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Unlocking Protein’s Power | Dr. Jess Gwin on Essential Amino Acids and Muscle Health

Episode 98, duration 1 hr 18 mins
Episode 98

Unlocking Protein’s Power | Dr. Jess Gwin on Essential Amino Acids and Muscle Health

Dr. Jess Gwin, a recognized expert in nutritional sciences, unveils the profound role of proteins and essential amino acids in our diet. We discuss the critical importance of protein quality and its impact on more than just muscle health—exploring how it influences hunger, brain function, and satiety.

Delving into the nuances of daily protein optimization, Dr. Gwin explains why all proteins aren't created equal and the implications for dietary guidelines. The conversation also covers the limitations of current dietary guidelines and what future research is needed to improve public health recommendations.

Dr. Gwin provides insightful perspectives on the potential changes in how we view protein intake and its overall role in our health.

Join us in this enlightening podcast where we explore the essential yet often overlooked aspects of nutritional science and how it impacts your overall wellbeing.

Unlocking Protein's Power - Dr. Jess Gwin on Essential Amino Acids and Muscle Health

In this episode we discuss:
– The critical importance of protein quality
– Impact on more than just muscle health
– Exploring how it influences hunger, brain function, and satiety

00:00:00 – Meet Dr. Jess Gwen: Insights on Dietary Patterns and Muscle Physiology

00:06:26 – The Role of Protein in Appetite Control and Weight Management

00:12:50 – Understanding Protein Quality and Dietary Guidelines

00:19:14 – Essential Amino Acids: Impact on Health and Nutrition Plans

00:26:00 – Optimizing Diets with Essential Amino Acid Density Scores

00:32:51 – Sports Nutrition and Recovery: The Role of Essential Amino Acids

00:39:24 – Challenges of Implementing Protein Recommendations in Practice

00:45:41 – Metabolic Differences Between Animal-Based and Plant-Based Proteins

00:52:30 – Aging, Anabolic Resistance, and Protein Needs

00:59:00 – Research Gaps in Protein Quality and Essential Amino Acid Density

01:05:36 – Protein’s Role in Satiety and Appetite Control

01:12:12 – Future Directions for Nutrition Science and Dietary Guidelines



 Dr. Jess Gwynn, welcome to the podcast. I am really excited to have this conversation. You are a whiz on all things protein, essential amino acids. And I first heard about you through our mutual friend, Dr. Nick Behringer, Ranger dietitian. Welcome to the show. Thank you. I’m so excited to be here. I love talking about all things protein. It’s really been a huge part of my life for the past decade. So it’s a pleasure to be here. Thank you. Yes, certainly. And I would love for you to catch us up to speed. I know that you have worked very closely with someone named Dr. Heather Leidy. She is truly extraordinary in her work. The contribution of her work really is, I mean, it’s multifactorial, but really this idea of protein, protein first, protein effect on the brain. But before we talk about all that, just catch us up to speed a little bit about where you’ve come from and what you’re doing. Absolutely. So I’ll just start from the beginning and the origin story really does start with Heather. But a few years before that, I really found this interest in nutrition and exercise science. I was a former athlete at the University of Missouri. And at that time, I was really just interested in how do I improve my performance. So naturally coursework aligned with that quite well. So fast forward through undergrad and I reached that time where you’re transitioning out of your undergrad studies and trying to really pursue a next step. And there became an opportunity to become a lab technician at the University of Missouri in their nutrition and exercise physiology department. There was a really unique opportunity because that department pairs both nutrition and physical activity. They really understand at that time that they were the king and queen, kind of this health perspective. And happened to be that Heather had an opening as a lab technician. So I really got my start in this research space from the ground up, learning how to build participant folders and paperwork, etc. And that love for research kind of grew over that next 10 months, where she allowed me to get really involved in her day to day full feed intervention studies. At that time, we were working a lot with middle aged women, looking at appetite control and satiety. So eating behaviors, for those of you unfamiliar, that’s hunger, fullness, feelings of food reward, how full are you and when do you stop eating a meal. And so her work really has focused on across the breadth of her career, using dietary protein in healthful interventions

 to improve appetite control and weight management. From there, I fell in love with the research process and decided I wanted to pursue a PhD in nutritional sciences and had the extraordinary opportunity to stay on in her laboratory. And we really just over the next four years continue to focus on those full feed interventions, using high quality proteins and really trying to better understand how consuming high quality protein across the day and across different meals may impact an individual’s appetite response. It included questions of subjective nature, where we asked an individual what’s your immediate feeling of response or immediate feeling of hunger or fullness. But we also looked at the blood work, looking at circulating markers of hunger and fullness through hormones that are derived from the gut and feedback into the brain. We also did some functional brain imaging at that time, kind of trying to pair this subjective measure of how does someone feel, how is their body responding, and then what does that look like in the brain’s response. And so we use pictures, for example, of animals and foods. Both are really rewarding and pleasurable, but when an individual is in a functional MRI scan and you show them a picture of food, there is an area of their brain that is associated with hunger and fullness, food reward, that lights up or doesn’t light up. And so we were testing whether the manipulation of protein impacted that food reward region of the brain. And so that was really the basis of the first two projects of my doctoral training. And then the third, I was really interested in this concept of marrying dietary interventions and how they impact sleep. And so my third project, we did look at whether consuming breakfast, particularly one rich in protein, had any relationship to sleep quality. And during that time, it was a doctoral study, we were bringing it onto the lab, it was a new technique for us, but it was really rewarding opportunity to start working with cross-translational teams, including sleep physiologists, to better understand this global picture of nutrition, impacting sleep, and overall the behavior and lifestyle of an individual. So after that, so that was we ended at Purdue University. I had a great opportunity. And you went with Heather. Heather wasn’t, she was in Arkansas, right? University of Missouri. And then I did skip over the transition to Purdue University at that time. And the fun that we had with standing up a new lab, that was in the midst of my four years with her. But nevertheless, it was an exceptional experience to move with her and have that opportunity to stay on. And where are you now? So now I am at the US Army Research Institute of Environmental Medicine. We are located just west of Boston in Massachusetts.

 And I’ve come here by way of postdoc opportunity, postdoctoral training, under the mentorship of Dr. Stefan Paciacos. So I’m 20. By the way, amazing. And just took a position at the NIH as the head of, is it dietary supplements? Yes. What is the official title? Yes, he is the director of the office in the Office of Dietary Supplements. And just for the listener, the reason I wanted Jess on is because her pedigree is fantastic. And there are a lot of nuances in the domain of nutrition, specifically in protein, because protein acts as a signaling molecule. And again, I say the word protein, as if it’s one thing, it is this multitude of amino acids. And what I really want to get into, Jess, is we talk about, and in this space, protein is often thought about muscle. This distribution question is really, are we going to change body composition? How is it stimulating muscle protein synthesis? But your work really highlights the other aspects of protein ingestion. And what I found so fascinating about some of the work that you were involved in is the dosing response to hunger. Let’s put skeletal muscle aside. The dosing response to hunger to be able to leverage a certain dosing of protein to mitigate hunger and allow individuals to ultimately follow a nutrition plan with the outcomes of a better body composition. So I would love to hear a little bit about the work that you are doing, have done, where we can think about some of the limitations of the current dietary guidelines specifically around protein quality and go from there. – Absolutely. We can talk about the dietary guidelines for America. And for those of you that don’t know, this is a framework for policymakers, nutrition professionals, as well as health professionals. And they’re really intended to make practical recommendations for a nutritionally adequate diet. And as you said, Gabriel, essential amino acids and dietary protein quality is something we’re very interested in in our laboratory, as well as my mentors laboratories. And what you can really discover in the dietary guidelines if you dig in when you’re focused on protein is a lack of addressing dietary protein quality. And you might ask for the listeners, what is protein quality? Well, when we consider protein quality, this is the amino acid composition, specifically the content of essential amino acids. And I know your listeners, if they’ve been following for some time now, they’re aware that essential amino acids are the amino acids or the building blocks of protein that the body cannot make, which means we have to get those essential amino acids from dietary sources. And now we’re starting to build this storyline of, okay, it’s needed in the diet, it’s required. It means it’s really a key component of achieving an adequate diet. Or if you’re more in the realm of pursuing optimized diets, you really need essential amino acids at a higher level to achieve a more optimal diet. And so we dug in and found that the dietary guidelines aren’t really addressing per se this protein quality perspective. And this could be for a lot of reasons. This could be because we have had limited ability to measure essential amino acids in food sources for everyday consumers. For example, if you look at the food label, we don’t have a great way of demonstrating right now the amount of protein from a quality perspective on a food label. Can you clarify that for the listener? Because what they’re thinking is they’re thinking, what do you mean? I see protein on the back of a label. And it says, for example, if you see a hemp protein shake, you will see 15 grams of protein on that. And what I’m hearing you say that, yes, it is saying that it has that protein in, but it does not speak to the quality. Right, right. So the quality really, again, is the content of amino acids, the profile of the amino acids in the bioavailability. What that label is telling you is the nitrogen content. So that protein gram amount doesn’t speak to the essential amino acid content and it doesn’t speak to the source. And so it’s really a good starting point for trying to achieve quantity and intake, but it really doesn’t give the consumer a transparent view of the quality of the protein. It’s very misleading, essentially. We have some growth that we can make. We said that very diplomatically. I would agree. So in the dietary guidelines, they have pursued one way to provide recommendations for protein intake. And this has come about as an ounce equivalence. And for example, an ounce equivalence in the dietary guidelines for nuts is half an ounce. As the name would imply, the equivalent of that in lean beef is an ounce. However, the problem when you start to look at the amount of protein that ounce equivalence provides, it’s only around four grams of protein in the nut amount and nine grams of protein in a lean cooked beef portion. When we break it down even further into that essential amino acid content, it’s only about one gram of essential amino acids in the one half an ounce of nuts. Whereas in the equivalent to the dietary guidelines equivalent to lean beef, it’s about 3.5 grams of essential amino acids. So now as the listeners are hearing, okay, so there’s a proposed ounce equivalence, but what does that mean from a protein perspective? And that’s really where in this review, we were trying to go with this commentary of bringing to light a discussion of certainly there was a reason for identifying an ounce equivalence at one time. And we have an evolution of nutrition throughout the dietary guidelines over the years. And it served a purpose at one time, but moving forward, how does this messaging for ounce equivalence affect an individual’s protein intake? And so we then pivoted a little bit to first build a case for physiological outcomes. And what I mean by physiological outcomes in particular whole body protein turnover. And at the time, Dr. Park out of Dr. Robert Wolf’s lab at the University of Arkansas for Medical Sciences had just published a paper looking at this very thing of ounce equivalence in the dietary guidelines in which they compared a half an ounce of nuts to one ounce of cooked lean beef. They went through every single comparison

 that are presented in the dietary guidelines, and they did a whole body protein turnover assessment. I’m sure many of your listeners have heard already how they do this, that you stabilize isotope tracers in which they model how amino acids are moving through the body. And what they showed is that as one might predict based on the quality and quantity of protein within the ounce equivalence, the animal protein sources, which typically score much higher for higher protein quality scores, produce a greater whole body protein balance. And so now we’re starting to build a case that these ounce equivalence don’t present physiological equivalence. So maybe we go back to the drawing board and start to consider ways forward. But before I do that, to mention one way forward that our group came up with, I’m going to switch a little bit again that work with Dr. Nancy Rodriguez. She had a great graduate student that was pursuing understanding of how the omnivore healthy US eating pattern presented in the dietary guidelines starts to get modeled out. She was also interested in vegetarian patterns as well as vegan patterns. And what she did was model each of these presented patterns from the dietary guidelines and took a look at their overall protein quantities and central amino acid quantities. And when she looked at that, she started to see that, okay, if an individual who’s trying to, or a health professional who’s trying to work with an individual and design a meal pattern truly follows the dietary guidelines patterns presented and incorporates the ounce equivalence models, then you do result with an

 non-equivalence outcome. So the vegan versus the omnivore pattern, and you’re probably predicting a theme here or seeing a theme here, did not include the same amount of protein. And it did not include the same amount of total essential amino acids. And so through that modeling, that paper came out and it was a nice job of really highlighting in application, if we take a theoretical pattern and we put it into action, these are the actual protein intakes and essential amino acid intakes that these individuals are consuming. One important note, she did do her modeling based off of a middle-aged woman at 51 years old who was sedentary. And that’s important to note because now we’re starting to consider aging, this individual is moving into a later age, their caloric intake is starting to become lower, the caloric needs are lower. And so for that modeling, there is a cap on the total caloric intake. And one of the other take-home messages is that the individual had to consume more total energy in order to meet those protein intake requirements. So I’ll just take a pause there and know that was a lot. And any more of that you even want to unpack? Well, I think you said a few things that are very important. Actually, everything that you said was very important. And the idea is that the US dietary guidelines for Americans was created to function as, again, guidelines for healthcare professionals, for individuals also trying to be able to implement what we would consider a diet that was sufficient to meet baseline needs. Again, these are ways in which we can design a diet to overcome a deficiency. Not discussing any kind of optimization, there is not a differentiation for an aging population, which we know you had mentioned muscle protein turnover, whole body muscle protein turnover, you guys can listen to one of the episodes that actually I had Dr. Bob Wolf on from Arkansas. He discussed these stable isotope tracers, as well as Don Lehman. It’s just a way of being able to see the movement again of these amino acids in the body. But what becomes really important is that

 right now the dietary guidelines and the recommended dietary allowance, which is 0.8 grams per kg of protein, does not differentiate the quality of protein. And I think one of the reasons why I really want to Jess to come on here is number one, she’s a neutral party. Jess cares about the science and is not encumbered by the information on the internet from influencers. She is purely a scientist. Jess, is that fair to say? That’s definitely fair to say. In fact, I don’t even know if Jess has an Instagram account, but nonetheless, her science is phenomenal. And when we think about what we’re looking for for health outcomes, it becomes really important to recognize where the deficits are with the information that we’re giving and also a pathway forward. Right now, we are hearing about plant-based patterns. And it’s really important to note that could you overcome the amino acid deficiencies that would be put into place with the minimum requirements at 0.8 grams per kg? Yes. What Jess is saying to state it very simply is that it requires more calories and also typically more carbohydrates that ride along with these whole foods. And one thing I would even add to that is it takes more understanding from a nutrition education perspective, where really oftentimes a nutritional professional has to be involved to design these diets so that an individual, if they’re consuming a lower quality protein, this is more likely a plant-based protein, they need to be consuming complementary essential amino acids to achieve, as you said, those basic requirements. And so that’s another key point that Dr. Rodriguez brought out in her paper as well, that these diets they put together and were able to achieve the modeling with were done by registered dieticians with intimate knowledge of protein quality. So to your point, absolutely. Its total caloric intake has to be higher. Carbohydrate intake is higher. And nutrition education has to be higher.

 And we’re discussing protein. But as you had mentioned before, there are other nutrients that ride along. And you had just mentioned it in passing, but there are other nutrients. Again, it’s designing a diet, a full diet, which goes above and beyond protein for optimal health and preventing deficiencies. The conversation, while we discuss it as protein, because protein is easy, it’s a macronutrient that we eat. We don’t typically think about B12, zinc, selenium, anserine, creatine, a lot of these other low molecular weight molecules that ride along with these higher quality proteins. I would love for you, if you have a translatable way in which an individual is designing or deciding to reduce their animal based products, would a use of an essential amino acid mix be helpful? Do you think that there is a place for branched chain amino acids? And if so, how would you put that into a nutrition plan? Right, right. So I’ll preface as well. I’m not a registered dietician. So certainly this is just my scientific opinion, based on the current literature, as well as just thinking about the practical application of an individual trying to build a sustainable meal pattern. So with that, I definitely think Whole Foods approach. I’ve heard that on your podcast before. So Whole Foods definitely have a lot of benefits from their matrix. And what I mean by matrix is exactly what you just described. All of those micronutrients and vitamins that come along, because certainly protein is not the only macronutrient, so it doesn’t cover the micronutrients and vitamins as well. So for individuals who have the energy allowance in their diet, pursuing a Whole Foods approach would be most ideal.

 But as you mentioned, in some cases, individuals can’t consume enough protein to maintain, from a plant based source, to maintain that energy balance or that weight maintenance status. And so in that case, for an individual, and we bring this point out as well in this paper, in this paper, as well as Dr. Rodriguez does, using an isolated plant based protein powder could be one option. Freeform essential amino acids could be another option. These we’d like to talk about as tools in the toolbox. And I’m not going to pivot too much to our service members right now, but there are times in the military setting where you can’t eat a Whole Foods because of the logistics. And so same thing for an individual who’s jumping in the car, they’re trying to get their kids to work or kids to school on time. Maybe in that case, in a central amino acid powder that they can consume on the go helps them get to that more optimal intake. So to to have a short answer, yes, I think they have a place in the dietary pattern. And a level deeper is, do you envision integrating the essential amino acid density guidance into the existing dietary recommendations?

 Right. So I didn’t explain the essential amino acid density score earlier, but for the listeners, in short, really, this was a concept to consider the grams of essential amino acids in ratio to the total caloric intake of that meal or of that food. And by doing this, you could arrive at a perspective of a greater essential amino acid content per calorie. And so then for certain foods, you could have a score. And for example, a score of above 2.2 for an entire meal would score very high, meaning that the essential amino acid ratio to calories is very close to even. Right. Or what’s the max score? So we did not propose a max score. I think that’s where this concept was in its infancy. Certainly, we’re just trying to expand and explore of potential options. We don’t want to call out a concern without trying to provide one solution as we move forward. That’s very helpful. And you do feel that there is certainly a place for this essential amino acid

 density conversation, because again, unless it’s challenging, it’s challenging this idea. And then the next question above and beyond, I know this isn’t a list of our questions, but I’ll just mention it that there are essential amino acids and then there are limiting essential amino acids, like leucine, lysine, and methionine, which the leucine limitations, if an individual doesn’t have enough leucine, the outcome is relatively clear. Leucine is a trigger for skeletal muscle. It does other things in the body, but its primary role or one of its primary roles is, again, stimulating skeletal muscle. Methionine has its own role. And lysine, which has a longer pool, I don’t want to say half-life, but it seems like the protein turnover or the pools of lysine seem to last a bit longer. Would there be any issue having a lower amount of lysine? I think that that particular outcome and certain essential amino acid outcomes maybe become tricky for us to identify in an aging population. And it’s probably a deficiency or suboptimal intake over time. Again, this is just my theory that I’m mentioning. But one of the questions that I do have for you is I would love, because I know that we’re going to talk about muscle,

 I would love for you to explain the significance of protein quality on maintaining the health of skeletal muscle and just supporting overall tissues. Absolutely. So this has brought us to my postdoctoral work, which again was in Dr. Stefan Paciakos’ laboratory. And we had the great opportunity to continue collaborating with Dr. Arnie Ferrando and Dr. Robert Wolf and David Church down at the University of Arkansas for Medical Sciences. So this project and this concept of essential amino acid effects on muscle really came from, as you mentioned, this concept of maintaining muscle. And certainly you’ve had other scientists on the podcast discussing stress and catabolic crisis during aging. For our service members and our population of focus, we’re focused on the catabolic stress of energy deficits. And these energy deficits occur because

 there’s an increase in physical activity for a service member and oftentimes an inability to match that exercise with food intake. And the reason why I’m going into the weeds a little bit with kind of setting the stage here is that when an individual is in an energy deficit, the body starts to break down muscle and break down, and the body starts to break down muscle, which then causes an increase in essential amino acids as well as other amino acids in circulation so that they can be used for protein synthesis at other organs and in other tissues. It also may be that the body’s breaking down muscle in order to provide amino acids that get converted and oxidized for energy. And so as you mentioned, essential amino acids are very important for maintaining muscle health and even more important during energy deficits. And this is because of that increase in muscle breakdown and oxidation of amino acids for energy. And so really we’re interested in understanding if current sports nutrition recommendations for recovery from exercise and think about this. So the service member is going out and they’re performing their duties. They are running a mission and they’re exercising heavily. And during that time, they also need to recover. And so from a protein or an essential amino acid perspective, feeding them essential amino acids was one potential way to provide an optimal recovery nutrition intervention.

 But the starting point was do current sports nutrition recommendations apply in those extreme stress scenarios? And so we brought that back to the laboratory and tested a dose response, if you will. It was really a high dose versus a low dose, so perhaps not a true dose response. But the standard or the lower dose was the current sports nutrition recommendations of 0.1 gram per kg of body weight of essential amino acids compared to a higher amount, which was 0.3 grams per kg of body weight of essential amino acids. And what we demonstrated in this study is that following a controlled laboratory exercise and following five days of energy deficit at around 30 percent, individuals who consumed the higher dose, because this was a within subjects comparison and for the listeners that means the volunteers went through both the high dose and the standard dose. For the high dose, whole body protein net balance, which we didn’t define that yet today, but whole body net protein balance is the combination of synthesis and breakdown. So if you subtract whole body synthesis, excuse me, if you subtract whole body protein breakdown from whole body protein synthesis, you get net balance. And so this is really a marker of body protein status. And so individuals who consumed the high dose during that trial had a higher whole body protein balance than during the standard dose. One interesting thing you did say, essential amino acids protective effects from muscle. And certainly we were hypothesizing that the higher essential amino acid dose would provide a protective effect. And so for those who might be familiar with this paper, we did not show statistical significance such that there was no difference between the standard and high essential amino acid dose at the muscle level. There could be a variety of reasons for this. So that standard dose, when you calculated that 0.1 grams per kg per body weight for actual gram amount, it came out to around eight grams of essential amino acids. And when we look at the rest of the body of literature, there’s a sweet spot for maximizing muscle protein synthesis around eight to 11 grams. So it could be in this study that while there was a greater benefit at the whole body protein level of the higher essential amino acid dose at the muscle level, we had likely maximized our response. And this makes sense from a ideological perspective. At the end of the day, as I mentioned, during a stress state, the muscle acts as a source of amino acids for the rest of the body. This is an evolutionary protective effect. The body knows that immune function trumps muscle growth. The body knows that protein synthesis in the gut is more important than muscle protein synthesis during a very stressful state. And so my colleagues and I certainly allude to this in our discussions in our papers that this whole body metabolic triage effect does seem to make sense. The body’s going to prioritize higher order protein synthetic processes over the muscle. The study was really well done. And for you guys listening, I’ll link it. It’s the effects of high versus standard essential amino acid intakes on whole body protein turnover and mixed muscle protein synthesis during energy deficit, a randomized crossover study.

 Well done. Have you thought about how that can translate to the population as a whole, how that actually translates to the service members? And by the way, the participants were there were 19 males, mean age of 23 years old, and they were involved in this randomized double blinded crossover study. As Jess said, this was they underwent two, so they went to five day energy deficit period separated by 14 days. They looked at muscle protein synthesis and whole body protein turnover measured at rest. And after there’s also resistance training here, which I really thought was well done. Thank you. And for those of the listeners that are unfamiliar, this was a unilateral leg model. So there’s a resting leg that remained rested for the whole day. And then we had the individual perform leg extension and leg press with one active leg. And that allows you to compare the rested to the active leg within the same day. Really, really well done. And I’m curious, has anything changed in terms of, and you may or may not be able to say this, but the offering of essential amino acids as part of a protective measure in an energy deficit or in a high training demand, this could probably be translated also over to Doug Patton Jones’s work, which he talks a lot about catabolic crises and the protection of skeletal muscle as an amino acid reservoir. Have you guys achieved any of the recommendations? If you can say so, or if you can’t, we’ll just– Sure, that’s a great question. So the first is two parts. So I’ll take the one with the perspective on constantly pursuing the evidence basis for updating our rations. And what I mean by rations, for those of you who aren’t familiar, our service members consume ration platforms. So these are packaged foods that they carry on their person into the field environment. So into the woods, up the mountains, out into the deserts. So they carry all of these rations on their person. They’re highly shelf stable. There’s a lot of food technology and very intentional design into the packaging of these items so that they can be dropped from airplanes, so they can be shelf store– shelf stable for a certain amount of time so that they’re readily available. So when you’re considering what is going into the ration, certainly the nutrition component and formulation is very important. But also for listeners that are unaware, the logistics of maintaining a viable food source as a ready to eat on the go entity is extremely important for service members.

 And so to your point, the concept of moving this laboratory study as well as the series of studies that followed it over into changing recommendations or changing those food platforms is an ongoing project. And we have a direct partner at the Natick Soldier Systems Center in their combat feeding division. And their job is really to take the science-based evidence that the US Army Research Institute of Environmental Medicine, my institute, specifically the Military Nutrition Division,

 what we establish as scientific evidence for evolving rations and improving requirements gets translated directly to them. Yeah, it’s fascinating. I actually looked at some of the rationing information during World War I and World War II. Have you ever looked at that? Have you ever looked at how high their protein intake was? I believe that they were rationed at least one pound of red meat. Do you remember that? It is honestly very fascinating of how rations evolved, how our institute evolved, how our Soldier Systems Center evolved. It’s amazing how they pursue food technology in that era is really interesting. I feel very happy that I’m not alone in finding it incredibly interesting. If you guys really wanted to nerd out with me, please message me. I will send you some of these World War II rationing pamphlets. Have you ever seen the old pamphlets? I mean, I will send them to you. They are extraordinary. Basically, they had put guidelines, recommendations of what it would look because at the end of the day, they needed strong people. They needed strong, capable soldiers, strong, capable workers. They were very heavy on, they recognized this very early on that high quality animal based proteins would support the needs of a body. It talked about minimizing process. This was in some of the rationed pamphlets I was looking at. They were, I want to believe that they were in the 40s. It was amazing to see and that they said if you really wanted to do a poor job for Uncle Sam, you would move to processed food, white flour, and a lower protein diet. You’ll have to send me that updated or that pamphlet specifically because I haven’t seen that one. It sounds really cool. I’m sure they have it across the street. They’re really neat display of all of the rations and how far they’ve come. It’s really remarkable. It is. And if any listeners out there, if you’re really looking to send me a present, I would love to get my hands on one of those older, I don’t even want to say propaganda, but it was this passed out material. I would love a copy for any of those history buffs. I will return back to our questions. These are highly, I just want to set the stage for the listener. These are highly curated questions. And we have agreed to follow a flow and a program so that I had the capacity to bring you Dr. Jess Gwynn. I am moving on to my next question. What challenges do you foresee in implementing essential amino acid density recommendations in practice, especially for individuals following a plant-based diet? Right. So the first half of that really, and again, I have a great focus on bias to my focus, but it is narrow. It is on amino acid metabolism in the protein space, but branching out to greater nutrition. The way for us to move forward with a change in macronutrient or protein intake recommendation is also coinciding with an improvement in nutrition education. And for an individual to understand how to make the best protein choices, I think we need improved nutrition education overall. And certainly I don’t want to sit here and call out a problem without a potential solution, but it will take a large team of professionals. And

 we have the opportunity in the US in many of the STEM-based college courses to take a nutrition class, but I don’t remember taking a nutrition class in high school. And I most certainly don’t remember nutrition being discussed in elementary school. So I think pairing up the physiologist, pairing up with public health experts, with nutrition education experts, with behavioral change experts is really the way that this has to go. And that’s very complex. It’s not as simple as just providing a protein recommendation. I’m really glad to hear you say that because that is one of the things that we’re really facing right now. We are an overfed nation. We can all agree. I would say perhaps not the special operations community, but I would say the military at large. Just in general, people in our community and our culture are overfed. And how can we reconstruct a nutritional plan to allow for not just adequate performance, but optimization of performance, whether it is military, whether it is that you are a mom, anybody. And what we have to fight through, from my perspective, is the information overload that we’re hearing and the oversimplification.

 It’s important to make baseline recommendations that we can agree upon, that we know they can support health like protein. That potentially modifying carbohydrate intake if someone is metabolically unhealthy, obviously managing calories, these things play a role. Yet,

 there is a simplification that has to happen, but then there is a substantial increase in education that we must gain because of all the influx of information and new foods that become important. And this really brings me to my next question, is the discussion of the metabolic differences between animal-based and plant-based protein equivalents as highlighted in your research. Absolutely. So this brings us back to the discussion of the dietary guidelines on equivalents.

 And so again, this is a concept of protein quality. So an animal-based source is going to provide a higher amount of essential amino acid content compared to your typical plant-based amount of protein. And I want to be clear that certainly you can pursue a plant-based or plant forward diet that provides an adequate amount of protein, an adequate amount of essential amino acids. In our paper, we modeled this and individuals were getting above the RDA for essential amino acids. But again, to your point, the RDA is really a starting point for baseline health.

 And to pursue something more optimal, it’s going to take a concerted effort if it’s going to be plant-based, solely plant-based. And one question perhaps I have for you as well as the concept of how do we name plant-based diets? Plants consist of, our diets consist of a large amount of plant foods to begin with. And so individuals who are plant forward could still achieve a plant-based diet while incorporating animal proteins, if that makes sense. You have a large majority of your total dietary intake coming from plants. And with that, you can still consume foods that have a high nutrient density, meaning all of those additional important vitamins and minerals are still coming along with a plant forward diet, including animal-based proteins. So to simply answer your question, the difference in animal-based proteins and plant-based proteins really comes down to their essential amino acid content and their total protein content. Again, that’s going to require more nuanced intention for an individual to consume a complete amino acid profile. They’re going to have to pair foods like the commonly referred to combination of beans and rice. So those two plant sources of protein are limited when they’re not combined. And sure, you can combine them, but then there’s still an energy component of the combination of beans and rice, whereas you could probably achieve or you can achieve the same amount of protein and the same amount of essential amino acid content with an animal sourced amount of protein. That’s well said. I want to add to that, if I may, the metabolic differences. One of the things that we see about dietary protein is that it increases the thermic effect of food. So the thermic effect of feeding, this is the amount of energy that it requires. And I’m going to say this loosely for the body to “utilize” the protein. For example, if you were to eat a hundred grams of pure protein, which we typically eat mixed meals, but a hundred, I’m sorry, a hundred calories of pure protein, the percent utilization could be 20 percent, if not even higher, which means the net energy intake that you see from that would be 80 calories. Now I bring this up because I don’t think in the literature that one, you will see there is a variation in the literature that the thermic effect of food of protein could be 15 percent, sometimes it’s as high as 25 percent. I have seen potentially if my memory serves me even higher than that, although albeit not typical. And the variation, I believe, and also my longtime mentor, Dr. Donald Lehman believes, that it is because of the skeletal muscle effect, the triggering of muscle protein synthesis being a highly dynamic and energy consuming process. If one removes the high quality protein, again, these are just laying out a hypothetical and another way of thinking about this difference between animal-based proteins and plant-based proteins, if you then begin to ingest lower quality proteins that are limiting in the essential amino acids, then you will begin to see a decrease in the thermic effect of food. And at the end of the day, one thing that we can all agree upon is that body composition matters and how do we create a nutrition plan that improves satiety while controlling for calories.

 I just want to put that at your feet, no need to comment unless you want to, but I think that that potentially is another way to think about the metabolic differences of animal versus plant-based foods above and beyond the protein quality. Yeah, absolutely. Some good thoughts.

 This is what I do in my spare time. Aside from trying to pick up dirty clothes and food on the floor, I’m thinking about the differences of amino acids. But hopefully if you’re listening to this podcast, you are also potentially doing the same. In your opinion, what are some of the most pressing research gaps or unanswered questions in the field of protein quality and essential amino acid density that warrant further investigation? I love this question because this calls me on the rug for future research questions, right? You’ve got to keep thinking forward. So definitely the consideration of how essential amino acid density or protein quality plays out in mixed meals. And so one piece of the literature that some of your listeners may or may not be aware of is that a majority of the protein work has been done primarily because of the methodologies involved on single isolated protein sources. And what I mean by that is isolated protein sources such as protein powders or a single glass of milk or a single egg or a single fillet of salmon, for example, and only recently has the field shifted to also be considering mixed or whole food meals. And what I mean by whole food mixed meals is there’s a protein component. So a, for example, a piece of steak, but then there’s also potatoes. There’s also a vegetable. And that’s really how people eat. So at the end of the day, we should be pursuing science that captures the way that individuals are eating. And I want to be very clear, this is not to discount the decades of work that have been done in the protein field because very much so that was necessary to lay our foundational understanding and knowledge. If you don’t isolate proteins at the very beginning to best understand the mechanisms of action, then we don’t have a strong understanding of how protein affects physiology. So just to be very clear, the foundational work that has been done to date with isolated proteins is really a strong storyline and is the information we need to move forward. But again, pressing research gaps really include how does a person eat across the day, over time, over months. And this leads into my next research gap is the implementation of longer term functional outcomes. And as I mentioned with isolated proteins, much of our work is also in the acute setting. And what I mean by acute is a four hour feeding response or a 24 hour response or even a 48 hour response. But again, a lot of the functional outcomes are really going to take longer term studies to assess. So looking at weeks to months and for some potential quality of life interest areas following nutrition interventions, that’s going to take years. And so I definitely think with the protein quality and EAA density space,

 certainly trying to apply these concepts, working with nutrition providers to see if they’re even practical. Certainly in the lab, we can consider potential solutions, but these have to go out to the testing space and be applied with individuals and see if they’re actually practical for them. Yeah, it’s going to be fascinating. Don Lehman and colleagues are working on an essential amino acid score. Have you heard of that? I have heard Don talk about this. And it’s an exciting new development. Absolutely. This idea of because you guys listening, what I want to do is I want to provide information for you that allows you to open your mind to the nuances of the discussion, as well as actionable takeaways. So so far, we’ve really discussed this protein whole food amounts alongside the essential amino acids. And I’m just curious, have you found or have you looked into the literature about any of the outcomes of limiting essential amino acids like methionine or lysine or leucine? Have you come across any of that in your research? And you don’t need to study for it. Just again, any knowledge that that you happen to have and would like to share with us. To be honest, beyond the standard understanding that at a certain point, all amino acids are needed by the body. I’m less familiar with limited amino acid literature, just to be honest, certainly more familiar with the importance of essential amino acids being able to rescue negative detriments. So you mentioned Dr. Doug Patton Jones’s work, and they use leucine to pursue rescuing the atrophy occurring following bedrests and hospitalization. Also, our collaborators at the University of Arkansas Medical Sciences, Dr. Frando and Dr. Robert Wolf have also used essential amino acid intakes post surgery.

 So I think I’m more familiar with the literature using essential amino acids as an additive approach to rescue these negative effects of catamolic stress status. And have you thought about dosing? Some of your earlier work, again, you did it with the eight grams of essential amino acids with your work with the military individuals. Have you thought about it beyond that for, I mean, it probably translates maybe a little bit higher again for the aging individual because of the muscle protein synthetic response or even the slower protein turnover? Right. So certainly we haven’t done that work in my laboratory or with my collaborators firsthand. But when you do look at the literature, you’re right. There does seem to be a dose increase or an increased requirement as we age for total protein intake, as well as amino acids, essential amino acids. And this could be, and you know the literature just as well as I do in the longevity space, this could be due to a reduced ability to digest and absorb protein as a whole food in the gut. This could be due to reduced muscle sensitivity or what we sometimes term as anabolic resistance. And we’re still teasing out the actual mechanism or reason why individuals become anabolic resistance as they age. And the term anabolic resistance is also more nuanced, right? So anabolic resistance in a young individual who’s going under an energy deficit is very different than anabolic resistance in an aging individual. So to your point about dosing and aging, I think the literature has really done a nice job of arriving at a consensus that protein does become increasingly important as we age and that it is to support overall lean mass, but that there are considerations for total quantity as well as the types of protein consumed. So not to get too far off on a tangent, but going back to the eating behavior perspective with protein as well, these individuals are often consuming fewer calories and unfortunately they’re also less active. And so now we’re kind of battling a reduced total amount of protein intake coupled with a lower sensitivity of the muscle because they’re not as physically active.

 So in light of all that, consuming essential amino acids in a powdered form may be an easier way for them to get those overall protein needs. I really like that you brought up gut health. It’s something that I do all the time in my clinic. We have a full clinic. Part of it is online and we address a ton of gut health. And one of the challenges is that when individuals have impaired gut integrity, whether they have “leaky gut,” I use that term loosely, or they have impaired stomach acid, which typically can happen with aging. When an individual has impaired gut integrity, it does affect their absorption, their ability to absorb these nutrients. And the amino acids are not

 out of the woods, as they say, right? This also will happen to proteins. And I’m really glad that you had brought that up. I would love to pivot a little bit if you would indulge me in some of the work with Heather Lydie. Because of the satiation factor, there’s a ton of discussion about GLP1 and Agnes. And with that discussion, there’s a lot of talk about protein and satiation.

 If you would share with us some of the data that has come out of her lab, perhaps one of which you’ve worked on, I would love to bring that to the listeners. Yes, absolutely. So for the reviewers, we do look in the laboratory at eating behaviors, focusing on hunger and fullness and satiety and food reward. And dietary protein has really emerged over the last 20 to 30 years as a primary driver of satiety. In that way, protein increases fullness and reduces hunger. And so we can leverage, and this is primarily work from my advisor, Dr. Heather Lydie, we can leverage dietary protein intake to increase an individual’s feelings of fullness and to increase satiety. And what this does is this helps lay a foundation for reducing overall intake or overeating. And so for one example, increasing dietary protein intake in the diet increases fullness. And it can also lead to reductions in intakes of high carb, high fat foods. So it’s two-pronged approach. You’re reducing overall intake because your feelings of fullness are higher and your feelings of hunger are lower. But then also this food choice piece comes into play. When we’re extremely hungry, maybe even hangry, it’s easy to reach out for those high food reward foods, right? So foods that are highly palatable. And what I mean by that, high salt, high sugar, really, really rewarding to consume. And I know many of us can totally relate to that, how a bag of potato chips when you’re really hungry just hits the spot. And so, yeah, in her laboratory, she’s been very interested in using dietary protein, particularly at the breakfast meal, because it’s an easy target. It’s typical of US adults and children as well to consume less protein at the breakfast meal than at the lunch and the dinner meal. And so she’s targeted breakfast to include higher protein breakfast. So this is on the order of 20 to 40 grams, depending on how you define higher.

 But really just can we move some of the protein back to a breakfast meal and how does that impact hunger and fullness? And overall, we generally see that it increases appetite control. I wanted to point out to the listener, you said between 20 and 40 and it was done with high quality proteins. One of her papers looked at it was roughly, I think it was 38 grams of protein for breakfast. And the reason I’m pointing this out, because the dose that we would think to stimulate skeletal muscle also is the same dose that it appears to have an improvement in satiation and gut peptides. For individuals listening and thinking about how they would design their diet, that the conversation is not solely just about muscle, but really how do we leverage protein that number one, yes, can target muscle, but number two, in an appropriate dose also has influence on hunger and satiety. And then of course, this thrombic effect of food. And that’s where I think that the dosing comes into play, because again, we can all agree that it’s a 24 hour period that matters, but there are certain things and strategies that an individual can use if you struggle with an overzealous appetite, if you struggle with constantly craving carbohydrates, if you are in a highly catabolic state or sedentary, there are strategies, while subtle, can be very impactful. Was there anything that surprised you that you found unexpected during your research on essential amino acids or protein as a whole? All right, so I’m gonna pivot back to the appetite perspective. And it is one of the major hurdles I think we see with free-form essential amino acids and it’s their taste. So this is just one surprising piece of how a higher dose of essential amino acids are very stringent, very bitter. And so considering the food technology piece of taking these higher doses of essential amino acids next to the next level out of the laboratory into the practical application space,

 and it was that just the overall taste of essential amino acids and how some people seem to not really mind how they taste and they see- They are brutal. They’re brutal. …the means to the end and can consume them. But then the other side of it, and our partners, we talk a lot, how do we get this to taste good? Because certainly we can do all the science we want in the lab, and in particular for our service members, if it goes out into that ration platform and it doesn’t taste good, they’re not carrying it. They’re not interested in eating it. So that part I think was the most surprising of getting into this space as a young scientist and seeing, “Wow, does essential amino acids really do have a strong taste?”

 Yeah, they’re pretty bad. Looking ahead, what are your hopes, your aspirations for the future of nutrition science and again, these dietary guidelines that we all seem to keep coming back to, especially concerning the role of protein in supporting overall health and well-being? Absolutely. I think I’ll bring us back to the concept of it is a well-intentioned framework, right? So our policy makers, our nutrition professionals and health professionals certainly are trying to achieve health and wellness for their patients, for their clients. So for the future, I think how can we continue to translate the science and do the science that needs to be done in order to make changes, right? So coming together, and this is just my opinion

 on the younger side of my research career, of how do I achieve the best rigor of science and of course pursue exploration and discovery, but then also keep in mind what’s practical for someone to use and how does the work that I do, how can it be best positioned to be used by a policy maker? Is it conclusive enough for population-based recommendation? I think that’s the other thing is, certainly we want to make changes to the dietary guidelines for America, but they are population-based recommendations. And what does that mean, population-based recommendations? I would love for you to share that piece of information because that is also a clarifying concept. Absolutely. So from my interpretation, and certainly chime in with your thoughts on this, but population-based is truly that. It is to meet requirements. They do make requirements for age, but largely it’s the individual kind of in some ways left out of the equation. It’s a very encompassing, total population-based recommendation. It’s an important point because we look at it as if it was designed, it’s difficult because to say it’s designed for an individual, it really is a guideline, which is essentially a suggestion, but it is a guideline put into place so that we meet our minimum recommendations. And it is designed at a population

 level. It is not purely just science. There is policy that comes in because we have to do our best to make responsible recommendations that end up being not just for us, but there is a global influence. And it’s understanding that and then adding to it. So I… Right. And maybe I’ll pose this question. Maybe it’s not a total revision of the dietary guidelines. Maybe those continue to evolve as our population needs evolve, but then maybe there’s more emphasis again on nutrition education and spaces where the individual touch points occur. So more nutrition education for medical providers, more nutrition education for individuals who are caretakers. And of course, that’s asking a lot. But it can be done. It is asking a lot, but it can be done. And it’s our responsibility. It’s something that 100% of people do is that they eat. And I want to highlight something else. As you’re speaking, these things are not controversial. Would you agree with that? This is not a controversial topic. It really comes down to numbers. High quality proteins, essential amino acid dosing. I think that there’s a lot of sensationalization that happens and it really distracts. It doesn’t distract the scientists because you guys are in there doing your work, but it becomes exceedingly confusing to the rest of the population. And for the listener, you guys have to understand this is not a highly emotional or charged topic. It really is based on biological numbers. So thank you for just exhibiting that. I would love for you to mention… We talked all about nutrition, but I would love for you to mention the consortium in which you’re at because they don’t just do nutrition. Absolutely. So the US Army Research Institute of Environmental Medicine is really focused on conducting biomedical research that helps support and sustain service member wellness as well as performance.

 So I’ll just highlight the three divisions. We have the military nutrition division. And as you can understand, they… We exist to provide and understand the unique nutritional requirements for service members from a nutrition perspective. So we’re responsible for providing the evidence basis to develop and improve and evolve ration platforms over time. So that information gets transitioned to our combat feeding division over at the Natick Soldier Systems Center. And really that helps continue support their exceptional work in the food technology and food science realm. The other entity that the nutrition division is responsible for is providing the oversight and guidance of Army regulations, specifically Army Regulation 40-25, as well as the military dietary reference intakes. And for the listeners, those are the overarching guidelines that indicate requirements for what a soldier should be provided, especially during those ration platform feeding scenarios, as well as in the cafeteria style or in Army terms, the defect style nutrition and dining halls. And so those are our two primary

 regulatory outputs. And then we also look towards how do we enhance performance and support a service member to be more optimal. And by way of changing recommendations, of course, that’s one avenue. But also, again, pursuing optimized food technologies and food formulations.

 I mentioned there’s three divisions at the US Army Research Institute of Environmental Medicine, so I don’t want to leave the other two out. There’s the Military Performance Division. They are highly focused on preventing musculoskeletal injury. So they are pursuing research focus on maintaining bone health, reducing stress fractures, also optimizing psychological

 performance. And really, even things as simple as biomechanics, how do we pursue the best type of biomechanics when a soldier is training? And so the performance division really is a great umbrella of all of performance-based work that a service member might face. And then additionally, we have the Thermal Mountain Medicine Division. And so they, as it implies, focus on work that is done at high altitude. They’re also interested in heat, as well as cold. How do we keep a service member operating their best in all of those extreme arduous environments? And so their research really focuses on overcoming those unique thermal and mountain challenges. I think that that is extraordinary. You guys are extraordinary. The work that you’re doing is making a difference in a contribution. Dr. Jess Gwynn, thank you so much for your time. I know how busy you are. It is truly an honor and a privilege to be able to have conversation with you. Absolutely. Thank you, Dr. Leon. It’s a pleasure of mine, as well, to share all of the great work that my team has really invested in. So thank you.