Can GLP-1 Weight Loss Drugs Give Athletes an Unfair Advantage?

The rise of GLP-1 medications, such as Wegovy and Mounjaro, has sparked discussions about their potential impact on athletic performance. Initially developed for weight loss and the management of type 2 diabetes, these drugs have gained attention from both the public and professional athletes, including tennis star Serena Williams. While Williams claims increased energy and improved physical well-being since using GLP-1s, experts are weighing the possible advantages and disadvantages these medications may pose in a competitive sports environment.

Dr. Sergio Guiteau, a board-certified family and sports medicine physician, points out that GLP-1s can enhance insulin resistance and body composition, leading to weight loss and potentially improved energy levels. He considers these benefits might provide some competitive edge, although not as pronounced as traditional performance-enhancing drugs (PEDs). The World Anti-Doping Agency (WADA) outlines criteria for substances classified as PEDs, including the ability to enhance performance, present health risks, or violate the spirit of sportsmanship.

While Dr. Guiteau believes GLP-1s meet the first criterion by potentially enhancing performance, he acknowledges that there is currently no evidence demonstrating a direct competitive advantage from these drugs. The use of GLP-1s could also lead to unintended consequences for athletes, especially regarding muscle mass. Karthik Achari, founder and CEO of PepMD, argues that a significant portion of weight lost while on GLP-1s—between 25% to 35%—is often lean muscle, which can be detrimental for athletes relying on strength and explosiveness.

Achari emphasizes that while a lighter weight may seem beneficial, losing muscle can hinder athletic performance. Additionally, elite athletes often require substantial caloric intake for their rigorous training and recovery processes. The appetite suppression and delayed gastric emptying caused by GLP-1s can complicate these nutritional needs, potentially impacting recovery and performance improvements.

Moreover, Achari notes the current lack of scientific research on GLP-1s in elite athletes, as most studies have focused on overweight or diabetic populations. He suggests that any observed benefits in athletes like Williams may stem from general weight loss and improved fitness levels rather than from the medications themselves.

Regarding WADA’s approach to monitoring GLP-1s, Achari supports their current strategy of surveillance without outright prohibition. This allows time for more data to emerge while providing a framework that distinguishes between medical and performance-driven uses of the drugs. Athletes with legitimate medical needs differ significantly from those seeking to use these drugs for competitive advantage.

Finally, Achari warns of the risks associated with obtaining GLP-1s through unregulated sources, which could expose athletes to contaminated or mislabelled substances. He stresses the importance of more focused research on healthy individuals to inform future regulations. As the debate continues, both athletes and sports organizations are urged to remain vigilant and informed, recognizing that the science surrounding GLP-1s and their role in sports performance is still evolving.