Luke Cox, Luke A. Turnock, Kim Akrigg, Timothy Piatkowski
Glucagon-like peptide-1 receptor agonists (GLP-1s) have rapidly transitioned from treatments for type 2 diabetes to widely used weight-loss medications. While compounds such as Semaglutide and Tirzepatide are clinically approved, the experimental triple-agonist Retatrutide has begun circulating through illicit online markets. Despite growing clinical research on their metabolic effects, little is known about how these substances are being incorporated into bodybuilding cultures. This study explores how GLP-1s, particularly Retatrutide, are discussed within online weight-training communities and how they are positioned relative to non-medical insulin use. Two netnographies of publicly accessible forums were conducted, analyzing 1,774 Reddit posts on Retatrutide and 12,392 posts from two major bodybuilding forums. Reflexive thematic analysis revealed that GLP-1s are framed as tools for improving insulin sensitivity, nutrient partitioning, and lean mass accrual, often promoted as a ‘safer’ alternative to insulin. These findings highlight risks related to unapproved compounds, misinformation, and polysubstance use within online enhancement communities.