Decoding Diabetes With Dr. Bob: GLP-1s, Muscle Loss, and the Next Frontier in Obesity Care

The GLP-1 revolution appears to be as strong as ever, but there will likely come a point when the general population begins to turn its focus away from the successes of these drugs and instead to their adverse effects and other challenges.

These include gastrointestinal side effects, high costs, limited access and availability, and unrealistic, quick expectations – all of which contribute to high dropout rates among users. In fact, studies have found that as many as 47-65% of people discontinue GLP-1 treatment after one year, with side effects being one cause. 

A common issue seen for people with diabetes and obesity who aren’t able to stay on GLP-1s long-term is weight cycling. Studies have found that when people regain weight after significant weight loss, they are more likely to regain proportionally more fat than muscle. As the pattern of weight cycling continues, a person will continue gaining fat mass rather than muscle.

Another major concern regarding GLP-1s is the issue of muscle loss. Losing muscle mass occurs with all methods of weight loss, whether it’s diet and exercise, bariatric surgery, or medication. But the broad success of GLP-1s like Mounjaro and Ozempic for weight loss is pushing this side effect to the forefront. 

Muscle loss: The disconnect between healthcare providers and patients

When I spoke at the Obesity & Weight Loss Drug Development Summit in 2o25, I surveyed an audience of experts on what they believe are the greatest unmet needs for people with diabetes or obesity trying to lose weight. Muscle preservation was consistently noted as number one.

Patients, on the other hand, would likely disagree. I have treated hundreds of people with GLP-1s and never had anyone say, “Doc, I feel weaker.” And when I have been purposefully asking people if they’ve noticed any differences in their strength, they say it’s better – even if a rigorous muscle strength test might suggest otherwise. Why might this be the case? Perhaps with weight loss, there is also less mass to carry around; ergo, they feel increased strength.

Is muscle loss on GLP-1s really a problem?

Muscle strength has been linked to better health outcomes long-term, yet GLP-1s, which diminish muscle strength, have also been shown to improve health outcomes long-term – for example, lowering the risk for heart and kidney disease.

So, is muscle loss really a problem? We don’t know yet. If we can show with evidence that, for example, older adults who have lost muscle mass are falling more than those who have not, that would be an observable clinical consequence of muscle loss to establish it as a significant issue. Essentially, we need functional data (i.e., patient-reported outcomes) to better understand the impact of muscle loss. 

How to keep muscles healthy

While researchers work on understanding the clinical implications of muscle mass loss, what can people taking GLP-1s do in the meantime? 

Nutrition: Protein, protein, and more protein

Protein intake is essential for preserving muscle mass, given that proteins are the fundamental building blocks of muscle. The recommended daily protein value is 0.8-1.5 g/kg/day. That means, for example, a person who weighs 220 pounds should get 80 grams of protein a day. The upper end of the range applies more for older adults who face age-related muscle challenges, while the lower end is meant more for younger adults.

For individuals on GLP-1s, meeting this protein goal can be more challenging since they may have less of an appetite. Therefore, they may need supplements like a high-protein, low-fat nutrition shake to meet this need.

Strength training

Protein intake alone, however, is not sufficient to protect muscles. Exercise, especially strength training (also called resistance training), is also crucial.

Strength training is more important for building and maintaining muscle than other forms of exercise, such as cardio, which mainly improves endurance and cardiovascular health. Strength training, on the other hand, directly targets muscles. Building more muscle also increases metabolism, allowing for more long-term fat loss.

Simple, accessible forms of strength training are sufficient. It’s not necessary to have a gym membership or a whole set of weights at home. Exercises that use an individual’s body weight (e.g., pushups, planks) work just fine. Resistance bands are also a relatively cheap option for strength training.

Another selling point for strength training, beyond muscle preservation, is increasing lifespan. Considerable data support this, with a meta-analysis finding that an hour of resistance training a week lowered mortality risk by 27%, making it equally as effective as quitting smoking or taking medication.

Last year, I found myself in Los Angeles speaking at the Connected Health & Fitness Summit. I was there to speak on GLP-1s, as many boutique fitness organizations and larger companies (e.g., SoulCycle) were interested in learning more about these therapies. Specifically, they were keen on understanding how to be part of the patient care team, and I suggested that they could make a significant impact in promoting strength training.

Since that conference, I have done podcasts to spread the word about strength training. There is now a GLP-1 Exercise Specialist Certification with the National Exercise & Sports Trainers’ Association and a continuing education program on weight loss medications for fitness and wellness professionals with the National Academy of Sports Medicine.

That said, insurance coverage for fitness coaches is still lacking. Interestingly, fitness coaches are where chiropractors were about a decade or two ago in limited payer coverage, despite compelling data. Most chiropractors now can offer their services and get reimbursed, perhaps because more evidence has demonstrated their effectiveness. It would be great to see the same happen with fitness coaches.

Muscle-preserving therapies and newer agents

Besides using nutrition and exercise for muscle mass, other drugs are being developed to achieve the same end. Several “stars” emerged at ADA 2025, such as bimagrumab, which is currently being tested in clinical trials. With this pharmacological approach to muscle preservation, we’re likely to see a combination drug for weight loss and muscle preservation in the future.

All things considered, the safety bar will be high, and these newer agents will be scrutinized, especially considering that GLP-1s already come with decades of safety data.

The FDA’s draft guidance released in 2025 requires new drug developers to have baseline and follow-up measurements of body composition using DXA (an X-ray used for measuring bone density) in clinical trials. This is an important shift, demonstrating the FDA’s recognition that muscle mass loss matters, even if we are still lacking patient-reported outcomes.

Concluding thoughts on muscle preservation

If you are a healthcare provider, emphasize the importance of muscle mass preservation to your patients taking GLP-1s, and encourage them to engage in strength training and get adequate protein. 

Understandably, this can feel like a lot to ask of healthcare providers, who are already pressed for time during visits and may only see their patients once every six months. This is where digital health and connected diabetes care can be leveraged (e.g., regular text message reminders). Plus, dietitians, certified diabetes care and education specialists, and perhaps fitness coaches could all be great, untapped resources.

As for who this issue may apply most to, older adults are at greatest risk for the potential consequences of muscle mass loss (e.g., falls), given naturally lower muscle reserves and age-related declines in strength. Preventing muscle mass loss in this population is not easy, but doable with the right tools. 

While access to nutritious food options is often cited as a barrier to a healthier diet, the reality is that effective resources are being underused. For example, 59% of adults ages 50 and older who are eligible for SNAP do not participate in the program, which allows participants to purchase protein-rich foods such as meats, poultry, fish, and seafood. For people who live in food deserts or have mobility issues, many online food delivery programs take SNAP.

The takeaway is that muscle preservation is critical to long-term health and quality of life for people with diabetes and obesity – it’s time for healthcare providers and researchers to act to help ensure people are getting the best out of their treatments.

The information and insights in this column are adapted from an original Closer Look column, published by Close Concerns. Written by Dr. Bob and Elaine Young, this column was originally designed for clinicians, researchers, and professionals working in diabetes and obesity care and has been adapted for diaTribe audiences.

Read more installments of Decoding Diabetes With Dr. Bob here:

• Meet Dr. Bob
• Diabetes and Mental Health
• Automated Insulin Delivery