Peptides are everywhere in longevity and functional medicine, but what does the law actually say? In this episode, Dr. Matt Kaeberlein breaks down what a peptide is and the complex regulatory landscape governing peptides in the United States, from FDA approval frameworks to the legal gray zones surrounding compounding pharmacies and unapproved substances. Drawing on the Federal Food, Drug, and Cosmetic Act and real-world enforcement cases, this episode offers a clear-eyed, non-judgmental examination of what is legal, what is tolerated, and what carries genuine risk for physicians, pharmacies, and patients alike. An essential listen for anyone navigating the rapidly evolving world of peptide therapeutics.