BPC-157, Thymosin Alpha-1, and TB4: What the Science Actually Says About the Peptides the FDA Banned

In this 2026 YouTube presentation, Dr. Aaron Hartman reviews several peptides that have been popular in functional‑medicine and anti‑aging circles but have faced increasing FDA restrictions after 2023. He begins with a brief call to subscribe, then systematically discusses each peptide’s discovery, biological mechanism, clinical applications, evidence base, safety profile, regulatory status, and practical considerations such as sourcing, dosing, and patient selection. Thymosin α‑1 – discovered in the 1970s, enhances T‑cell maturation, NK‑cell activity, and cytokine balance; approved in >35 countries for hepatitis B/C, cancer support, and immune modulation, but not FDA‑approved in the US due to lack of commercial sponsorship. Over 11,000 human subjects have been studied. FDA re‑classified it from Category 1 to Category 2 in 2020, effectively banning compounding pharmacies. Quality concerns arise from research‑grade imports, especially from China. Thymosin β‑4 / TB‑500 – a 17‑amino‑acid fragment of the full β‑4 peptide, discovered by the same group; regulates protein synthesis, cell migration, and tissue repair; used for musculoskeletal injuries, scar reduction, and pulmonary/renal fibrosis via TGF‑β1 modulation. Animal data are strong; a Phase 2 trial (2009) remains unpublished, highlighting publication bias. BPC‑157 – a 15‑amino‑acid peptide isolated from human gastric juice in the 1990s; promotes angiogenesis, nitric‑oxide modulation, growth‑hormone interaction, and barrier repair (gut, blood‑brain). Over 100 pre‑clinical studies and a 2025 systematic review of 544 papers; only one human intra‑articular knee trial. Considered GRAS and sold as a supplement, yet compounding pharmacies cannot legally produce it. Oral formulations lose potency compared with injectable routes. CJC‑1295 + Ipamorelin stack – synthetic GHRH analog (CJC‑1295) combined with a ghrelin‑mimetic (Ipamorelin) to stimulate pulsatile growth‑hormone release while limiting excessive, sustained elevations that could raise cancer risk. Discusses DAC (drug‑affinity‑complex) variants with 7‑day half‑life that may oversaturate receptors. Highlights benefits for tissue healing, sleep quality, and age‑related GH decline, while warning against high‑dose, long‑acting formulations. GHK‑Cu – a tripeptide‑copper complex discovered in the 1970s; stimulates collagen, glycosaminoglycans, nerve growth, and possibly normalizes tumor‑cell gene expression. Used topically in aesthetic medicine for skin rejuvenation, wound healing, and hair regrowth. Remains Category 1 (not banned). Overall peptide landscape & clinical integration – >7,000 known peptides, ~70‑80 synthetically accessible. Dr. Hartman stresses foundational health (nutrition, toxin removal, sleep) before peptide therapy, especially for patients >40 y. He advises against routine peptide use in teens/early‑20s, recommending investigation of underlying deficiencies first. The talk blends historical context, mechanistic insight, regulatory commentary, and pragmatic guidance for clinicians considering peptide therapy.
Chapters
Welcome back once again. I am super excited to keep on going forward with peptides. Today we're going to talk about thymosin alpha 1, TB4, Wolverine peptide, BPC. But a little bit of housekeeping first. Most people who are watching this, wherever you're watching this right now, aren't actually following or subscribed. So if you could subscribe below, that'd be super helpful. It just helps us know that one, what we're doing is helpful and also helps with us to make sure we're getting good information out there. So if you subscribe below, that'd be super helpful. And now let's get onto the rest of the peptides. So I want to talk about a couple of peptides that are super popular. But keep in mind, the peptides I'm talking about, functional medicine have been using for years, sometimes decades. But after 2023, the FDA has been cramping down on these. And there's been a big ban on and off since then. So let's talk about the science actually says. So first, let's talk about thymosin alpha 1. This is the immune modulator peptide. Okay. So how long has it been around? It was actually discovered in the 1970s by Alan Goldstein, his group at George Washington University. It was actually isolated from thymus tissue. And what, what it does, it actually trains your immune system. So you gotta realize this has actually been around for 50 years. It's approved for human use in 35 countries for hepatitis B, hepatitis C, cancer support. And a lot of European countries, when you, when you actually get cancer and chemotherapy, one of the side effects is your white count goes down. Thymosin Alpha 1 is actually used to help bump up your white cell count. So again, used in over 35 countries around the world. It's not currently approved in the United States for use, not because there's a lack of evidence, but because there's been no pharmaceutical companies invested enough to actually pay to get it approved. Not quite sure why that is. Utilized around the world, but that's just not happened here currently in the United States. There's been over 1,100 humans— I'm sorry, no, there's been over 11,000 human subjects studied in trials with thymosin alpha-1. So you can't say there's not evidence. You can't say it doesn't work because it's used literally around the world. So what does actually thymosin alpha-1 do? Enhances T-cell maturation and activation. Now, what does that mean? You know, our thymus gland, when you're young, it's really big. And we get to— I'm 53 now. And as you get older, as of the recording of this, it actually shrinks over time. The T-cell activation in your thymus actually helps you develop an immune system against new exposures, new infections. This was a big deal during COVID because it was something totally new. And younger people who actually had an active thymus did better than older, older people who don't. It's also one of the reasons why when you get to be older, typically over 70, you're more prone to die from certain infections because you don't have the ability to adapt your immune system like you do when you're 2, 3, or 4. At the same time, if you're a newborn, you're like a month old, because you haven't been exposed to anything and haven't developed an immune system to date, your thymus is super big and making lots of antibodies, which is— that's also one of the reasons why colostrum's important when babies are born because through the colostrum and then through actually the mother's blood when the baby's inside the mom, She actually passes on her immune system that kind of hangs around the baby for about 90 days. So anyway, what else does thymosin alpha 1 do? It actually boosts natural killer cell activity. Some of you may know natural killer cells are important with testing for Lyme disease. We'll check for levels for that. It's important for cancers. In general, as your innate— general innate immune system is important to have natural killer cells, and the thymosin alpha 1 particularly And the thymus peptides actually bumps that up and helps to modulate cytokines. So do you, have you heard of cytokine storm before? Well, that was when people were getting infections, particularly the SARS-19 virus. The immune system was going crazy and it was actually attacking itself and killing themselves. Thymosin alpha 1 actually helps balance this whole thing. It's also probably one of the reasons why, and we'll get to in a second, why it actually was initially used during the COVID-19 pandemic. So what is it used for around the world? Croc, viral infections, chronic Hep C, chronic Hep B, Lyme disease, autoimmune diseases, cancer support, bunch of things used around the world. In 2020, people started, when the pandemic started, people started seeing that, hey, thymosin alpha-1 could potentially be helpful in some people because as you probably know at this stage, part of the reason why people were dying from COVID was not the virus itself, it was the cybercrime storm, your body's immune overreacting. And people started using it. The FDA, however, banned it early on in 2020 because what was happening was a lot of social media influencers or people, a lot of them weren't even medical doctors, they were non-licensed practitioners or even less than that saying, "Hey, this is amazing. It's great. Put— you can use this to treat this." And you can never say that. If something's not FDA approved, you can't say you can use you know, BPC-157 to treat, I don't know, whatever. It was not FDA approved for that. You can say it can boost your immune system. You can say it can help quell the cytokine response. You can say things like that. You can say it's been used in this country for that, you know, but you can't claim treatment. And basically, after that, FDA's response was to ban— they switched it from a Category 1 to Category 2 and banned all compounding pharmacies from making thymosin alpha-1 anymore. And it's unfortunate that a lot of people going out there, you know, trying to be the first to get clicks, the first to become famous. One of the results was the FDA said, we're not— instead of going after those people, which is near impossible to do, it's easier just to shut down the production. That's basically what happened with Amisom Alpha-1. Doesn't mean it's not useful and helpful, just means it's been made more difficult to get ahold of. And I mentioned this in a previous podcast, you know, it's— you can get a lot of these things pretty easy online. The problem is, is that they're research-grade or veterinarian-grade. Almost all these are coming at this stage from China. And it's, they're pretty easy to make. You just take some chemicals, solvents, put them together, and you can actually have these chemical reactions, make the peptides, ship them to the United States. The problem is they're filled with all these chemicals and solvents and et cetera, et cetera. And you really have to make sure that if you're sourcing it, that they're actually clearing, they're using some kind of separation process. And then it's, you get, you need, I guess, certificate of analysis showing 99.9% of whatever's in that sample is just that one thing. And most people aren't doing that due diligence. Most places aren't doing that due diligence. And one of my colleagues actually was involved with one of these companies early on, and he said the warehouse they were creating stuff in was absolutely, it was horrible. He actually stopped helping with it because of the, how bad it was. So anyway, sourcing is difficult and we'll move on to the next peptide, which is thymosin beta-4. Thymosin beta-4 sometimes is referred to TD-500. We'll talk about that in a second. They're not quite the same thing. But it's a tissue regenerator. It was discovered by Goldstein's group, the same group, George Washington University, around the same timeframe. So again, been around for about 50 years. And it's found in high concentrations in platelets. You see spikes in tissues when they're injured trying to re— repair. TB500 is actually a 17-amino acid peptide. That's a smaller segment of the entire TB4. It has a lot of the activity, but it's not the exact same thing as TB4. So you have to kind of realize that. It's a fragment. And what exactly does TB4 do? It helps regulate protein synthesis, helps regulate cell migration, helps regulate tissue repair. It stimulates new growth in injured tissues. It's used for musculoskeletal injury repairs, tendon repair and ligament wound healing. It's really interesting. It's also used in scarring issues. So in the chronic inflammatory response syndrome world, one of the cytokine markers we'll measure is TGF-beta 1. It's an indirect measurement of your Th17 cell response, which is something that calms your immune system down. So if those levels are high, you tend to see more scarring illnesses like pulmonary fibrosis, like renal fibrosis. Maybe you get injury, surgery, and you have horrible scarring, keloids. You'll see more TGF-beta activation, overactivation in those tissues, and the overactivation results in these scarring illnesses or diseases. TB4 actually calms that down. So if someone's having issues with healing and overscarring or has pulmonary fibrosis, theoretically, this could actually help calm that whole inflammatory cascade down. The point is, is that it has a lot of utility in wound healing repair. Animal data is pretty strong. There's actually a Phase 2 trial completed in 2009, but never got published. And for those of you out there know about research, you have— Yeah. Publication bias, which means only good trials get published, but there's also a publication bias where things won't get published because you can't get a journal to publish it because it doesn't go along with the narrative. You can't get enough support, editors overlook it. And so, there's a lot of negative publication biases where either bad data is not published because people don't push for it to get published, which is one type of publication bias. The other one is that editors and journals just won't pick it up because it's not— trending and, or it just doesn't fit the narrative of that particular journal. So anyway, that's thymosin beta-4. The next one actually is a super popular one, BPC-157, also known as Body Protection Compound-157. It's a pentadecapeptide, which is a fancy way of saying it's 15 amino acids. So again, amino acids make peptides. Um, it actually helps your body self-heal and self-repair. It was isolated in the 1990s. At the University of Zagreb, wherever that is, from gastric juices in humans. So it's something your stomach naturally makes to help your body heal itself. There's been over 100+ preclinical studies done. So a lot of interesting stuff on it. The other interesting thing about BPC-157 is that there are other things in your— bacteria in your gut, part of your microbiome can actually kind of replicate this as well in your body. And even certain probiotics can actually help your eyes self-heal and self-repair through activating this system. So it's really interesting peptide in that vein. The thing about BPC-157 is there— it appears to be really super safe. Personally, I use it a lot with a lot of my patients. I'll get to that in a second. So what's it do? And I'll talk about how I use it. It actually helps promote new vessels to be formed. It modulates nitric oxide, which as you— many of you all know, maybe help with vascular tone, inflammation. It helps interact with growth hormone. So if you have a growth hormone issue, sometimes just getting BPC-157 on board can actually help modulate your growth hormone, which helps with tissue healing and repair. There's a lot of great data, animal data, with healing tendons, ligaments, bone. It's really interesting. It's also neuroprotective in stroke and spinal cord injuries. I use it a lot with a lot of my autoimmune patients who develop sensitivities to everything. I've had multiple patients with Hashimoto's, who have really high antibodies who react to stuff, just putting the BPC-157 has calmed down the reaction. Anytime there's any leaky gut stuff involved, which is pretty much any autoimmune disease, or leaky brain, which is a lot of things as well, the BPC helps reform those barriers. I use it a lot in my hypermobile patients, people that have loosey-goosey tissues. It helps their tissues heal better. Um, in 2025, there was a big systematic review looking at 544 papers. You know, point is there's a lot of literature out there. There's only been one human trial in intra-articular injection for knee pain. But many of you all know it's been used across the country and we've been using it for decades. The big thing with any of these peptides, and I'll go a little rabbit trail here, is safety. You know, first and foremost, do no harm. You know, if you've— and something like that, the BPC has been used so much and it's actually safe enough that it's generally recognized as safe. It's a GRAS substance and you can get it as a supplement. Which is, this is one, and this is one of the interesting things. You can get BPC-157 as a supplement from a supplement store, but you can't get it from a compound pharmacy due to pharmaceutical regulations, right? Like, how does that quite make sense? And you are seeing some pharmaceutical-grade companies that make high-quality products taking some of the peptides and making them absorbable by mouth. They can absorb through your GI tract and then able to sell them because you kind of, as a supplement, you're able to bypass some of the FDA regulations. Many of these, however, work better with injections. They work better via IV. So you do lose some of the efficacy when you make an oral compound. But the point is, is that, you know, from the safety stuff, these things are so safe that they're allowed to make supplements out of them, but you can't make claims and you can't compound in a pharmacy. Does that— that does not make sense to you. Yeah. It doesn't make sense to me either, but that's just kind of the way, the way it is. The next combination is CJC and ipamorelin. Love this stack. It works so great. It's actually a growth hormone stack that basically activates your body's ability to make growth hormone, then blocks the breakdown. So it actually acts at two different levels. One of the cool things about CJC-1295, Ephemerone, is it also acts on growth hormone receptors that are saturatable. One of the issues with growth hormone is if you get too much of it, it can actually increase your risk for certain cancers, epithelial cell cancers or prostate, ovarian, lung, breast. Well, if you— so, which was the concern with growth hormone when you get to be over 50, getting too much of it, which you can do with some of the more potent growth hormone things. It doesn't happen with this one. If you take like, say, 20 units versus 5 units, once you hit the threshold, which is usually about 7 or 8 units in the product I'm referencing, the more doesn't work anymore. It also doesn't hurt you. So that's one of the cool things about this particular peptide. I don't want to say it's not overdoseable, but it's kind of sort of hard to do that. So background on CJC-ipamorelin. Your growth hormone doesn't flow all the time and actually pulses throughout the day. And so one of the issues with us as we get older is we pulsate it less. You also get a dysfunction in your HPA axis, your hypothalamic-pituitary-adrenal axis, or hypothalamic-pituitary growth hormone, et cetera, axis. And after 30, the pulsation declines a lot. So what happens is we older, we just older, get older, we just don't heal quite as well. So if you notice, like when you're— I'm 53 right now and I was having some shoulder issues for almost a year and used some of this stuff and things heal up in 4 to 6 weeks. As you get older, you just don't heal quite as well from anything and your growth hormone levels come down. So this is, this is something that can actually help your body's natural healing capabilities. The CJC is a synthetic analog to GHRH. And sometimes you'll have a DAC, D-A-C, which I do not use this at all. And this is where it gets a little tricky because sometimes you'll see CJC/DAC, that's a half-life of 7 days. That's where you can get into some problems where you take something that should be a pulsatile in and out in a couple hours, right? That one particularly will last for again for 7 days. And that's where you can actually, the whole thing I mentioned about the receptors being saturatable, you kind of override that. And that's where you can get into some problems. So again, even with things that are out there, knowing the nuances can get kind of tricky. Yeah. And with the DAC, you can have your growth hormone levels up to 1,000 times elevated for 6 days. You know, is that, Is that ideal? Probably not. You want to get, you know, an elevation, maybe 100 to 200% over 4 to 6 hours and then normalize. You don't want a, you know, 1,000% elevation for 6 days, which is what the DAC molecule can do. Omnipramirilin works differently. It's actually a ghrelin— mimics ghrelin, which is one of the satiety hormones. If you've heard about the different— there's different satiety hormones that are made in your brain. That can actually either stimulate hunger or satisfaction, stimulate insulin to store energy or your body to use it. Ghrelin's one of those things that helps you actually, you want to be higher to help utilize energy production. So the different ghrelin actually acts through that pathway. Short half-life, 2 hours. And also the ghrelin also helps with fat mobilization. So if you're gaining weight, one of the things that happens as you get older with the growth hormone, you get like the— For guys, you get the little belly right here. And you might have everything up top might be down, down, down, but you store things in the middle. That can be a marker for just decreased growth hormone levels as you get older. And so that's where this kind of stacked together can work really nice. The problem with it is that, again, it's one of the peptides that's been kind of mixed due to some of the FDA kind of stuff. It's been used for bodybuilders, sleep quality. Oh yeah. One of the interesting things I didn't mention is sleep. Sometimes sleep disturbances occur because of your growth hormones going down as you get older. You sleep less. You get less hours of sleep and less depth of sleep. Using something like this can actually help with that. If you're only using it once a day, it actually works best to do before you go to bed on a fasting stomach at night. It can actually improve sleep quality. And it's been, yeah, for that reason it's been used for, as an anti-aging peptide, speeding recovery. There is a risk. Yeah, I mentioned this before. Theoretic risk for hormones. Sorry, for growth hormones increasing risk for cancer, which is the reason why I prefer the CJC-ipamerillin without the DAC and without— and some of the other— not some of the other ones that are more potent because there's— because they're stronger for longer. That's where you get into the concern with the cancer risk. And we can stop here at GHK-Cu. It's actually an interesting peptide that was discovered again, discovered in the '70s. It's a tripeptide. So it's 3 amino acids with a copper. So typically when you see it, you'll see GHK, which is, you know, the 3 amino acids, dash CU. Used in a lot of facial products. It's actually helps with skin regeneration. I'll actually compound it sometimes in this facial. You can, this is one you can still compound topically. It's actually helped with skin regeneration. It's naturally produced in your body. And the levels, as with many of these peptides, your body makes a lot when you're young, you make less when you get older. Um, and it was not banned, which I may not mention. It was not banned in 2023. It's still considered Category 1. It stimulates collagen as well as these things called GAGs or glycosaminoglycans to regenerate. So it can be helpful with wound healing repair, tissue healing repair, typically used topically for a lot of things for hair regrowth as well as for just making your skin look better. It promotes nerve growth and some early-stage research says it may reset gene expression in tumor cells towards more normal patterns. So it's a really interesting kind of peptide still available. But it's really underrated. A lot of people don't see how useful this one can be used because it's not used a lot with muscle building and not used a lot in the anti-aging world. You won't hear about as much on certain social media, but it is being used a lot in the aesthetic plastic surgery skin world. So you might hear it. It's one of those interesting Goldilocks peptides where you might hear about in one world, but not the other. So what's the point? And then to keep things in mind, and we'll stop, this will be the last peptide thing. There are over 7,000 peptides that we know of currently and maybe 30+ that we've been able to— I'm sorry, but it's about 70+ we've been able to actually synthesize. Many of them are like these. They have, they all, they cross-react with each other. They're helpful with your body's natural healing repair. The way I think about them is do the foundational work first, nutritional work, replace deficiencies, remove chemicals, toxins. And if you're still not healing, your body's still not healing, repairing quite adequately, and you're, you know, over 40, then the peptides can be super helpful. But some of your other patients ask me about peptides in like in their late teens, early 20s. I just really try to avoid them at that age group. If you're having problems healing and you're at 19 or 20, you need to figure out why. You need to figure out what your deficiency is, the toxin exposure is, what your sleep problem is, your dietary issues. Are you not getting adequate protein, the type of quality of protein? Just bypassing all that and going right to peptide in your 19, 20, 21 is a sure way to like not being great in your 30s or 40s. So I've had some patients, younger patients ask me for that stuff and it's just, it's something tricky. So hopefully this information was helpful. Again, if this has been helpful, please follow us. Most people who are listening to this right now aren't actually following us. It just helps us with metrics and also helps us to get this information out there better. Take care. We'll talk to you soon. Bye.
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