The Medical Advisor

Home › GLP-1 Hub By Dr. Frank Yap, MD | One Day Media Network | Published October 13, 2026 | Last updated: October 13, 2026 | Purpose: evidence and safety education, not individual medical advice Quick Answer As of October 2026, the FDA has approved two GLP-1 weight-loss pills, oral Wegovy (semaglutide 25 mg, December 2025) and Foundayo (orforglipron, April 1, 2026), alongside weekly injections such as Wegovy, Zepbound, Ozempic and Mounjaro. Retatrutide and CagriSema are not approved in the US. Compounded and gray-market GLP-1 products are not FDA-approved. Use a licensed prescriber and a regulated pharmacy. On this page Which GLP-1 medicines are approved in October 2026? Are GLP-1 pills as effective as injections? Retatrutide and CagriSema: what is known so far? Safety and side effects: what should patients know? Compounded, gray-market and research peptides: what are the risks? How strong is the evidence? (CEBM grades) Where to start: the complete GLP-1 evidence library Using...

GLP-1-based medications have changed the treatment of obesity by making substantial, sustained weight loss possible for many people. But as these medicines become more widely used, another question has become increasingly important: How much of the weight lost on a GLP-1 drug comes from muscle or other lean tissue—and can that loss be minimized? The evidence shows a nuanced answer. People taking semaglutide, tirzepatide and related incretin-based medicines generally lose much more fat than lean tissue . At the same time, absolute lean mass usually falls during substantial weight loss. Importantly, lean mass is not the same thing as skeletal muscle : DXA-based “lean mass” also includes water, organs and other non-fat tissues. Therefore, a finding that lean mass decreased does not automatically mean that the same amount of skeletal muscle was lost. Recent 2026 meta-analyses suggest that roughly one-quarter to one-third of total weight lost with incretin therapy may be classified as lean ...