Episode 260: Muscle Matters: Are You Losing Muscle While Losing Weight?

[00:00:00] Welcome back to the Back on Track: Achieving Healthy Weight Loss, where I help you get on track and stay on track with your weight loss journey. I'm your host, Dr. Alicia Shelly. So let's get started.

[00:00:27] Welcome back to the Back on Track: Achieving Healthy Weight Loss podcast. I'm your host, Dr. Alicia Shelly. And today we are talking about something I think we need to discuss much more often when we talk about weight loss.

[00:00:42] That is muscle. So when you are trying to lose weight, most of us have been conditioned to focus on one number, the number on the scale. You step on the scale, you lost five pounds. Great. You lost 10 pounds. Even better. But here is the question I want you to start thinking. What did you actually lose? Was it fat? Was it muscle? Was it water?

[00:01:09] And perhaps an even more important question is, are you becoming healthier and stronger as you lose weight or simply just lighter? This conversation has become especially important in the era of GLP-1 medications like semaglutide or Wegovy and tirzepatide or Zepbound because people can now achieve substantially greater amounts of weight loss than we routinely saw with older obesity medications.

[00:01:39] So today we're going to talk about muscle loss, sarcopenia, GOP-1 medications, protein, strength training, and what you can actually do to protect your muscle while losing weight. Now, let's talk about what is sarcopenia. You may have heard the word sarcopenia, especially in passing. Traditionally, we think about sarcopenia in the context of aging.

[00:02:07] It refers to a progressive loss of skeletal muscle. But importantly, it is not just about muscle mass. Muscle strength and physical function matter too. Having less lean mass on a body composition scan does not automatically mean someone has sarcopenia. But we also care about how that muscle functions. Like, for example, can you get out of the chair easily or do you have to hold on to the sides to stand up?

[00:02:37] Are you able to climb stairs? Or is it like your legs start to get weak as you climb stairs? Can you carry your groceries? Can you maintain your balance? How is your grip strength? That is why when we talk about healthy weight loss, we should not focus just exclusively on pounds. We want to lose excessive body fat while preserving as much of our muscle strength and physical function as possible.

[00:03:04] So, the next question is, do you lose muscle when you lose weight? Here is something that sometimes gets lost in the headlines. Muscle and lean mass loss are not unique to GLP-1 medications. When people lose a significant amount of weight, whether through calorie restriction, bariatric surgery, lifestyle interventions, or medications, not everything they lose is fat. Some of the weight can come from lean mass or muscle mass.

[00:03:31] And that does not mean weight loss is unhealthy. And it certainly does not mean we should avoid treating obesity. It means we need to think about the quality of the weight loss, not simply the quantity. This is especially relevant with newer medications because we are seeing levels of weight reduction that we would have been difficult to achieve with medications just a decade ago. And the question is no longer simply can we help someone lose 15 to 20% of their body weight.

[00:03:59] Now we can also ask how do we make sure that weight loss produces a stronger, healthier person? And that the weight loss that they lose is not muscle, but mostly body fat. So, do GLP-1 medications cause muscle loss? This is where I want to clear up some misinformation. You may see headlines that GOP-1 medication causes muscle wasting. This is an oversimplification.

[00:04:24] When they've done body composition studies with GLP-1 based therapies, it shows that not only fat mass loss, but also lean mass can decrease during substantial weight loss. When we look at tirzepatide or Zepbound, 75% of the weight loss was body fat and 25% was lean mass.

[00:04:46] And even the same with the GOP-1, I want to say average is 60% and it was a little over 60% and approximately 30%. So, needless to say, there is some lean mass that is being lost, but mostly it's body fat that is lost. And so, lean mass includes muscle, but also can include water, organs, connective tissue, and other nonfat tissue.

[00:05:12] So, we cannot assume that every pound of lean mass loss represents a pound of skeletal muscle loss. At the same time, muscle preservation is a legitimate clinical concern. The goal is not to make people afraid of GOP-1 medication. The goal is to say, if you are going to lose a significant amount of weight, let us be intentional about protecting your muscle while you do it. And so, who are the people who are most at risk?

[00:05:39] Muscle preservation matters for everyone, but there are certain people I think we should be even more careful about. And that includes people who are older adults, particularly people over the age of 65, people who already have low muscle mass to start, people who are sedentary, who are not moving around, people who are experiencing rapid weight loss, and people who are eating very little because their appetite has become significantly suppressed.

[00:06:05] We also need to pay particular attention to women during perimenopause and menopause because aging and hormonal changes can affect body composition and muscle. And this is where I sometimes see a problem with GOP-1 therapy because the patient tells me, Dr. Shelley, I'm not hungry anymore. And that may sound like a great thing. But when I ask them, what did you eat yesterday? I realized that they are barely eating. The goal of obesity treatment is to not starve.

[00:06:35] The goal is to be able to lose weight, but to not necessarily still be able to eat, but eat smaller portions. And so it is, and I'm always telling my patients, you need to eat. You need to eat. You need to make sure you get your meals in, even though you don't feel hungry. Because we want people to have enough appetite regulation to help you make healthy choices and achieve your goals while still providing your body with the nutrients that it needs. I tell them our bodies are like cars.

[00:07:05] They need fuel in order to run. And so we need to make sure we're giving it the proper nutrition so that it can work for us. If your medication suppresses your appetite so much that you cannot adequately nourish your body, that deserves a conversation with your healthcare professional. Maybe you need to come down on that dose so that you can actually start to eat and not necessarily go into starvation mode. And then guess what? Your body still holds on to the weight as well.

[00:07:33] And so this brings us to protein. Protein really, really matters. When you are losing weight, adequate protein becomes particularly important because protein provides the amino acids your body needs to maintain and repair muscle tissue. And when your appetite is significantly reduced, getting enough protein may become surprisingly difficult.

[00:07:55] Think about nutrient-dense sources of proteins such as eggs, Greek yogurt, cottage cheese, fish, chicken, turkey, beans, lentils, tofu, and other protein-rich foods. For some people, protein shakes or even protein-fortified foods can also help fill the gap. One strategy I often recommend when appetite is low is simply eat your protein first. If you become full quickly, you do not want to eat the most nutritionally important part of your meal still sitting on your plate.

[00:08:25] And so it's important that you eat your protein first, then your veggies, and then whatever starch is on your plate. Because you will get full fast and you need your protein most importantly. And the next question I get is, how much protein do I actually need? And for many adults who are actively losing weight and trying to preserve muscle, a reasonable goal is approximately 1.2 to 1.5 grams of protein per kilogram that you weigh per day.

[00:08:54] Also, that looks at your age, activity level, exercise program, and individual medical needs. Now, if you are somebody that has chronic kidney disease, then I recommend speaking with your doctor on how much protein you should be getting. Because it will be a little bit less when you have chronic kidney, especially if it's over stage 3. And I want you to make a difference. So let's do the math. Take your weight in pounds and divide it by 2.2 to convert your weight to kilograms.

[00:09:23] Then multiply that number by 1.2 to 1.5. And that will give you how many grams of protein you should be eating. And you would be 1.2 if you're not heavily active. And then you would be 1.5 if you are very active, going to the gym, you know, 4 to 5 days a week. Then you really need to be eating more protein with that much activity. So, for example, if you weigh 180 pounds, you divide 180 by 2.2, you get approximately 82 kilograms.

[00:09:53] Now multiply 82 by 1.2, especially if you're just doing light activity. That gives you approximately 98 grams of protein per day. So if we multiply 82 by 1.5, if you're heavily active, then that's approximately 123 grams per day. So your range will be roughly 98 to 123 grams per day, depending on how physically active you are. And if you are doing more regular resistance training, then aim towards a higher grams of protein.

[00:10:22] Now this is not one size fits all again. You know, protein can vary. People with certain medical conditions will need to talk to their doctor about that or to a registered dietitian. And the other thing is don't try to eat all your grams of protein in one meal. So don't do 100 grams at dinner. Try to spread your protein throughout the day. Think protein at breakfast, protein at lunch, protein at dinner, and protein-rich snacks when appropriate. Now here's the part I really want you to remember.

[00:10:51] Eating protein alone is not enough. Protein provides the building blocks. But your muscle also needs a reason to stay. And that reason is resistance training. Walking is wonderful. Running is wonderful. Cycling and swimming are perfect. Cardiovascular exercise has tremendous health benefits. But if your goal is specifically to preserve muscle during significant weight loss, we need to talk about resistance exercise. That can mean lifting weights.

[00:11:20] That can mean resistance bands. That can mean weight machines. It can mean appropriately programmed body weight exercise. And no, you don't need to become a bodybuilder. You simply need to challenge your muscles consistently. Think about it this way. Protein gives your muscles the building blocks that it needs. Resistance training gives your body a reason to keep that muscle. And the one thing I want to also mention that having that muscle is important.

[00:11:48] Muscle actually burns more calories at rest than body fat does. And therefore, if you're trying to increase your metabolism, protein toning that muscle will help you tremendously and keep your metabolism and your energy expenditure higher. So, let's stop measuring success with only the scale. I want us to broaden how we define weight loss. If someone loses 50 pounds, that number alone does not tell me everything I want to know.

[00:12:16] I also want to know how was your waist circumference changed? How was your body composition changed? Are you stronger? Can you walk further? Can you get off the floor more easily? Are you able to climb stairs without becoming exhausted? Are your blood pressure, blood sugar, cholesterol, sleep apnea, or other obesity-related conditions improving?

[00:12:36] And depending on the individual, we may use tools such as the bioelectric impedance that tells you these are scales that you can get on. You can get easily from, you know, your local stores, which look at your body fat, body water, and weight as well. Or if you have a company or school near you that does the DEXA scan to look at body composition, definitely these are tools that we can use to see where you are.

[00:13:06] And it's helpful because it kind of gives us a good measure. And even if the bioelectric impedance scales, that is what we have. And so you can do that from home. And as long as you know where you started from, you can actually trend how well you're doing as far as, am I losing muscle? Am I building muscle over time? You don't have to go get the expensive DEXA. Because ultimately, the scale is just one measurement. It's not the entire definition of health.

[00:13:35] And that actually leads beautifully into another episode, which we'll bring later on this month, about whether we're measuring obesity or wrong. And this is where the science is going next. There's another reason that this topic is so timely. Researchers are now asking whether future obesity treatments can help people lose significant amount of fats while preserving more muscle. And so one of the areas being studied are medications targeting that pathway, including the myostatin areas.

[00:14:04] And I will talk about the myostatin inhibitors in another episode in the future. But we need to look at how we can. And so this is also investigational, so it's not quite out there yet. But it's helpful to know that hopefully in the future, we may be able to block and preserve more muscle while we lose weight. So in conclusion, I want you to take away these five takeaway points.

[00:14:32] Number one, weight loss and fat loss are not exactly the same thing. Number two, some lean mass loss can occur with significant weight loss, regardless of whether you lose weight through lifestyle intervention, bariatric surgery or medications. Number three, if you are losing a substantial amount, make muscle preservation part of your plan. And number four, make sure you're getting adequate amount of protein.

[00:14:58] And for most adults, that can be between 1.2 to 1.5 grams per kilogram per day. And then five, don't forget the resistance training because you need to do that. So resistance training is imperative. And finally, and this is a bonus, stop allowing the scale to be your only definition of success. We do not simply want you to weigh less. We want you to be healthier. We want you to be stronger. We want you to maintain your independence. And we want you to move better.

[00:15:28] We want the weight you lose to translate into longer, healthier, more functional life and better quality of life. Because that's what successful obesity treatment should ultimately be about. So thank you again for joining me on the Back on Track Achieving Healthy Weight Loss podcast. If you found today's episodes helpful, share it with a friend. And don't forget to like and subscribe. And until next time, stay strong, stay committed, stay consistent. And remember, we are stronger together.

[00:15:57] And I'm Dr. Alicia Shelly, and I'll see you next time. Bye. Bye. Bye.