What is a Peptide, Really?

Recommended next listen: In Conversation: Daniel Tausan — Peptides, GLP-1s, and Stress

Peptides seem to be everywhere. They're discussed in conversations about healing, GLP-1 medications, hormones, healthy aging, and longevity—but if someone asked you to explain what a peptide actually is, could you?

After recording my conversation with Daniel Tausan, I realized we spent nearly an hour discussing what peptides do without ever stopping to answer that first, foundational question.

In this episode, we slow things down.

Rather than focusing on specific peptides or whether you should use them, we build a framework for understanding what peptides are, how they differ from proteins and hormones, and why scientists have become so interested in them over the past decade. More importantly, we'll explore a much bigger idea: your body is constantly communicating with itself through chemical signals, and peptides are one part of that remarkable conversation.

By the end of this episode you'll understand:

• What peptides actually are—and what they aren't

• How peptides relate to amino acids and proteins

• Why the word "peptide" doesn't tell you what something does

• Why scientists view peptides as biological signals rather than magic solutions

• Why understanding this changes the way we think about modern medicine

If you'd like to hear these ideas applied to healing, hormone production, GLP-1 medications, stress, and healthy aging, be sure to listen to my conversation with Daniel Tausan after this episode.

Uncommonly Remarkable℠ is a health and wellness show focused on understanding how the body works and how everyday choices shape long-term health.

I’m Artis Beatty, a doctor of optometry and Chief Medical Officer at MyEyeDr. While my professional background informs how I think, the perspectives shared here are my own.

Transcript

SPEAKER_00 0:04

This is uncommonly remarkable. Ladies, gentlemen, all you remarkable people, welcome back to the show. If you've listened to my conversation with Daniel Towson about peptides, you may have noticed something. We spent nearly an hour talking about why peptides have become one of the most exciting areas of modern medicine. We talked about healing, hormones, stress, healthy aging, GLP1 medications, and why these tiny biological compounds have generated so much interest over the last several years. But after listening back to that conversation, I realized we skimmed over a seemingly simple but pretty important detail. What exactly is a peptide? Now, maybe you already know the answer, but if you're like most of us when we first started reading about this topic, you probably came away understanding why people were excited without necessarily understanding what they were excited about. You hear words like amino acids, proteins, peptides, hormones, and enzymes used in the same conversation, and before long, it starts to feel like everyone else understands the language while you're still trying to figure out the vocabulary. So today I want to slow things down just a little bit. This isn't meant to replace that conversation with Daniel. In fact, I hope it does exactly the opposite. My goal is to build a foundation that makes that discussion and frankly several other episodes we've done on this show over the past year much easier to understand. Because once you understand what a peptide actually is, you begin to see biology a little differently. So let's start with the technical definition because on the surface, it's incredibly simple. A peptide is a short chain of amino acids. That's it. If you open a biology textbook, that's essentially the definition you'll find. But if I'm honest, I don't think that definition is very helpful. It's technically correct, but it doesn't answer the question most of us are actually asking. It would be a little bit like telling someone that a violin is a wooden instrument with four strings. While that's true, it doesn't explain why anyone would care about a violin or how it can make music that can move people emotionally. The definition isn't wrong, it's just incomplete. So maybe the question then isn't what is a peptide? The better question might be, where does a peptide fit into the way your body works? Once you answer that question, everything else starts to fall into place. Every protein in your body begins with amino acids. They're often referred to or called the building blocks of proteins, and that's a perfectly reasonable place to start. Think of amino acids as individual letters. One letter by itself doesn't communicate very much, but when you begin putting letters together, they become words. Put enough words together and you have a sentence. Keep going, and eventually you have an entire book. Your body does something remarkably similar because amino acids link together to form chains. When those chains are relatively short, we call them peptides. When the chains become much longer and fold into complicated three-dimensional shapes, we call those proteins. So think sentences versus words or phrases. They're not completely different things, they're different expressions of the same building blocks. I think that's where many of us get tripped up because we tend to think proteins and peptides belong in completely different categories when in reality they're actually part of the same family. A peptide isn't the opposite of a protein any more than a paragraph is the opposite of a book, it's simply smaller. But here's where this all starts getting interesting. Most people assume that the word peptide tells you what something does. It doesn't. It only tells you what it is. That's an important distinction because two peptides may have almost nothing in common except that they're both relatively short chains of amino acids. One may influence appetite, another may participate in healing, yet another may help regulate hormones or may be involved in how your brain communicates. Saying something is a peptide is a little like saying something is a vehicle. That could describe a bike, a pickup truck, it could describe an ambulance or an airplane. The word itself tells you very little about its purpose. So why has everyone suddenly become interested in peptides? The answer isn't because scientists recently discovered them, of course. Your body has been making peptides your entire life. What's changed is that we've become much better at understanding what individual peptides do and perhaps more importantly, recognizing that some of them act as remarkably precise biological signals. We often think of the body as a collection of organs. There's a heart, a liver, a brain, muscles, etc., but that's really looking at biology as if it were a collection of parts. Another way to think about the body is an enormous communication network. Every second of every day, cells are sending messages, receiving messages, responding to messages, and coordinating those responses with millions of other cells. Your body isn't simply built from tissues, it's built from information. That's why the conversation with Daniel kept coming back to one word: signal. Hormones are signals. Many peptides are signals. Your body is constantly gathering information, it's sending information and is responding to that information through chemical signals. So chemical signals are the body's form of internal communication. And if you think about chemical signals like communication, you stop asking, what does this peptide do? And you start asking, what conversation is this peptide participating in? That's a much more useful question because biology rarely works through a signal pathway. Instead, it's more of an orchestra. Millions of signals are being sent simultaneously, and some are becoming louder while some are becoming quieter, but they're all working together to maintain a remarkable balance that is our health. That's also why the idea of simply taking a peptide can be misunderstood. A peptide isn't magic, it doesn't override your biology. Most of the time, it's participating in the biology. In fact, it's encouraging, influencing, or amplifying a process that's already built into your body. That's very different from replacing that process altogether, and it's one of the reasons that conversations around peptides have become so exciting. Scientists are increasingly asking whether we can work with the body's own communication system instead of trying to overpower it. That was one of the themes Daniel kept returning to. Whether we were discussing healing, hormone production, or GLP1 medications, the conversation came back to the same idea. These biological signals create opportunity, but they don't eliminate participation. Your lifestyle, nutrition, exercise, and sleep still matter. The signal may help direct the process, but your body still has to do the work. So now we've answered the first question, we know what a peptide is. The second question is why that understanding changes the way we think about modern medicine. For decades, scientists have studied proteins because proteins do so much of the heavy lifting inside the body. They build tissues, transport oxygen, fight infections, and perform thousands of other jobs that keep us alive. But along the way, scientists began noticing something interesting. Sometimes it wasn't the entire protein that was responsible for a particular biological effect. Sometimes a relatively small section of that protein carried the instructions that they were looking for. Think about it like reading a great book. Sometimes a protein is like an entire chapter, but scientists eventually realized that one sentence inside that chapter was carrying the instruction that they were looking for. A large protein may contain a much smaller segment that carries a very specific message, and in many cases, that message comes in the form of a peptide. That's really what's changed over the last decade. Scientists didn't suddenly discover peptides. They've known about them for a fairly long time. What's changing is that we're finally beginning to understand the language they speak. Now, that's an important distinction because it's easy to hear all of this and conclude that peptides must be some new invention. And they're not. Most of the peptides people are talking about today already exist somewhere in the human body. The excitement comes from identifying them, understanding what message they carry, and asking whether that message can be used to help the body do something it was already designed to do. That idea is very different from simply replacing something that's missing. If you take testosterone as an example, because it's familiar to most people and one we discussed in the episode, one approach is to give someone testosterone directly. The hormone enters the bloodstream and the body responds to it. That's effective in many situations and absolutely has an important place in medicine. But another approach is to ask a different question. Instead of replacing the hormone, is there a way to encourage the body to produce more of its own? Those are two very different strategies, even if the goal is similar. That's one of the reasons peptides have attracted so much attention. In some situations, researchers are exploring whether it's possible to influence the body's own communication systems instead of bypassing them altogether. The same idea shows up in conversations about healing. If you've heard people talk about peptides for recovery after injury, it's easy to imagine them as some kind of biological supercharger. Maybe as though you take an injection and damaged tissue magically repairs itself. That's not really what's happening. Healing isn't one thing. It's inflammation, blood flow, connective tissue, immune cells, there's nutrition, movement, and of course time, and all of that is happening together. A peptide doesn't replace that process. At its best, it's participating in one part of that conversation. The same thing is true for GOP1 medications, which have become almost impossible to avoid over the last few years. We often talk about them as weight loss drugs, but that's probably an oversimplification. They work through signaling pathways that influence appetite, digestion, and ultimately behavior. They don't eliminate the importance of nutrition, movement, or sleep, they just change part of the conversation, making some healthy decisions easier than they were before. I think that's one of the reasons my conversation with Daniel resonated with me. No matter what example we discussed, healing, hormone production, GOP1 medications, even stress, we kept arriving at the same conclusion. Biology isn't looking for shortcuts, it's responding to information. Sometimes we can influence that information in meaningful ways, but we're still participating in the outcome. We don't stop exercising because a peptide exists. We don't stop paying attention to nutrition because medication helps regulate appetite. And we certainly don't stop sleeping because we found a better signal. We simply give our bodies another tool to work with. And maybe that's the biggest misconception surrounding peptides today. People often talk about them as though they're replacing healthy living when in reality they're most powerful when healthy living is already present. They're less like hiring someone to do the work for you and more like giving your body clear instructions while it does the work it was designed to do. And maybe that's really the lesson. It's easy to become fascinated by a new treatment, a new supplement, or a new medication. Medicine will continue to become more sophisticated, and that's something worth celebrating. But none of these advances replace the remarkable biology that's already inside you. Your body has always been communicating with itself. Scientists are simply getting better at understanding that language. And that may not sound like much of a difference, but I think it's an important one. It changes the way we think about health. Instead of asking how we can overpower biology, we're increasingly asking how we can work with it. I think that's a much more helpful way to look at the future of medicine. If today's episode gave you the vocabulary, my conversation with Daniel gives you the application. We spent nearly an hour talking about what this means for healing, hormone production, GLP 1 medications, stress, and healthy aging. I think you'll enjoy that conversation even more now that you've built this foundation. This is uncommonly remarkable.