One Day MD | Evidence-Based Wellness

Updated September 2026 GLP-1-based medicines have changed the treatment of obesity by making substantial, sustained weight loss possible for many people. But as the scale goes down, an important question follows: How much of the weight being lost is fat, and how much is lean tissue? This matters because long-term health is not determined by body weight alone. Preserving skeletal muscle, strength, physical function and nutritional adequacy is particularly important during substantial weight loss. The good news is that current evidence does not support the idea that GLP-1 therapies simply “eat away” muscle. Most weight lost with semaglutide and tirzepatide is fat mass. At the same time, measurable reductions in lean mass can occur, particularly during large or rapid weight loss. The most defensible strategy is therefore not to avoid effective obesity treatment, but to improve the quality of weight loss with adequate protein, progressive resistance training, sufficient nutrition a...

Updated October 1, 2026 Glucose-dependent insulinotropic polypeptide (GIP) was once overshadowed by GLP-1, but it has become one of the most important targets in modern metabolic medicine. The development of tirzepatide , a dual GIP receptor/GLP-1 receptor agonist, and the rapid development of retatrutide , a GIP/GLP-1/glucagon triple agonist, have moved GIP from a relatively obscure incretin hormone into a central part of obesity and diabetes drug research. At the same time, GIP biology is more complicated than the popular description of GIP as simply "the second hormone in tirzepatide." Researchers are studying both GIP receptor agonism and GIP receptor antagonism , two apparently opposite strategies that have both shown potential for improving metabolic outcomes. The mechanisms behind this paradox remain an active area of research. This GIP Academy explains what GIP is, how GIPR signaling works, how GIP differs from GLP-1, what is ...

Scientific Review by the Clinical Editorial Team  |  Published: November 2019  |  Last Reviewed: July 2026   |  Category: Regenerative Medicine | Evidence Review Quick Answer Stem cell research has grown to over 379,000 published studies on PubMed as of mid-2026, but the evidence is not uniform across conditions. Hematopoietic stem cell transplantation for leukemia and lymphoma is decades-old, FDA-licensed standard of care. A donor islet cell therapy, Lantidra , became the first FDA-approved cellular therapy for type 1 diabetes in 2023, and a stem-cell-derived successor, zimislecel , is now in Phase 3 trials. Everything else on this page — stroke, osteoarthritis, spinal cord injury, autoimmune disease, heart disease, autism, anti-aging, hair loss, kidney and liver disease, and back pain — remains investigational, with no FDA-approved stem cell product for these indications. The FDA has repeatedly warned that clinics marketing unapproved st...