GLP-1 medications have changed the landscape of weight loss for many women. For those struggling with obesity or long-term weight management, these medications can be an incredibly effective tool for improving health outcomes and creating meaningful fat loss.

At the same time, one concern continues to come up:
Will I lose muscle while taking a GLP-1?

It’s a valid question, and one worth understanding clearly.

Our Chief Science Officer, Natalie Suazo, shared that the conversation around muscle loss on GLP-1s often lacks nuance. While lean mass loss can occur during rapid weight loss, that does not mean GLP-1s are uniquely harmful to muscle tissue.

In fact, when researchers compare GLP-1-related weight loss to traditional diet-induced weight loss, the amount of lean mass lost appears to be fairly similar.

The more important question is not whether muscle loss can happen—it’s how to minimize it.

The good news? We already know what works.

Why Muscle Loss Can Happen During Weight Loss, Even Without a GLP-1

Any time you lose a significant amount of body weight, some lean mass loss is expected. This is true whether the weight loss comes from dieting, bariatric surgery, GLP-1 medications, or a combination of methods.

GLP-1s can increase that risk simply because they often create a large calorie deficit without much effort. Appetite decreases, portions get smaller, and many people begin eating substantially less than before.

While this can accelerate fat loss, losing weight too quickly—or without supporting your body properly—can make it harder to preserve muscle mass.

1. Avoid Losing Weight Too Quickly

One of the most effective ways to preserve lean mass is to keep your rate of weight loss moderate rather than aggressive.

Natalie recommends aiming for roughly 0.5–1% of body weight per week. For instance, a 100lb female should lose between half a pound and one pound of weight per week. That pace is fast enough to make progress while still giving your body a better chance to retain muscle tissue.

While it may be tempting to push for the fastest possible results, especially when appetite is low, more aggressive weight loss is not inherently better. In many cases, slowing down slightly improves body composition outcomes.

2. Prioritize Protein Intake With Your GLP-1

Protein becomes even more important when using a GLP-1. Because these medications reduce appetite and slow gastric emptying, many women unintentionally under-eat protein simply because they’re eating less overall.

Natalie recommends targeting at least 1.0–1.2 grams of protein per kilogram of body weight per day. For example, this means that someone weighing 100lbs (45kg) should eat no less than 45 grams of protein each day. And in some cases, even more may be beneficial depending on activity level and goals.

If appetite suppression is significant, tracking protein intake temporarily can help ensure you’re not consistently falling short.

Many women assume that “eating less” automatically means “better results,” but if protein intake drops too low, your body has fewer signals and fewer building blocks to maintain muscle tissue during weight loss.

3. Resistance Training Is Non-Negotiable

If preserving muscle is a priority, resistance training matters significantly.

One of the biggest limitations in many GLP-1 clinical trials is that participants often did not follow structured resistance training programs. That means the muscle-loss outcomes reported in research may overestimate what happens when proper strength training is included. The evidence is clear: resistance training is one of the most powerful tools we have for preserving, and even building, muscle during fat loss.

Natalie highlights several practical takeaways from the latest ACSM resistance training guidance:

Weekly Training Volume Matters Most

For maximizing muscle retention and growth, aim for approximately 10+ hard sets per muscle group per week. This can be spread across multiple workouts.

Train With High Effort

You do not need to take every set to absolute failure, but you should be getting close. The key is challenging the muscle enough to create a stimulus for retention.

Load Matters Less Than You Think

Both heavier and lighter weights can be effective for building or maintaining muscle as long as effort is high. That means you do not need to train with maximal loads to preserve muscle.

Frequency Is Flexible

Training frequency matters less than many people think. Whether you lift:

• 2 days per week
• 4 days per week
• Or even 1 day per week consistently

What matters most is accumulating enough quality work over time. In other words, the “best” program is the one you can actually stick to.

The Bottom Line

GLP-1 medications are not inherently muscle-wasting drugs.

For many individuals, they can be life-changing tools that improve body composition, metabolic health, and quality of life.

But like any weight loss method, they should be paired with intentional habits if the goal is to preserve lean mass.

According to Natalie, the three biggest priorities are straightforward:

1. A slower, controlled rate of weight loss.
2. Adequate daily protein intake.
3. Consistent resistance training.

When those fundamentals are in place, you dramatically improve your odds of maintaining muscle while losing body fat.

Weight loss is not just about seeing the scale move; weight loss is about improving the quality of the weight you lose. And preserving muscle along the way is one of the best things you can do for your metabolism, strength, and long-term health.

Looking for more guidance on your GLP-1 weight loss journey? Apply HERE to work with one of our coaches!