The Risk of Rapid Weight Loss and GLP-1 Related Muscle Loss in Surgical Patients

The opinions expressed in this article are solely mine. I am neither an MD nor scientists but I am an avid reader of health trends and scientific literature.

The rise and prevalence of obesity in America has been nothing short of a breathtaking crisis. Whereas not long ago, less than 2% of the adult population was obese, it is forecasted that by 2030, that roughly 50% of U.S. adults will have a BMI greater than 30 (the clinical threshold for defining obesity) and another 20-30% will be in the “overweight” category. When I read these numbers, I find myself having to look at them more than once just to grasp the reality that close to 80% of our population is overweight. The underlying reasons and drivers are as clear as day but that is not the focus of this article. I will cover that in another article as it's a big topic that requires multiple actors and for it to be treated as a national emergency and existential crisis.

There is enormous human suffering implied in the obesity growth chart below. Obesity is concomitant with other markers of health decline (e.g. diabetes, hyperlipidemia, hypertension, etc.) and a more rapid decline in overall health. It also comes at staggering costs to the individual afflicted and to society. For obese adults in the United States, annual healthcare costs are estimated to be around $1,900 higher per person compared to individuals with a healthy weight. For severe obesity (roughly 10% of the population), per capita costs can be even higher, with estimates exceeding $3,000 per year. That's more than half a trillion dollars per year as a nation. The costs are expected to continue to rise putting us in economic peril unless significant action is taken and more solutions brought to bear. Again, for another article in the near future.

In this article, I focus on obesity in the context of surgery. Why obesity presents significant challenges and risks as it relates to surgery and why rapid weight loss through severe caloric restriction and drugs like GLP1s can add to surgical risk if not managed thoughtfully through the lens of surgical readiness. Most surgeons that I speak with find this to be a conundrum that they have not solved. They are simply at a loss as to "where to send these patients."

The demand for surgical procedures is steadily rising worldwide, driven by factors such as aging populations and increased prevalence of chronic diseases. In the U.S. alone, the number of surgeries performed annually has grown significantly, particularly in areas like orthopedic, cardiovascular, and weight loss (bariatric) surgery. This rise is expected to accelerate over the coming decades as life expectancy increases, and technology advances, enabling more complex and preventive surgeries.

In recent years, medications like GLP-1 receptor agonists (e.g., Ozempic, Wegovy) have emerged as powerful tools for weight loss and managing type 2 diabetes. While these drugs are generally well-tolerated and effective, they come with specific risks that require careful consideration, especially for individuals preparing for surgery. One significant risk associated with GLP-1 use and rapid weight loss is muscle loss, which can compromise a patient's physical resilience and significantly impair recovery. Below I discuss the reasons why muscle loss from rapid weight reduction, particularly in the context of GLP-1 use or radical diets and starvation, can be a serious issue for surgical patients. It is early to know what the downstream impacts are going to be, but I am predicting that outcomes will suffer.

Muscle Mass and Surgical Outcomes

The correlation between muscle mass and surgical outcomes is well-documented in medical literature. Muscle tissue plays a critical role in stabilizing the body and aiding in recovery after surgery, serving as a metabolic reserve (particularly for key amino acids) that the body can draw upon during periods of stress, like surgery. Low muscle mass has been shown to be a predictor of worse surgical outcomes, including:

• Increased Complications: Patients with low muscle mass are more prone to complications such as infections, wound healing issues, and longer hospital stays.
• Prolonged Recovery Times: Recovery from surgery requires physical strength and endurance. Patients with low muscle mass may struggle to regain their functional abilities, leading to a prolonged recovery.
• Higher Mortality Rates: Some studies suggest that low muscle mass is associated with increased mortality following surgery, likely due to the body's decreased ability to cope with surgical stress and inflammation.
• Increased Infections: Patients with low muscle mass may have a weaker immune response, making them more susceptible to infections, which is a significant concern following surgery.

Given these associations, preserving muscle mass before a surgical procedure is crucial. However, the rise in popularity of GLP-1 receptor agonists, often used for weight loss, presents a new challenge for maintaining muscle mass.

GLP-1s and Muscle Health

GLP-1s work by stimulating insulin release, slowing gastric emptying, and reducing appetite, leading to significant weight loss.

While this weight loss can bring substantial health benefits, it is often associated with both fat and muscle loss. For surgical patients, the muscle loss aspect of GLP-1 medications can be problematic for several reasons:

• Unintentional Muscle Loss: Unlike traditional weight loss strategies that may prioritize muscle preservation, GLP-1 receptor agonists do not inherently distinguish between muscle and fat tissue. Consequently, patients may lose muscle mass without realizing it.
• Reduced Physical Function: Muscle loss from GLP-1 use can lead to decreased strength and physical function. For surgical patients, this loss in function can make it difficult to perform basic tasks, which are essential for post-operative mobility and reducing the risk of complications like blood clots.
• Nutritional Deficiencies: Reduced appetite associated with GLP-1 drugs can lead to lower protein intake, exacerbating muscle loss and leaving surgical patients in a compromised state before undergoing procedures.

Rapid Weight Loss and Its Impact on Muscle Health

For many patients, weight loss before surgery is encouraged, especially when obesity is a contributing factor to surgical risks. However, rapid weight loss—often achieved through GLP-1 medications—can lead to the loss of muscle mass alongside fat. This speed of weight reduction poses several challenges:

• Catabolic State: Rapid weight loss can place the body in a catabolic state, where it breaks down both fat and muscle for energy. This state depletes muscle reserves that are essential for recovery and tissue repair following surgery. The last thing we want is for a patient to go into a surgery, which has significant metabolic demands, in a catabolic state.
• Nutrient Shortages: Fast weight loss can result in inadequate nutrient intake, which is necessary for muscle maintenance. Macronutrients like protein and amino acids are critical for muscle preservation, yet they are often reduced during low-calorie or low-appetite periods associated with rapid weight loss.
• Loss of Mobility and Balance: Muscle loss from rapid weight reduction can impair mobility and balance, making it difficult for patients to engage in early mobilization post-surgery, a factor that is critical for recovery and preventing post-operative complications.

We already know from published studies, that certain orthopedic procedures can compromise muscle. For example, in hip and knee joint replacement surgery (while miraculous in its ability to restore function and reduce pain), can have a detrimental effect on type 2 muscle fibers. Type 2 fibers, also known as fast-twitch fibers, are responsible for quick, powerful movements and play a significant role in stabilizing joints and aiding in activities that require strength and speed. Following joint replacement surgery, patients often experience muscle atrophy and a shift in muscle composition, with a notable reduction in type 2 muscle fiber function. How is this impacted when a patient is catabolic going into surgery as a result of GLP-1s? This has yet to be studied and remains to be seen. Again, I'm predicting that it won't be favorable.

Weight Loss with Surgical Optimization with Nourished by Mend

While GLP-1 receptor agonists offer promising results for weight loss and glycemic control, they can present unique challenges for surgical patients due to their potential for muscle loss. Given the critical role of muscle mass in surgical recovery, patients on GLP-1 drugs or experiencing rapid weight loss should work closely with their healthcare teams to prioritize muscle preservation strategies.

At Mend we think it’s incredibly important to manage weight loss effectively and pay careful attention to the modifiable risk factors and optimizing those before a patient is surgically ready. Our weight loss and BMI management programs are embedded in surgical readiness precision care pathways so that we are ultimately driving towards the patient being in a sound metabolic state and prepared for the demands of surgery to have good surgical outcomes. This is a very unique approach and unique capability in the world of weight loss.

The Nourished by Mend Program is a science-backed program designed to support healthy weight loss while preserving muscle mass, which is essential for metabolic health and physical resilience. Using a combination of Mend’s clinically proven nutritional supplements (which mitigate muscle atrophy and damage) and tailored lifestyle guidance, the program helps users achieve sustainable weight loss by focusing on high-quality nutrition, balanced macronutrient intake, and muscle-supportive components. Key elements include supplements formulated to reduce inflammation, enhance muscle recovery, and improve overall energy, promoting effective fat loss without sacrificing lean muscle.

This approach makes it particularly beneficial for individuals using GLP-1 medications, who may experience muscle loss during weight reduction. The program is a holistic, structured plan that emphasizes long-term health and vitality over rapid, unsustainable weight loss.