By Dr. Tara Altepeter
“It’s great that I’m losing weight, but am I losing too much muscle?”
This is a concern I hear commonly. You may have heard that muscle loss occurs in patients taking GLP-1 medications. Muscle loss does occur during weight loss, but the good news is there are things you can do to protect your muscle mass and strength while you are losing weight. Below I’ll discuss why muscle matters, what the research about muscle loss and GLP-1s tells us, and steps you can take to protect your muscle.
Why muscle matters
Muscles help you do the things you need to do every day – walking, climbing stairs, carrying a bag of groceries, etc. But did you know that muscle is also an important part of your metabolism?
Muscle is an active tissue. When you are moving your muscles, they take glucose (sugar) directly from the bloodstream and use it to fuel your movement. This in turn helps maintain stable levels of blood sugar. Muscle also burns more calories than other tissues in the body – so having healthy muscle mass helps to support your metabolism and maintain your body weight long term.
What happens to muscle during weight loss
Any time you lose weight, whether from diet and exercise alone, weight loss medications like GLP-1s, or weight loss surgery, you will lose some muscle along with fat.
With GLP-1 medications, most of the weight lost is fat, but some is lean body mass, also called fat-free mass. Studies show that in patients using GLP-1 medications for weight loss, roughly 15-40% of total weight lost was lean body mass. Lean body mass also includes things besides muscle, such as water and organ tissue, so that number does not represent just muscle.
Some people are at higher risk of excessive muscle loss, including older adults and people who already have low muscle mass when they start treatment. For these individuals, particular care should be paid to strategies to maintain muscle mass during weight loss.
How to protect your muscle during weight loss
Evidence supports the following strategies to help maintain (and even build!) your muscle mass during and after weight loss.
- Strength training (2-3 days a week)
Resistance training is an important part of the treatment plan for all patients trying to lose weight. It doesn’t require an expensive gym membership or huge investment in equipment. Depending on your level of fitness / physical ability, strength training can include resistance bands, light weights, or your own body weight, like wall push-ups or chair stands.
- Adequate protein intake
Including a good source of protein at each meal can help ensure your body has the needed building blocks to support your muscle.
Your doctor will help you identify an appropriate protein goal. For most people, this is around 1.2g/kg of body weight. Certain medical conditions (like chronic kidney disease) can change this target, so check with your doctor for a personalized recommendation.
Divide your protein across 3 meals plus snacks, rather than eating it all in one sitting. High protein foods include lean cuts of meat, chicken, fish, dairy (Greek yogurt, cottage cheese, string cheese), tofu, beans, and lentils.
If your appetite is low on a weight-loss medication, it can be helpful to focus on eating your protein first. A daily protein shake or bar can also be added if you are unable to meet your protein needs just through your meals.
- Move a little every day
Walking and other aerobic activity complements strength training, to help maintain muscle mass and support your weight loss goals.
A real-world example:
A recent study followed 200 adults starting semaglutide or tirzepatide over 6 months. Participants were taught about strength training and the importance of dietary protein. In this cohort, patients lost an average of about 13% of body weight but only about 3% of muscle mass.
Individual results will vary, but it is encouraging to see more studies being conducted to evaluate strategies to help patients maintain muscle mass while undergoing treatment for weight loss.
How our practice supports you
Care in our practice is more than just a prescription. At each visit, Dr. Altepeter will discuss dietary strategies and a plan for physical activity that is personalized to your lifestyle, preferences, and individual level of fitness. Body composition assessment is offered at every visit, using a hospital-grade bioimpedance based body composition scan, which allows us to measure and track both fat loss and muscle mass over time.
Frequent visits allow us to make changes to the plan as soon as we identify they are needed.
Summary
The goal of metabolic care is more than just a lower number on the scale. Our program is designed to help you lose weight, maintain muscle mass, and improve your overall health.
If you are ready to get started, schedule an appointment today or book a free introductory call to learn more.
This post is for educational purposes and is not personal medical advice. Please consult your physician before starting a weight loss plan.