This could be why your weight-loss medication isn’t delivering results

This material may not be published, broadcast, rewritten, or redistributed. ©2026 FOX News Network, LLC. All rights reserved. Quotes displayed in real-time or delayed by at least 15 minutes. Market data provided by Factset. Powered and implemented by FactSet Digital Solutions. Legal Statement. Mutual Fund and ETF data provided by LSEG. Fox News senior medical analyst Dr. Marc Siegel discusses the benefits and risks of GLP-1 medications on 'Fox & Friends Weekend.' The skyrocketing popularity of GLP-1 receptor agonists has transformed the weight-loss industry, but not all shots are created equal in terms of how they work. A study published in Nature investigated how genes affect the success of modern weight-loss drugs — specifically, GLP-1s like semaglutide and tirzepatide. In analyzing genetic data and self-reported weight loss from over 27,000 users, researchers pinpointed a specific variation in the GLP-1 receptor gene (GLP1R) that acts as a "booster" for the drug’s effectiveness. POPULAR WEIGHT-LOSS MEDICATIONS LINKED TO HIDDEN SIDE EFFECTS, STUDY FINDS Individuals carrying one copy of this variant lost an average of 1.6 pounds more than those without it, according to the finding