Katie Mullen breaks down peptides as short chains of amino acids that send messages through your body, then maps six categories: repair, weight loss, growth hormone, longevity, skin, and brain function. She notes that peptides amplify healthy habits but can't fix a bad lifestyle, and distinguishes injectables from over-the-counter topical serums.
If you've been hearing the word peptides everywhere and just kind of nodding along with no real idea what it means, here's the one-sentence version: peptides are tiny messengers that your body already makes to tell itself what to do. That's it. Everything else is just details. But that probably still means nothing to you, so let me try to help it make sense. Hey, I'm Katie. If you keep hearing about peptides and have no idea where to even start, you're in the right place. And today we're starting with the most basic question there is: what even is a peptide? So a peptide is just a short chain of amino acids. I know that still sounds like science class, so let me try to normalize it. Amino acids are the building blocks of a protein. You've heard that word your whole life. When you eat a protein, your body breaks it down into these building blocks and rebuilds them into whatever it needs. So if a protein is a full paragraph, a peptide is just a short sentence, a little message. Peptides are how your body sends instructions to itself. They're like the signaling molecules. Do this thing here, do that thing there. Your body already makes thousands of these on its own right now. This isn't some foreign lab Insulin is a peptide. A lot of the quiet little jobs that your body runs all day are peptides. So before we go near any of the stuff that people hype up online, I just wanted that to land. Peptides aren't this new exotic thing. You are full of them at this exact second. So if peptides have always been in our bodies, why does it feel like the word just came out of nowhere and now it's on every podcast, every Instagram reel, every TikTok? A few things hit at once. The, the big one is these weight loss injectables that everyone's been talking about for the last couple of years. These are like semaglutide, tirzepatide, and the new kid on the block, retatrutide. And that moment that those came on the market did something. For the first time, a huge number of regular people watched a peptide-adjacent thing do something super dramatic and super visible. And people went, wait, what else is out there? What else can these things do? And at the same time, the longevity and the biohacking world got really loud. The optimize everything crowd and wellness in general moved past just taking a multivitamin and hoping for the best. People want targeted wellness now, this specific thing for this specific goal, and peptides fit that mood perfectly. Then social media, like it does, blew everything up. So here's the reason this whole channel exists. This world is kind of gatekept behind a wall of acronyms and forums and people acting like you should already know all of this. So if you're just a normal curious person who isn't deep into like the Reddit forums, that's the gap that this channel fills. It is for beginners. Whoever you are, whatever you're curious about, you are welcome Here, we're going to figure it out. Now, the thing that confused me the longest, and once it clicked I felt so much better, is that peptides is not just one thing. It's a giant umbrella, and people lump totally different things together underneath it, which is exactly why it feels so overwhelming. Here's a rough map. You don't have to memorize it, just know that it exists and that there are different categories under the peptide umbrella. First, there's the repair and recovery bucket. This is like tissue, joint, and healing. You'll hear a lot about the peptides like TB-500, BP- PC-157. And then there's weight loss and metabolism, the body composition category that we just talked about. So that would be the big ones like semaglutide, tirzepatide, and then retatrutide is the new one that is currently going through FDA clinical trials. So then you have growth hormone support. So this is like recovery, lean muscle mass, and some sleep effects. So you'll hear peptides like tesamorelin, semorelin, CJC-1295, kind of like in those buckets. Then you have like the longevity cellular energy metabolism bucket. This is like the age slower, more energy bucket. But like, who doesn't want that? Here you'll have like MOTS-c, SS31, even like NAD+. Even though it's not a peptide, it does get categorized here like with B12. So then you have the pretty peptide category that's skin, hair, and more like aesthetic. So you have the big one is GHK-Cu. This is what they typically call the pretty peptide. And you'll see like KPV and glutathione in here as well for some anti-inflammatory and like skin skin effects. Topical KPV is an anti-inflammatory peptide that you'll see a lot in like creams. Same with GHK-Cu, they're in a lot of serums that you can buy over the counter, which is different to like the injectable peptides that we're talking about. And that is one delivery method of these types of peptides. Then you have brain, mood, and sleep peptides, which focus on calm and the rest and the brain focus side. And you'll hear peptides like Semax, Selank, oxytocin, And DSIP in here. And those are usually ones that focus on like mood regulation and sleep support. And there are a ton more, but those are like the basic categories that helped me wrap my brain around it all. We'll do a video on basically every one of these, but today I just wanted to give you the map of what the categories look like. And before we wrap for today, because I'd rather be the person who tells you than the person who doesn't, but peptides are not magic. The internet makes them sound like a cheat code, but in my experience, they're more of like an amplifier to the good habits that you're already doing. They can support something that you're already building, but they won't fix bad habits. Deep down, we know that no shortcut really does. So that's it for today. If this made the peptide world feel even a little less overwhelming, go ahead and hit that subscribe button and turn on notifications because I'm building this whole thing in order so you can just follow along from the beginning. So I'm so glad you're here. I hope you learned something, and I'll see you in the next one.
