again because how very interesting. I think many of us have it in our minds, oh, if you're doing any amount of exercise, you need to eat exponentially more protein to get a benefit.
- Yeah, from a muscle standpoint we know, there's a lot of research looking at muscle protein synthesis in both younger and older individuals. And we know that the muscle effect plateaus out at around 0.7 grams per kg. I'm sorry, 0.75 grams per pound. About 1.8 grams per kg. Sorry to confuse everybody. But you'll see a lot of athletes eating at least one gram per pound. I don't have any problem with that. But the research is pretty clear. There's no detectable difference in muscle protein synthesis between about 1.6 to 1.8 grams per kg up to 2.2. There's no detectable difference. There's a big difference between 1, 1.2 to the 1.8 or 2.2. There's a big jump there, but going from one point... So, most of the exercise literature says that athletes should get up to about 1.8, which is about 0.85 grams per pound. But beyond that, there's no real benefit.
- I see.
- To muscle. Again, we've been mentioning this ratio to carbohydrates though. But again, if somebody has a glycemic problem, going up to higher protein, so you can lower the carbohydrates may be very beneficial. So again, we need to separate out the issue of just muscle protein synthesis. That's specific measurement versus metabolic regulation.
- Right. Right. Well, as a clinician who, in the clinic patients are asking me, "Do you think I'm eating enough protein?" And you know, I can do a diet recall and I can crunch the numbers and look at the grams of protein that they're eating. And you know, maybe they're eating a 100, 120, 150 grams of protein every day. And I can make some guesses. But are there some things, other things you're looking at, I imagine glucose control, you know, a fasting insulin. What are the things you're looking at to give you confidence that this person is eating adequate protein?
- Yeah, that's a great question. Because the protein outcomes in general take a long time to manifest, you know?
- Yeah.
- If you're thinking about muscle mass, you're probably going to have to track that for at least four months to be able to pick up a difference, you know?
- Okay.
- The methods we use of body composition aren't going to pick it up. I see people say, "Well, I ran a higher 1.5 grams per kg versus 1 gram per kg. And after 10 weeks I didn't see a difference." Well, of course, you didn't. There's an old adage in nutrition research that if you design a bad enough study, it's easy to see no difference. (both laughs) And so, I think you have to really think about that. If you're looking at the issue of metabolic regulation, glucose-protein ratio, we find the best marker is triglycerides.
- I see.
- If I take anyone, you or I, presumably we both have normal triglycerides and I put us on, depending on what you're eating. If I drop your glucose per day, your carbohydrate per day below 140, we'll see a 20% drop in triglycerides no matter where you start from. 20% drop. That is so consistent, we use it as a biomarker for compliance. So, we'll have people on diets and we'll get their initial measurement, put them on a lower carb diet. You'll see this drop in triglycerides and another, next month they come back in and their triglycerides are back up. We know they're not following the diet. I mean, it is that specific. So, we can do things moment to moment. Most people we can't measure protein synthesis in, so you can't really follow that. It's really kind of hard to track, you know? Is that protein a benefit in short-term outcomes? One of the things that we pretty consistently see in people though, probably the two things that are most common as we get back is, oh my, my skin or my hair is different. I just noticed it's got better texture. I don't look as wrinkled or whatever. But the other one we find is people will say, "You know, my weight hasn't really changed, but my clothes all fit different." And those are probably the most obvious things that you can't really quantitate very well. But the comments we hear back that tell us people are following it.
- Right. Okay.
- And the other one is snacking. If we hear people coming in say, "Yeah, doc, I'm following it, but I'm always hungry," or "Yeah, I'm craving X or Y or whatever." That's another hint that they're not following the diets.
- So, satiety, body composition, triglycerides. We had another guest on the show at some point who said, "You know, everybody has worn a continuous glucose monitor at this point. When are we going to invent a triglyceride monitor?
- Yeah, yeah.
- That over time will just tell you immediately how you're responding.
- You know, I think this is straying a little bit, but I think glucose monitors and A1C may not mean the same with higher protein diets. I think one of the things we're seeing with carnivore diets, if you think what about A1C means, is it the average of glucose per day or is it the glucose excursions after the meal? The research tends to say it's the glucose excursions after a meal. And from a physiological standpoint, that makes sense because high glucose has an osmotic effect that damages every cell in the body, from your eyes to your kidneys, to whatever. So, those high glucose excursions, when you get up to 140, 160 milligrams per deciliter, those cause damage. But when you go to a low carb, higher protein diet, what you see is that your fasting levels stay higher. And so now what you have is a very, because of gluconeogenesis. What you now have is around the clock 24 hours a day, your blood glucose stays a little, it stays very constant, but it doesn't go through the big peaks and valleys. And so, I don't know that I believe that an A1C of 5.8 means the same in a high carbohydrate diet as it does in a low carbohydrate diet.
- Okay. This is fascinating. I will need another hour of your time at some point just to talk about that. But I imagine, if someone's glucose is a little bit higher but stable, they'll feel better. They'll feel more stable, right?
- Yeah, yeah, yeah. I mean, what we have seen in animal studies, we've done a lot of animal studies too, where my lab is really a basic biochemistry lab by training. What we see is that muscle consistently using glucose 24 hours a day on a low carb, higher protein diet. Where what you see on a high carb, low protein diet is these huge swings that during the middle of the night, high carb diets have to rely heavily on liver glycogen to keep blood glucose stable. And even then, they'll wake up with fasting blood glucose in the 70s, where a person on a low carb, higher protein diet will wake up with blood glucoses in the upper 80s. It's because they're relying on protein metabolism at 24 hours a day as opposed to glycogen. They'll wake up with their glycogen levels fully full in the morning. They haven't used them. Where a high carb diet person will use at least 50% overnight.
- Mm-mm. Right. It's very compelling, the need for more protein. I think we're all compelled to go have high protein meal after this. Can we get too much? I mean, who's at risk for eating too much protein? Is that a thing?
- No.
- No.
- (chuckles) Simple no. So we've had, I mean, we've had people wanting to say it's bad for your kidneys or bad for your bones, or, oh wow, protein causes cancer. All of that is really nonsense. The kidney thing comes from diabetes. And we know that if you have advanced renal failure, that you're going to have to reduce solutes in your diet, whether it's salts or whether it's urea. And so, the question there though becomes at what point should you make any adjustments? We know that if you shift from a higher protein diet to a lower protein diet, you will shrink the size of the kidney. You will shrink your glomerular filtration capacity. And so, if you're already having filtration rate problems and you shrink the size of the kidney, you're going to accelerate that. So, at some point in kidney failure, you need to make an adjustment, but is that stage three, stage four? And I think that's a viable debate. And I don't know, I'm not a renal specialist, but I've talked to a lot of them, and I think it's a pretty active debate. And obviously when you get to renal failure, then you have to go to dialysis and you increase your protein back up again. So, when the Institute of Medicine looked at that issue, they said there's no evidence that higher protein causes renal damage. In fact, low protein, which shrinks your kidney size, actually is a bigger risk.
- Okay, so for most people, they're eating protein, they feel really satisfied. They're likely not going to overeat protein?
- Yeah. I mean, and I were talking about satiety, you know? And the example I like to use is that you go out for dinner, you've had a nice steak and you get to the end of the meal, very few waiters will come around and ask you if you want another steak, but most people will ask whether you want chocolate cake. And I don't know if I've ever seen anybody eat another steak at that point because it's a, you know, it's sort of like, wow, I can't get through that one. So, you know, it just says, we can overeat carbs, but it's impossible to overeat protein. We find in our, we've done a lot of research with women and weight loss. We find that our target level is typically around 120, 130 grams per day. We find it is enormously difficult to keep women above 100 grams a day. They just don't want to eat it. And we find that they will lose most of the metabolic benefits if they drop down to 90. So, there seems to be a real threshold for metabolic benefit around a hundred. Again, for women, midlife women that we've studied. A real threshold around a hundred grams per day for metabolic benefits.
- Wonderful. I'll just share, I've been tracking my own protein intake just to see, just for curiosity's sake, and I feel very confident getting adequate protein does not happen on accident.
- Yeah.
- I mean, you really have to be intentional or it doesn't happen, at least for me.
- Yeah, I'm a protein expert as most people would agree and I find it really challenging to keep my intake at 120 grams per day, you know?
- Yeah.
- It's a real challenge. And I'm a world expert in where to get protein. (laughs)
- It takes planning and some-
- It does.
- Intentions certainly.
- Yeah. Yeah, yeah. You really have to think about, particularly the first meal. We always, when we teach it, we always start with saying, "You know, your dinner's pretty much okay. We're not going to do much to it. We don't want you to think too much. We want you to control your carbs at dinner." But we're going to focus on how do you get your breakfast? How do you consistently get that first meal to 35 to 40 grams? That's the challenge. And if you can get people over that hump, you know, can they learn to do some sort of a breakfast sandwich or some sort of eggs and vegetables or some sort of a shake that fits into their lifestyle? We think that is the first step in being successful with this.
- Well, there's just so many insights and so many things that we can do in the clinic to improve so many aspects of our patient's health. And we know that you'll be taking a deeper dive into this at IFM's Annual International Conference, which is happening in May. We're so excited to just have this little preview. But will you give us a little sneak peek of what attendees will be able to learn from your presentation at AIC?
- I think we're going to go into a deeper dive of sort of everything we've talked about. You know, I'm going to go into the concepts of carbohydrate tolerance and meal threshold. I'm going to go into concepts of protein quality. I'll talk a little about our research with sort of the mTOR leucine story in depth. And I'm going to finish up with just sort of highlighting, when we put this all together in a weight loss study, we published the first study that actually looked at the synergy between protein and resistance exercise for changes in body composition during weight loss. So, I'm going to use that sort of as a model to say, show people that when we put this all together, these are the benefits you can see. And I think it has a lot of implications for things like the drugs, the GLP-1s. What is the rate of weight loss you should look at and how does that affect your long-term health? So anyway, that's the goal. We should have fun covering it.
- It's going to be an excellent presentation, and we can't wait to hear more. In terms of today's episode, for everyone who's listening, what takeaway do you want our listeners, they tune in, they log off, what do you want them to take with them after listening to this conversation?
- Get protein into your first meal. And everyone eats too much wheat. Everyone eats too many grains. You have absolutely zero nutritional requirement for grains in your diet, other than they provide calories. If people can get their grains under control, we'll solve a lot of the issues of obesity in the United States.
- Well, I hope people tag us in their protein rich breakfast so we can see what they're eating. Dr. Layman, thank you so much for sharing this time with us today and all of these clinical insights. It's really been a pleasure learning from you, and we are so looking forward to hearing more from you at the Annual International Conference.
- Well, thank you. It was great to chat with you. And I'm looking forward to the conference also.
- See you next time, everyone. (gentle rhythmic music) Discover the latest research and innovative clinical practices at IFM's Annual International Conference. For more information, visit aic.ifm.org. (gentle rhythmic music)