The word peptides has gone vertical — Dr Alex Tatem notes searches have jumped around 400% in a short window — and most of what’s written about them online is either breathless hype or a product page in a lab coat. So when a practising urologist sat down on The Diary of a CEO to explain what peptides actually do, in front of 2.6 million viewers, it was worth watching properly. We did — all 90 minutes — and this is the detailed, honest breakdown: the science, the colourful demo of vials on the table, the patent-and-pharmacy backstory behind the bans, the 2026 FDA reversal, and the one thing every UK buyer should take away. Plus the part the video never mentions: what any of it means in Britain.
This article references and summarises that interview throughout. You can watch the full Diary of a CEO episode with Dr Alex Tatem here.
Key takeaways
- Peptides are targeted “keys”, not blunt instruments — short amino-acid chains built to hit one specific receptor, versus a small-molecule drug’s “hammer”.
- BPC-157 and TB-500 were the repair-and-recovery headliners; GHK-Cu for skin, MOTS-C as “exercise in a vial”, plus sleep, cognition and GLP-1 metabolic peptides.
- The 2023 US ban wasn’t really about safety — Dr Tatem traces it to a 2013 patent ruling and a 2012 pharmacy scandal, and frames the resistance as “machines designed to prioritise profit”.
- In 2026 the FDA signalled a reversal — considering returning seven peptides (including BPC-157 and TB-500) to legal compounding.
- His sharpest warning was about quality: unregulated “research-only” peptides are like “gas station sushi” — no standardisation — which is exactly why a batch COA matters.
- UK context (not in the video): the FDA is a US regulator. In the UK these remain research-use-only research chemicals with no MHRA authorisation.
Who is Dr Alex Tatem?
Dr Alex Tatem is an internationally recognised urologist who, by his own account, has studied peptides for around 12 years and runs a men’s health clinic, alongside a YouTube channel demystifying the field. That background is what makes the interview useful: it’s a clinician describing what he has actually prescribed and observed — and, refreshingly, where the evidence runs out. He repeatedly draws a line between “what I can prove versus what I suspect”, which is more than most of the internet manages.
What is a peptide? Dr Tatem’s four explanations
The clearest part of the whole episode is how he demystifies the basic idea. A peptide, he says, is “a structural class of medications” built from amino acids — “the Legos that make up proteins” — assembled into fragments designed to target one specific receptor.
Four images he used, all worth borrowing:
- The key and the lock. Where a conventional small-molecule drug is broad-acting, a peptide is “a very specific targeted key to unlock a very specific lock.”
- The hammer. Small molecules are like a hammer — great for a nail, but try to use it on a screw or a flat-pack table and “it may not always end the way that you want to.” That collateral damage, he notes, is why many small molecules fail FDA approval on safety.
- The Lego set. The same bricks build a rocket, a pirate ship, a race car — which is why one compound class can touch skin, sleep, healing and metabolism.
- The app on your phone. His summary line: “the question isn’t what can peptides do, it’s what can’t they do” — and if they can’t do something yet, one can probably be developed for it.
He also grounds it in history: the first peptide used in medicine was insulin in 1921; in his own field of urology, Lupron arrived in 1985 to shut down testosterone production in prostate-cancer patients. Peptides aren’t a 2020s fad — the toolbox is a century deep.
The peptides on the table: a guided tour
Much of the episode is Dr Tatem picking up vials and explaining them. It’s the most quotable stretch — and a useful map of the category:
- GHK-Cu — “probably the most well-known peptide for skin complexion,” which also “improves quality of hair and nails.”
- Epitalon — sometimes sold as a longevity miracle; he’s honest: “maybe maybe not going to be the fountain of youth, but I’m very skeptical.”
- A sleep peptide — injected at night, “it would improve your quality of your sleep.”
- Melanotan II — produces a deep tan from minimal UV, and, he warns with a grin, “some of the most impressive erections you’ve ever had in your life, so be warned.”
- Methylene blue — the one he actively cautions against: “Don’t take this. It literally will stain your nails blue and your hair blue.”
- BPC-157 and TB-500 — the repair-and-recovery pair, plus muscle-building compounds.
His through-line: these are powerful, specific tools — but “there are trade-offs,” which is why he doesn’t simply take all of them himself.
BPC-157: the repair headliner
Dr Tatem calls BPC-157 “probably one of the most popular peptides” in the conversation today. He describes it as “a synthetic version of a naturally found peptide in the gut” that “enhances blood vessel growth in areas of injury” — logical, he notes, given the gut’s job of constantly repairing its own acid-exposed lining.
His headline evidence is the animal work: researchers have “completely transected the Achilles tendon in rats” — surgically cut, not merely strained — and seen spontaneous healing with BPC-157. He keeps the caveat firmly attached, with the episode’s best line: “If you have an Achilles tendon injury and you’re a rat, BPC-157 is one of the best things that you can ever have.” It is, he stresses, “not a one-to-one translation” to humans, and “we need more data.”
On safety, he makes a genuinely striking point: in toxicology you look for the LD50 (the dose at which half a population doesn’t survive) and the LD1 (enough to harm even 1%). For BPC-157, “we have yet to figure out what the LD1 dose is… because it is so incredibly well tolerated.” At MyReta, BPC-157 is the backbone of two research blends: the Wolverine Stack (BPC-157 + TB-500) and the triple-peptide Klikglow (BPC-157 + TB-500 + GHK-Cu).
TB-500: “the brother to that”
He introduces TB-500 as BPC-157’s sibling, describing it as improving blood flow to an injured area: “you could think of this as sending the soldiers, as sending the cells that are required for rebuilding that tissue matrix that was damaged by a tear or a cut.” The two are routinely studied together — the entire logic of the Wolverine Stack. For how they combine with GHK-Cu, see our deep-dive Klikglow 70mg analysis.
MOTS-C: “exercise in a vial”
One of the more striking descriptions in the episode: MOTS-C, which “some people just will call exercise in a vial.” In his words it “improves your VO2 max and your exercise tolerance” by upregulating the energy pathway and “making more ATP… available.” We stock it as KIIKMOTS-C 10mg.
The GLP-1 revolution — and the unreleased “trillion-dollar” peptide
Dr Tatem is openly bullish on GLP-1 peptides for metabolic health. He opened the entire episode describing an as-yet-unreleased compound that “actually tortures belly fat at a disproportionate rate,” delivers “the best improvements we’ve ever seen in… liver health,” and which he predicts “is going to be a trillion-dollar drug when it comes out.”
He didn’t name that one on camera — but a pre-launch, multi-action compound with dramatic visceral-fat and liver effects fits the next-generation triple-agonist class that retatrutide belongs to. That’s our core focus: see our retatrutide UK page and products such as Retaklik (Retatrutide) 60mg and Retatrutide 2.0 (45mg).
The success story he leads with
Asked for the most incredible impact he’s seen, Dr Tatem describes treating young, morbidly obese men with infertility — low sperm counts driven by insulin resistance and a damaged endocrine system. Weight loss is the real fix, but, as he puts it, “losing weight is really, really hard.” Then GLP-1s changed the maths: he describes a patient who “increased his sperm count 10 times over… because he’s lost 100lb due to using tirzepatide, exercising, and improving his diet. And that started with a peptide.” It’s the cleanest illustration of his point that these compounds treat causes, not just symptoms.
Why were they banned? The patent-and-pharmacy backstory
This is the most genuinely original part of the interview — the history almost nobody else explains. Dr Tatem ties the bans to two events:
- The 2013 Myriad Genetics ruling. The company had patented the BRCA1 and BRCA2 genes; the US Supreme Court ruled you can’t patent something natural found within the body. A win for patients — but, he argues, with an “unintentional byproduct”: pharma lost any incentive to develop promising natural compounds it couldn’t monetise.
- The 2012 compounding-pharmacy scandal. A New England compounding pharmacy shipped contaminated product that caused a fungal meningitis outbreak. The FDA stepped in with new federal oversight, eventually sorting compoundable ingredients into categories.
From roughly 2014, these peptides sat in “category one” — legally compoundable, and Dr Tatem prescribed them. Then in 2023, the FDA reclassified 19 popular peptides to “category two” — banned overnight. As he describes it, clinicians simply received an email from their compounding partners: “we can’t make this anymore. We’re sorry.”
What a compounding pharmacy actually is
For context he rewinds further: back in the 1800s and early 1900s, your pharmacist “would actually make your medication in front of you… custom for every single patient.” Mass-production standardised everything into one-size-fits-all doses — which, he points out, is faintly absurd: why is the adult dose of a blood-pressure pill identical regardless of body size? Compounding pharmacies (now sophisticated 503A operations) still make custom formulations — and that flexibility is central to the current fight.
MK-677 and the growth-hormone peptides
He gives a vivid example of what was lost. MK-677 (ibutamoren) — technically a small molecule swept up in the same ban — is orally available, binds the ghrelin receptor and triggers significant growth-hormone release plus hunger. For cachexia patients (cancer treatment, severe malnutrition) who couldn’t eat enough, “patients were actually able to eat more to meet caloric goals.” Alongside it, GHRP-2 and GHRP-6 (growth-hormone-releasing peptides) and thymosin beta-4 derivatives were in routine use — “and they were working… and we were not seeing adverse events, which is the most important thing.”
The “profit machine” framing
On why they were banned, Dr Tatem is careful but pointed. Officially: “insufficient data” for safety, because the compounds never completed full FDA approval. Unofficially, he notes the obvious commercial logic — a patient’s “$10, $15” spent on a cheap, unpatentable peptide “doesn’t go to a prescription drug from a commercial pharmaceutical company.” His most memorable framing rejects cartoon villainy for something more structural: the “Illuminati” isn’t hooded figures, it’s “large machines that are designed to prioritise profit over everything.” He also references that the current US administration, via RFK Jr, has called the 2023 move “illegal.”
The 2026 FDA reversal
The timely news: per Dr Tatem, the FDA issued a press release stating that in July it would consider returning seven peptides from category two to category one. The heavy hitters he names: BPC-157 and TB-500, plus KPV (linked to angiogenesis and tissue repair), MOTS-C, and DSIP, epitalon and C-max (sleep, recovery and cognition). He also flags that the same pharmaceutical companies resisting cheap peptides have themselves signed “multi-billion dollar deals… aided by AI to try and fast-track their own peptide products” — so the pipeline is coming either way.
The tirzepatide flashpoint
The most charged section is about GLP-1s and compounding. He contrasts a branded Mounjaro auto-injector pen with a compounded vial of tirzepatide combined with niacinamide — the latter not an exact patent copy, allowing flexible “microdosing” through the week instead of one large weekly dose that leaves some patients ill. His claim about the crackdown is striking: FDA commissioner Marty Makary “has now tweeted more about cracking down on compounded GLP-1 medications than he’s tweeted about diabetes or heart disease in his entire time in office,” with lobbying pressure from Lilly and Novo Nordisk. His preferred outcome isn’t one product winning — it’s “an ecosystem where you have choice so you can make the right choice for the right patient.”
How peptides are actually taken (what he explained)
For background — not as instruction — Dr Tatem explains why most peptides are injected rather than swallowed: your gut treats an oral peptide like any protein and breaks it into pieces, so “your body wouldn’t be able to tell the difference between that and a piece of chicken.” There are exceptions (a gut-tolerant form of BPC-157), but the majority are administered subcutaneously or intramuscularly. He notes the practical trade-off: branded auto-injector pens are simple but fixed-dose, while research-market vials require you to draw up and calculate doses yourself — flexible, but only if you know the maths.
What does Dr Tatem take himself?
Asked directly, he’s candid: the only peptide he’s currently taking is “a small dose of tirzepatide.” A powerlifter who could deadlift 500lb but found three flights of stairs a chore, he chose to slim down for longevity. Why not the others? “Honestly, because right now there is not a legal framework for me to obtain them” — and, as a clinician, “I want to be an example for my patients.” It’s a notably disciplined answer from someone enthusiastic about the whole category.
But what does this mean in the UK?
Here’s the context the video doesn’t give, because it’s an American conversation. The FDA is a US regulator. Its category decisions govern US compounding pharmacies — they do not legalise anything in Britain.
In the UK, peptides like BPC-157, TB-500, GHK-Cu and MOTS-C have no MHRA marketing authorisation. They are not approved medicines here, and are supplied strictly as research chemicals for laboratory use only — not for human consumption. A US move toward re-legalising compounding is an encouraging signal for the research direction, but it doesn’t change the UK position today.
His most important warning: the “gas station sushi” problem
The single most useful thing he said for UK buyers wasn’t about any one peptide — it was about quality. Describing the unregulated grey market that filled the vacuum after the 2023 ban (he likens the ban itself to Prohibition — drive it underground and the contaminated supply follows), he warns that buying from it is “kind of like getting gas station sushi… you don’t really know if it’s sushi and it may not end very well for you,” precisely “because there isn’t any quality control.”
That is the whole game. The risk in this category isn’t the molecule — it’s not knowing whether the vial contains what the label claims. The answer to gas-station-sushi is a batch-specific, third-party Certificate of Analysis: the standardisation Dr Tatem says the grey market lacks. It’s the exact standard we hold ourselves to — see our Certificate of Analysis process and quality testing pages. If you take one thing from the whole 90 minutes, take that.
Quick reference: the peptides he covered
| Peptide | Dr Tatem’s description | FDA 2026 review? | At MyReta |
|---|---|---|---|
| BPC-157 | Gut-derived; enhances blood-vessel growth in injured tissue; “incredibly well tolerated” | Yes — named for return | Wolverine Stack, Klikglow |
| TB-500 | “The brother”; improves blood flow, “sends the soldiers” for repair | Yes — named for return | Wolverine Stack, Klikglow |
| GHK-Cu | Best-known peptide for skin complexion, hair and nails | Not on the seven | Klikglow |
| MOTS-C | “Exercise in a vial”; VO2 max, exercise tolerance, more ATP | Yes — named for return | KIIKMOTS-C 10mg |
| GLP-1 class (tirzepatide) | Metabolic transformation; the infertility / 100lb case | Separate compounding fight | Retatrutide range |
| KPV / DSIP / epitalon / C-max | Tissue repair, sleep, recovery and cognition | Yes — named for return | — |
Frequently asked questions
What did Dr Alex Tatem say peptides actually do?
He describes peptides as targeted amino-acid “keys” that act on specific receptors, spanning healing and tissue repair (BPC-157, TB-500), skin (GHK-Cu), exercise capacity (MOTS-C), sleep, cognition and metabolic weight loss (GLP-1s like tirzepatide).
Why did the FDA ban peptides in 2023?
Officially, “insufficient data” on safety because they hadn’t completed full FDA approval. Dr Tatem links the backdrop to a 2013 patent ruling and a 2012 compounding scandal, and notes commercial incentives at play — with RFK Jr calling the move “illegal”.
Which peptides is the FDA reconsidering in 2026?
Per Dr Tatem, seven: BPC-157, TB-500, KPV, MOTS-C, DSIP, epitalon and C-max.
Are peptides legal in the UK?
Compounds like BPC-157, TB-500, GHK-Cu and MOTS-C have no MHRA authorisation in the UK and are supplied strictly as research chemicals for laboratory use only, not for human consumption. The FDA’s US decisions don’t change UK law.
Is BPC-157 safe?
Dr Tatem highlights that it appears very well tolerated — researchers haven’t established a dose that harms even 1% of subjects — but stresses the strong evidence is still preclinical (animal models) and more human data is needed.
How do I avoid fake or low-quality peptides?
His “gas station sushi” warning is the answer: the unregulated market has no standardisation. Insist on a batch-specific, third-party Certificate of Analysis confirming identity and ≥99% purity before buying.
The bottom line
Dr Tatem’s interview is one of the clearest mainstream explanations of what peptides do — precise about the science, candid about the politics, and blunt about the quality risks. For UK research buyers, two things carry over: his framing of peptides as targeted tools, and his warning that without quality control you’re gambling. We built our range around that second point — lab-tested, COA-backed research peptides. Browse current stock in our shop, and watch the full Diary of a CEO episode here.
This article summarises and comments on a third-party interview for informational purposes and is not medical advice. All MyReta products are supplied for laboratory research use only and are not for human consumption.