Coming Tomorrow Morning Does a weight-loss plateau mean your GLP-1 receptors have become desensitized? John separates cellular receptor biology from whole-body weight regulation and compares semaglutide, tirzepatide, and investigational retatrutide. We examine appetite suppression, food noise, gastric-emptying tachyphylaxis, metabolic adaptation, switching therapies, and what the clinical evidence can—and cannot—tell us. A plateau is real. “Receptor burnout” is a much bigger claim. Educational only; not medical advice.

John what do you know about this two Flgr242 for muscle building Klotho for kidney disease Thank you

Precursors Explained Most people who spend money on NAD+ injections believe they are delivering NAD+ directly to their cells, and that the injection is more powerful than a pill because it skips digestion and goes straight into the bloodstream. The first part of that is true. The second part is where the logic breaks down. To understand why, you need a map of how NAD+ actually works in the body, because without that map, the argument for injections sounds perfectly reasonable. NAD+, which stands for nicotinamide adenine dinucleotide, is a molecule your cells use as a kind of electron shuttle, picking up and dropping off charged particles to power the energy production happening inside your mitochondria. Every cell in your body needs it constantly, and your total NAD+ supply turns over multiple times per day, meaning your body is continuously breaking it down and rebuilding it. The problem is that NAD+ is a large molecule, and large molecules cannot pass through cell membranes the way small ones can. The membrane is a selective barrier, and NAD+ does not have a direct transport mechanism that lets it cross intact into the interior of the cell where it is actually needed. This is where the injection story gets complicated. When you inject NAD+ into your bloodstream, the molecule circulates. But to get inside a cell and reach the mitochondria where it will be used, it cannot enter as NAD+. Instead, it gets broken down outside the cell into smaller components, specifically into something called nicotinamide, which is a simpler building block that cells can actually absorb. Once inside, the cell reconstructs NAD+ from that raw material through a series of enzymatic steps. The molecule you paid to inject was disassembled before it was used. What your cell actually worked with was the breakdown product, not the original compound. This is not a flaw in your biology. It is the system working correctly. Cells maintain tight control over what enters them, and they have sophisticated machinery for building NAD+ internally from precursors. The same machinery runs whether the precursor came from an injection, a supplement, or food.

As I’m sitting here sipping my coffee and planning new episodes for the pod, I started wondering where you guys are sourcing your peptides. Obviously, I use Offline and Premier Pharmacy for mine. So, where do you get yours? Are there other companies I should check out? Have you had any issues with those vendors? I am truly curious. John

I know all of you definitely do...So do I, but many people are asking the question and this is my answer. My honest opinion: not everyone should. Peptides are not a health requirement, and the goal should never be to become a “peptide user.” The goal is to improve a defined health problem, symptom, or functional limitation. Some people may have a legitimate reason to consider a peptide-based therapy—such as obesity, metabolic disease, an injury, loss of function, or a diagnosed medical condition. But the decision should start with the problem, the evidence, the risks, the regulatory category, available alternatives, provider involvement, monitoring, and an exit strategy. In this episode, I break down the seven questions you should ask before considering any peptide. I also explain when the Top 11 Peptides episode and the individual Peptides Explained deep dives can help you understand the compounds relevant to your situation. The goal is not peptides. The goal is better health and better decisions. #PeptidesExplained #PeptideScience #Peptides #GLP1 #WeightLoss #InjuryRecovery #MetabolicHealth #HealthEducation #ClinicalResearch #LongevityScience