Body Composition and Muscle Loss on GLP-1s with Dr. Nina Crowley. RD

If the scale is going down, how do you know what you're really losing? In this episode, Ana Reisdorf sits down with Dr. Nina Crowley to break down what body composition actually means, why BMI misses so much of the story, how DEXA and bioelectrical impedance differ, and what GLP-1 users should understand about fat loss, fat-free mass, and the ongoing conversation around “muscle loss” during weight loss.

Guest Bio:
Dr. Nina Crowley, PhD, RDN is an expert in obesity care, body composition, and behavior change. With a background as a bariatric dietitian and a PhD in health psychology, she helps translate complex science into practical, real-life strategies. As Director of Clinical Thought Leadership & Partnerships at Seca, her work focuses on helping people look beyond the scale, understanding changes in fat, muscle, and metabolic health, especially in the era of GLP-1 therapies. Nina is also the host of In the Know with Nina, where she breaks down topics like GLP-1 medications, muscle preservation, and sustainable behavior change in a way that’s clear, compassionate, and actionable.

Guest Links:
LinkedIn: https://www.linkedin.com/in/ninacrowley/
Podcast Channel: In the Know with Nina Podcast

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*The content of this show is for informational purposes only and does not constitute medical advice. The goal of this show is to provide various points of view about GLP-1 Medications. The personal and professional opinion of the guests and their content does not necessarily reflect the opinion of Ana Reisdorf or GLP-1 Hub.

Transcript

SPEAKER_02 0:00

That's kind of where we're at, especially in the GLP one space of people talking about muscle, right? There's a lot of talk about muscle. There's also a lot of misinformation out there about what really that assessment is in the research studies of how much muscle someone might lose with taking medication. And that's where I get to really nerd out and say, like, oh, are they really using the right assessment tools? Are we really representing that right? So, you know, we'll see these studies that say 25 to 40% loss. And if they're saying muscle, I'm going back to that study and saying, What are they really assessing?

SPEAKER_00 0:34

If the scale is going down, how do you know what you're really losing? Welcome to the GLP1 Hub Podcast. I'm Anna Reisdorf, registered dietitian, GLP1 user. Today I'm joined by Nina Crowley, a PhD and RD, to talk all about why BMI misses so much, how body composition testing gives you a clearer picture, and what people on GLP1s should know about muscle loss and how often to measure their progress. If this episode helps you, please leave a quick review on Apple Podcasts or Spotify. And if you're watching on YouTube, make sure you share your thoughts in the comments. Now let's get on to the episode. If you're on a GLP 1, something no one tells you at the beginning is that eating enough can become the hardest part. At first, the weight comes off fast. It feels great, but what's happening underneath is not always as straightforward. Your appetite drops so much that you're not just eating less, you're often missing key nutrients, especially protein. And that's when things like low energy, muscle loss, or even hair changes can start to show up. You might try to fix this in the obvious ways of just eat more protein, focus on whole foods, but honestly, sometimes you can barely get in more than a few bites. That's where MAVA comes in. It's designed specifically for people on a GLP1, so it actually works with your reduced appetite instead of against it. It gives you high quality protein, collagen, fiber, plus essential vitamins and nutrients all in one. So even if you're not eating much, you're still covering your bases. It's not a quick fix, it just makes everything feel a lot more manageable. If you're on a GLP1 and not thinking about your overall nutrition yet, I would start now. Head to MAVA.co and use the code ANA20 to try MAVA for yourself with 20% off your first order. That's MAVA-M-A-E-V-A Co and use the code Anna. Welcome to the GLP1 Hub Podcast. I want to welcome one of my lovely colleagues, Dr. Nina Crowley. She does all the things with obesity advocacy, talking about body composition. So I will let her introduce herself because I'm certain certainly she will do a better job. Thank you for coming on the podcast. I'm so excited that you're here.

SPEAKER_02 2:49

Thanks so much for having me. Yeah, I love to talk about all the things. So my my short background, I'm a dietitian by training, you know, worked in a bariatric center, was my very first, you know, place where I found my home and immediately went to school to get my PhD in health psychology to be a better dietitian working in that space. So that's really where a lot of my background comes from. I was there for 10 years. And then when I got my PhD, I decided I wanted to be more in leadership and do all the things that I couldn't do for my role. So I did that for six years. So I was at MUSC in Charleston for um 16 years with the bariatric program. And then um, and then I came to work for Sika, which is a company that makes body composition equipment. And I've been with Sika for the past four years. So I'm the director of clinical thought leadership and partnerships, which means I get to be talking about all the things I love all day and going to the conferences where we get to interact with our colleagues and learn more and talk about all of this. So that's that's been a really nice move for me. So yeah, so I've been, you know, I just got introduced somewhere the other day as being in the field for two decades, which sounded crazy, but I guess that's true. 20 years in obesity care. And um, it's it's been a really fun time the past several years where things have been moving a lot quicker in the bariatric space for a long time. I would not have had daily things to post about uh on social media because no one was listening, you know, even though surgery was an effective treatment and you know, for for the people who had it, it was great. It was just not as widely known, widely used. And so it's been a great time sort of talking more in the GLP1 space and especially with body composition. It kind of was a right time, right place kind of thing for me. So I'm happy to be here and talk about that with you.

SPEAKER_00 4:38

I we actually started a similarly. I also started in bariatrics. And the reason why I left bariatrics is because I felt like I didn't understand that emotional component. And I was like, Okay, oh, I didn't know that part. Yeah, you went to get a PhD in it, and I was like, I'm just gonna quit.

SPEAKER_02 4:53

Well, I didn't say it was the most financially sound or smart thing to do, but it definitely gave me a better perspective about behavior change and you know, really understanding people with obesity. That it was not, you know, I think probably naively. I I thought you could go learn all the things and teach and tell and and have people do all the things that you knew, and it would just be that simple. So that sort of that foundation of human behavior and how we change was really helpful for even for being, you know, in counseling practice as a dietitian. I'm not a um licensed therapist, but but having that background, you know, I always say made me a much better dietitian. And so now I'm using, you know, those skills in different ways and actually being able to talk a lot about um, you know, ways to talk about our outcomes other than just weight. There's such a psychological component there. So I do feel like I get to kind of use all the all the parts.

SPEAKER_00 5:50

Yeah, yeah. I felt like that was what I was woefully unprepared for, was that I also thought I I'm passionate about helping them. Why would I not be able to do that? And then so many things came at me that I was not ready for at all. And I, yeah.

SPEAKER_02 6:04

But that's also probably what makes you so good in this space now, too, is that you know, the obesity space is not new. And counseling people who have, you know, excess weight is not a new area. And we really did have a focus on interdisciplinary care in bariatric surgery, even 20 years ago when we started in our careers. And so I think that I'm often saying, you know, it's it's cute how everybody thinks this is new and they're coming at it with a brand new angle. I'm like, oh, we've we've learned so much. So I do, I do feel a little, you know, kind of professional responsibility to be able to share what we've learned so people don't make the same mistakes or, you know, get started, you know, from what we've learned and not just going back to square one with, you know, let's just tell people what to eat. Let's just educate them. Let's, you know, it's just about the food or it's just about, you know, whatever. I think we're finally starting to see people understand that it's, you know, it's biology and it's all these other things to get an optimal outcome.

SPEAKER_00 7:02

Yeah, I hope so, because it's much more complicated than people would like for it to be. You know, I just sent an email about that to my newsletter, like it's really not black and white. You gotta consider a lot of different aspects of this.

SPEAKER_02 7:14

So it's it is funny too in the in the social media space too, because it's you've gotta make it you've gotta make it simple, but understanding that it's not easy is really it's sort of riding between that that space. So if you oversimplify it, it doesn't do it justice. And people are like, well, if it were that easy, why can't I do it? You know, but you've got to make it simple enough that it doesn't seem like a super high barrier to be able to be able to make some change in any area.

SPEAKER_00 7:44

Right, right. All right. So let's talk about body composition. What does that mean? Why do we change and and like how should we think about that?

SPEAKER_02 7:52

Yeah, all right. Well, real, real high level um, you know, body composition is looking at the different compartments of our body and what they're made up of. And so there's a lot of different assessment ways to do that, but we're we're really trying to get at, you know, in a very simple way, you know, how much of your body is made up of fat or or fat molecules, that's one way to look at it, or the tissue level way of how much is adipose tissue. So you can kind of look at it. There's five different levels that's very high level. We won't go there, but just to know where there's a a bunch of different ways to assess that. When we were in school and learning as young dietitians, we learned about all the different ways from things like underwater weighing to MRI to you know, all these different ways that seemed really research-based and not accessible to the patient. We've come a long way in the research area for body composition to say, like, we have these ways to assess how, you know, what your body's made up of. And then there's newer technology that's validated to those older um, you know, research ways to sort of do an all-day assessment of the four compartments of your body, for example. We would never do that in a clinic, or we would never have a patient go do that. But the methods that we have nowadays, and in particular, we can talk about bioimpedance, which is which is what I spend most of my time talking about, those are things that have been validated to those in-depth research methods or imaging techniques like MRI for muscle mass, like DEXA for fat mass. And so we're able to then say, this is like 97 or 98% in agreement with those reference methods, we feel confident that we're doing a good job estimating your body composition to be able to give you that feedback. So from a from a real big picture way, it's that assessment. Once we get into the different methods of how to do that, you know, there's there's a lot of nuances here, there's a lot of pros and cons to each approach. And I always think, you know, and you may share this feeling from back when you started, was there were these very abstract ways to assess body composition. And then you would get into a practice. So, you know, for me, it was getting into a bariatric clinic. And you either had or didn't have body composition assessment. We didn't have it. So we just had, you know, weight and BMI. And so you know, going through talking to patients about their, you know, their weight was very simple from that, you know, we just have this metric. There was a lot of, a lot of emotions and feelings and all of that wrapped up in that metric. But that was what insurance companies used and still do to, for the most part, to assess how someone's doing. I didn't feel empowered back then to be able to say, there's something better out there. We should be pursuing this. Like this is my ask. Every year, I, you know, I want to get something new, and this is what my ask is. Now I feel like even dietitians and other clinicians are able to say, okay, we're hearing clinically weight is not enough. We're saying it to patients behaviorally, um, you know, biologically, but you've got to sort of then make that jump to say, let's well then let's find out how we're gonna show someone that it's different. And so luckily, in those, you know, 20 years, we've been able to see the technology improve a lot. So bioimpedance, which if you want, we can kind of dive into that a little bit. That is a way that we do it in a very fast and easy way in a clinic. And it's got really nice data when it compares to those reference methods for tissue assessment.

SPEAKER_00 11:16

So let's start with the difference. You mentioned BMI. What's the difference between body composition and BMI? I think there's some confusion.

SPEAKER_02 11:24

Okay, good. Well, that's yeah, that's a good one. So one of the ways you can assess your body composition is by just the total mass of your body, right? It's not really the composition, it's just weight of your person, you know, against gravity, right? So, so just your weight or your mass is a number that is part of the picture, right? And so the weight, you know, using BMI has been on, there's a long and interesting history of where that came about, but really it's looking at your height divided or your weight divided by your height squared so that you're able to compare across heights doesn't necessarily take into account gender differences, ethnicity differences. And so that is where some of the more complex measures of body composition are able to tell us. Here's maybe where you should be given these demographic variables that you have. So BMI is just very simple weight over height squared, and it's something that you can calculate, you can put it into the, you know, search and ask, you know, the internet to tell you what your weight is. And then there has been classifications for BMI for for several, you know, decades now of where you stand for a classification on obesity. And so um, even though there's been a lot more talk lately, this was something I just got back from a conference where we're debating, you know, there's different systems and classifications and staging for obesity. Um, in general, we still, for the most part, publicly talk about, you know, hey, is your BMI 30 and above that kind of classifies you as obesity, as having obesity. That's just so simple and people continue to use it because it requires zero effort, right? The thing is now we do have better methods. So body composition will say, you know, it will be able to give you a report, you know, depending on the method, a report of some sort that has different parameters. So you would look at maybe your fat mass and your fat-free mass. Those two numbers are the different components of your body. The fat mass is all the fat molecules. Fat-free mass would be all the molecules that are not fat. That's two compartments. There's another, you know, you can drill down further and look at if you did a DEXA scan and you looked at your fat and your bone density, the third component would be your lean, soft tissue. Everything that's soft, not bone, and lean, not fat. So those three components, fat, bone density, and soft tissue is what you would get from a DEXA scan. And then we can drill down even further than that and look at your um your skeletal muscle. And so that one takes a little bit more work to get a really good number because the skeletal muscle is not like a molecule of muscle, it's a tissue. So tissue level assessment. We want to look at something like MRI, which is the gold standard per se for assessing skeletal muscle right now. Um, you would look at that and be able to tell someone what's your skeletal muscle. And then that's kind of where we're at, especially in the GLP1 space of people talking about muscle, right? There's a lot of talk about muscle. There's also a lot of misinformation out there about what really that assessment is. And then maybe we can talk about this too in the research studies of how much muscle someone might lose with taking medication. And that's where I get to really nerd out and say, like, oh, are they really using the right assessment tools? Are we really representing that right? So, you know, we'll see these studies that say 25 to 40% loss. And if they're saying muscle, I'm going back to that study and saying, what are they really assessing? And that number in particular, they're really looking at the fat-free mass, which is almost double the amount of skeletal muscle if you really kind of get down to the nuts and bolts of it. So that's really the big difference between a weight-only assessment and body composition. And I think, you know, BMI has gotten a lot of a lot of press, a lot of bad press. And most of us are like, hey, it's much more than weight on the scale. I don't, I don't know that that number is going away completely. So I don't know if it's an all or nothing like never use weight or BMI, but it really is much more in the screening and population level assessment than it is helpful for the individual. Though, you know, we both know in working with patients over the years, people see a number, they hear a number, they get really focused on that being the goal. Or people have told them, hey, your goal is this, or hey, you don't get treatment unless it is this. And so there is just so much wrapped up in those numbers that's really hard to it's hard to pull people away from that, even when we have good data in all these other compartments.

SPEAKER_00 15:49

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SPEAKER_02 17:33

That's a perfect question. So with so in particular for something like MRI, those would really be considered sort of the reference standard. So, like when new technology is being developed, you want to look at how well your technology estimates muscle mass. If you did it on the same day in the same conditions as an MRI. And if you did both of those together and you're looking at sort of a graph, you want that to be as straight of a, you know, line correlation as possible. Like, you know, your MRI says your muscle mass is 50 pounds and your bioimpedance says your muscle mass is 50 pounds. As close as those two things can be together, we would like to see that so that then we can feel confident that the bioimpedance scale in the office that you're able to access much more easily is accurately estimating the thing we want it to estimate. So there is, it's it's a really good point because the the confusion around gold standard best, you know, metric to use often means like we don't need to get that close. We don't need to see the imaging itself on an MRI for someone to assess their body composition. We just need to be sure that the ways that we understand the ways those are being done, because I also suspect that having confusing numbers is also problematic, just like having, you know, being too focused overly on certain metrics. Um, if people are assessing a a lot of times there's home body scales or home, you know, smart scales that people get that they make some big and wild claims sometimes about how good they are at estimating body composition. And, you know, I'm not here to necessarily poke holes in that, but if you're doing that at home every day and your numbers are fluctuating a good bit, um, that can be problematic, I've seen, because people are like, well, what do I do? Is this right? Am I eating this particular thing and then seeing this result? Is it is it that tight to, you know, be able to assess that? And so I would say, you know, in that category, if you do have a at-home smart scale that's giving you a measure of body composition, it's worthwhile to dig into that a little bit, or if you're working with a dietitian or a clinician to be able to, you know, talk with them about how good that device is at estimating your body composition, but also that you're not doing it too frequently. Because I mean, the reality is is your actual body composition is not changing day to day. There's noise and fluctuation just like there is with weight. If you're working on, you know, a treatment plan that includes medication, you would want to assess that probably every one to three months at the most frequent, right? So we don't have a there's not a guideline out there that says exactly this is, you know, how often to do it. But from what I've seen, you know, one to three months is probably common practice without overly focusing and getting too hung up in small changes. Because again, every every way to estimate your body composition has a little noise and error in there as well. And so we just want to make sure that it's helpful information. And again, that's you know, back to the psychology part of this. We don't want just another set of 20 different new numbers that are, you know, not helping someone move towards the behavior change that they're working hard to do. Or, you know, you're taking it an agent to change your biology that's working really well. We don't want to, you know, get hung up in like it's not enough. It's, you know, in in some of those conversations by overly focusing on maybe the body fat percentage is still over what you thought it should be, or you know, you've been working really hard to increase your muscle mass, but it takes a long time to build muscle mass. And so is it not responding fast enough? Like these are some of the things that I think make the clinician still a big part of the conversation, that it can't just be a tool or AI giving you that feedback. I think we really, we really need to still have folks like us who can help, you know, temper that number and help put that into perspective and use it to actually help you move forward and not just confuse you or make you spin out of control.

SPEAKER_00 21:31

So would your recommendation be maybe to like pick a method that's accessible to you and then use it like consistently, like let's say a bioelectrical impedance at your doctor's office, and then just like go with that one every three months, six months, however often you can do it? Would that kind of be a good about it?

SPEAKER_02 21:49

Yeah. And you know, there's even again, I don't we don't have to get too deep in the nuance, or we can, but even something like a DEXA, you know, they've been a little bit more available. So looking at, you know, remembering that DEXA's going to give You those three numbers: the fat, the bone, and the lean, soft tissue. To me, lean, soft tissue is not a word that people really get or understand. They're like, and when you look at a DEXA readout, sometimes they'll tell you lean mass, sometimes you'll hear the word lean body mass. This has now become one of my big, you know, sort of soapboxes is to teach clinicians the right language to be using. So if it's telling you that number, that's not necessarily your muscle. They'll apply a calculation to figure out how to take that lean soft tissue and estimate your muscle. But DEX is one of those technologies that you really especially want to be on the same device, even in a place that has four different devices in a, you know, in a clinic or in a center, the same one in the same room, like they've said, you know, to reduce the error there. So you definitely want to do that. And there's how I mentioned about the molecules versus the tissue level assessment, they're not all interchangeable. So if you're looking at body fat estimated from one to the other, there's going to be a little bit of of noise and movement. And even among, you know, different brands of a particular technology between, you know, bioimpedance, you might see some differences in numbers. So again, it's like taking that and saying, how can I use this data to help move me forward on the things that I need to work on and not not get too hung up in some of the emails that I get all day are people who are, you know, there's 0.5 change in this and that, and we've been doing, you know, like they get too close to it. And it's sometimes hard to peel back and say, like, why do we, why are we using this? We're using this to help you, you know, make sure that you're making changes that are feeling like they're moving you towards your goals, to get stronger, to get, you know, more muscle mass as as you age, to lose the adipose tissue without maybe losing muscle tissue along the way, even though there may be some, you know, version of both in the rapid weight loss phase too. So I'm always trying to bring us back to we love data, we love numbers, we love trackers, we love self-monitoring, but let's make sure that we're using that in a way that helps um, helps us feel good about the changes we're making. And again, that's why I love what GLP1s have done is they've really taken a lot of the let's make this hard and let's struggle and let's suffer and whatever, to say, like, let me enjoy my weight health journey and make sure I'm focusing on the right things. So, you know, you'll you'll assess somebody at the beginning of their journey to say, maybe how much should we focus on that? If you're someone who has a really high level of fat, a really high level of fat-free mass, and that's what's making up your, you know, body mass, you might have the ability to lose some of both and not feel, I mean, and that not be concerning to your healthcare team, right? But if you're someone whose weight is made up of a lot of fat, but a low amount of fat-free mass and a low amount of skeletal muscle, we might need to watch that person a little more carefully as they're losing weight to make sure that the weight that they're losing is not coming too much from that compartment. And so I do love the ability to be able to help target someone's treatment a little bit closer based on that information. So yeah, I would say what you're a long way to say what you have access to, measuring that more regularly is a good idea and making sure that, you know, at all ranges of sizes, you're able to assess that. So I, you know, we've had some patients in the TikTok community that I've, you know, become friends with. I think you know Mike and Zach. And I got connected with them because uh one of Mike's things he was saying is he wasn't able to get on a deck set until he got down to like 350 pounds. And so some of them have weight limits that would exclude many of our patients as they're getting started on that journey. So they're not able to say, like, you know, if you're rapidly losing weight, where's that coming from? Or if um, you know, you see a significant change, what are what are we really looking at here? So I think that's a piece of it too, is saying, let's make sure we can assess as many of our patients as possible before they get started. And then of course he just like wished he had that data, you know, to say, well, where am I at? Here's where I'm at now, where was I before? And then there's little things like the, you know, weight limits and the size and the capacity. And I didn't realize that in the DEXA scan, he had told me um they had to bind his arms so that he could fit in the box to be able to do that assessment. And so, you know, little things like that, as you know, make or break a patient experience. And and so that's something we want to think about too.

SPEAKER_00 26:23

Yeah. So compared to DEXA, what's the difference between that and the bioelectrical impedance? Can you because I feel like DEXA's like a scan?

SPEAKER_02 26:30

Yeah, so DEXA, you're you're it's like an x-ray, you're laying down on a, you know, on a on a bed basically, and it's passing over you from anywhere, I think, between like 10 or 15 minutes, usually you're you're laying still and it's imaging the fat, the bone, and the lean, soft tissue and giving you those outputs. Bioelectric impedance looks like a scale. So if you look at it next to a scale, you might not know the difference. What you're stepping on a plate that has little electrodes in the foot, usually two per foot. And then if it's whole body bioimpedance, it would have a hand output too. So it sends an electrical current in through your feet, out through your hands, and the speed of which that current goes through goes faster through things with water like muscle and our fat free mass and slower through our adipose tissue. And so the speed of the current is sort of the raw measurement, and then that gets put into these equations that can be used to estimate those body compartments. So that's the that's the big difference. It usually is, you know, under about a minute. You need to have no shoes, no socks. You make that connection with your hands and your feet, and then they vary from company to company. Sika, who I work with, our devices have 800-pound weight limits. They have a low, a low foot plate for a step up. So you want it not to be wobbly. The handrails fixed, so it's always in that same position. If the hands are in different positions, sometimes you can get different readings. So that's important. And then, you know, just physic physical-wise, you want it to be able to fit, you know, the the widest range of patients that you're seeing. So there's some that are, you know, much more small and simple. You know, I always say it's like a postage stamp size scale plate that you're stepping on. You want your legs to be spread apart so that it's not, so it's measuring the conductance of that current from leg to leg. So if your legs are together, it won't do that. So, you know, the the wider the bottom plate, the better. And yeah, I think, I mean, that's kind of that's kind of the big, the big differences. So it's definitely it's been a really big advancement. Again, when I learned about BIA 20 years ago, you had to lay down, you had to, you know, get your body at rest for 10 minutes and let all the water sort of settle out. It was electrodes that you clipped on. Nothing we would people wouldn't tolerate that in a clinical practice today. But they've been, you know, able to get better results from that. So, you know, it's now it's just something that I'd say to most practices, they can replace their actual scale with this because of course it does still measure your weight. So you don't have to have if you're in the market for a new scale, you might want to upgrade to a BIA scale because you're able to, you know, get a lot more rich data. And then some of them have a way to estimate your height with um or measure your height with ultrasonic height technology, which is kind of cool because I remember never having accurate heights on my patients back in the days.

SPEAKER_00 29:21

Yeah, definitely. So one of the biggest things I hear about GLP1 use is muscle loss. And there seems to be like that's kind of the main criticism that I hear from certain pre providers or practitioners. Somebody who works in body composition, like how concerned are you about that? And and what is some advice you have to help us keep some of our lean muscle?

SPEAKER_02 29:41

Yeah. Well, so look, the see your language, right? Lean muscle is not really the right term. So goodness. So to keep your to keep your lean soft tissue, but even more specifically, you want to keep that skeletal muscle, right? So what I have really dug into the literature about is looking at, you know, some of these bigger clinical trials when they're looking at uh, you know, hundreds or thousands of patients, they will do an assessment on body composition on a subset. So maybe 150 patients or something. They'll look at their body composition so that we can start to say, like, how are what is happening with their muscle over time, usually, you know, a year or more after starting and getting up to dosage on medication. So a lot of times we're able to look at their fat mass and their fat-free mass. And in general, what we've seen is you're they're losing about so of the weight you've lost, let's just say 100 pounds for an easy number, right? If you've lost 100 pounds on medication, generally about 25% of that is coming from the fat-free mass, and about 75% is coming from the fat mass. So you're losing about two, or sorry, three quarters of the weight from the fat that we want to get rid of, right? People would say, oh, you know, we want it to be 100%. But in general, you know, the even though that feels like common sense, you know, at a heavier weight, you know, some of that muscle or that fat-free mass might not be healthy tissue. And so there is some sort of, you know, thought that it's it's okay to lose some of that. Like I said, if you're if your weight's made up of a high amount of fat and a high amount of fat-free mass, it's natural that you would lose some of that. And so even looking at really well-controlled, you know, diet and lifestyle interventions and surgery interventions, that's sort of 2575, they call it the quarter fat-free mass rule. Um, and that term has kind of stuck, that kind of applies across the board. So even like the trusepatide surmount trial, looking at trusepatite versus placebo, even in the placebo patients lost a much smaller degree of weight loss. Say they lost, I don't know, I'm saying 10 pounds instead of 100, right? Those are fake numbers. But the percentage of what they lost actually was pretty similar in 2575 kind of stuck. So that's one way to look at it is that you're, you know, we're villainizing, we see that a lot, or fear-mongering around muscle loss because these are just popular and in the media and people are having that experience that they're wanting to talk about. But if we were to dive into the surgery or the non-surgery literature from before, we'd see a very similar situation. If you're losing significant weight, it's coming from both. So there's that. So there's kind of that we want to make sure that people aren't, you know, overly freaking out if they've lost some or that they're seeing a decline. There's also, you know, the difference between an absolute weight loss of one of those components and a relative in percentage. So a lot of times I'm looking at these studies and I have to sort of pull out the numbers to say, okay, this person lost, you know, 100 pounds, but they their weight, the denominator in that math equation at the end of this, also got smaller. So if you're taking, you know, I I don't have these numbers in front of me, but like if you've got 50 pounds of muscle when you started, but your total weight was 300, and then you lost 100 pounds and you now have 40 pounds of muscle, but you weigh only 200, like that's sort of what the math proportion proportionally, right? So you can even see a loss of some muscle mass, even, you know, assessed prop muscle mass, loss of tissue, but the percentage or the ratio of your body size after you've lost some weight, it might appear that it it went up, or you know, because that's just saying it it's divided by that total weight. So there's a little bit of math, you know, it's not for the for the person on meds or thinking about this, I would not get lost in the weeds there, but just to say that, you know, there is some, there's some work that we need to do in translating what happens in these research studies to the patient, because then if we're not helping them do that, they're hearing from, you know, the media that, you know, it's of a huge concern, or they'll show a picture of someone who looks vastly different and that looks like they've lost muscle, and then that can make people worry. And you know, that maybe a whole nother story about why we're overly concerned for people who are generally getting healthier, and there's a very different phase of when someone's losing weight and from when they're maintaining. And so while the goal initially might be really getting that, you know, adipose tissue down, once someone is maybe more weight stable in a maintenance phase, maybe that is when we get to focus a little more on how do we put back on some muscle tissue and and that might be a different component. So I think there's a lot of there's a lot of nuance that doesn't make it too mainstream. And, you know, again, thankful for people like you getting into the the details of that and and helping people figure out how to translate that, you know, research into their actual daily behavior.

SPEAKER_00 34:49

You know, I I think that I'd hope that everybody would work with a provider who can kind of like look at the bigger picture, you know, instead of these like black and white rules that we like to see on the internet or whatever it is. Anyway, where can people connect with you, Nina, and and learn more about your wonderful work with all of this obesity research and body composition?

SPEAKER_02 35:08

Thanks. Yeah. So, you know, for healthcare professionals, um, LinkedIn has become my my favorite way to long form be able to say what I need to say with as much nuance as possible. And so that's just my name, Nina Crowley. And for, you know, patients and clinicians as well, I do have a podcast. It's called In the Know with Nina. So that's on all the channels. And I like to interview, you know, healthcare providers who are in this space to sort of just chit-chat about what's new and what's going on and touch on body composition as well. And then I'm a big fan of Instagram for kind of that space in between, personal and professional. And I'm part of the Obesity Action Coalition. I'm on the board of directors. So from a patient perspective, they're an organization that's been around 20 years that has been doing a lot of education, support, and advocacy in this space. So that's a place to kind of connect as well. They do have in-person and and regional meetings, and they do a lot um in the um in the social space as well. Um yeah, and if you're dietitian, you can come see us all at um at Fenty this year where we'll get to kind of present together and hang out on the on the big stage together.

SPEAKER_00 36:15

Big stage. I know it's uh such an honor, and I I love that we get to work together on that. So thank you so much, Nina, for being here and sharing all of this wonderful knowledge that we still need to talk so much about.

SPEAKER_02 36:26

Yes, happy, happy to do it and and can't wait to connect in person and and get into it even deeper. Thank you.

SPEAKER_00 36:32

Awesome, thank you. Thank you so much for listening to this week's episode of the GLP1 Hub Podcast. Body composition is such an important part of the GLP1 journey. And I'm so grateful to Nina for coming on and sharing all of her wonderful expertise. If you want more support along your journey, I have a free newsletter called the Steady State newsletter that I send out every Tuesday where I give advice for your weight loss journey, but also managing all of the other emotional things that come up along the way. You can get uh the link to join in the show notes below. I'll see you in the next episode.