Peptides - Here’s what you need to know

I’ve seen A LOT of discussion on peptides recently. This is a broad topic with lots of different classes of peptides. There are lots of nuances involved in this new modality but I'll share a few thoughts.

I want to preface this by saying that we DO peptide therapy at the office. However, we we do it proper care, follow up and caution. We go case by case and determine if you need it or not.

There are a lot of people talking about the benefits of peptides and these molecules are being hailed as a fountain of youth. While I do appreciate the unique benefits that peptides can have, I’m also concerned about side effects that I do not see being discussed and long term issues that we do not fully understand at this point.

Peptides are synthetic signaling molecules -- most require injection because your gut destroys them (however, we use liposomal, sublingual peptides that bypass the gut and do not require injection).
For people trapped in severe obesity or metabolic dysfunction, GLP-1s can be a genuine lifeline -- breaking a cycle that diet alone couldn’t crack and reducing cardiovascular risk.
The science of incretin signaling, driven by GLP-1s, has taught us more about satiety than anything in the last 50 years
Some peptides like BPC-157 show real promise for acute injury recovery in animal models -- but the human evidence is almost nonexistent
The trade-offs are real: up to 40% of weight lost on GLP-1s may be muscle, stopping means rapid regain, and the drug class is escalating -- from single to dual to triple receptor agonists -- each more potent, each less understood long-term
BPC-157 and TB-500 ("the Wolverine stack") promote blood vessel growth through the same pathway active in half of all human cancers. Almost zero human data
Growth hormone secretagogues can worsen insulin resistance and elevate cancer-linked IGF-1
Melanotan crosses the blood-brain barrier and has been linked to melanoma in case reports
The biggest concern: these drugs treat the symptom without addressing the root cause -- and none of them replace what food, sunlight, sleep, and movement can do.

Peptides are short chains of amino acids -- small proteins, essentially. Your body already produces hundreds of them naturally. Insulin is a peptide. Growth hormone is a peptide. These are signaling molecules -- they bind to specific receptors and tell your cells what to do.

Synthetic peptides are lab-engineered versions of these natural signals, modified to be more potent and resist degradation. Most have to be injected, because your gut would break them down before they ever reached your bloodstream.

So when people talk about "taking peptides" -- what they actually mean is self-injecting synthetic versions of molecules your body already makes. The question is whether overriding your body’s natural signaling with exogenous versions is as consequence-free as the internet would have you believe.

Look, I get the appeal. They sound like something from a Marvel superhero movie.

Faster healing. More muscle. Less fat. Anti-aging. Better performance. Longer life.

The question I’ve been asking is… at what cost?

Here's what the supply chain actually looks like:

- U.S. peptide imports from China roughly doubled in a single year -- $328 million -- and that's just what's being tracked.

- The FDA tested products from online peptide sellers and found up to 40% contained incorrect dosages or undeclared ingredients.

- Purity rates as low as 7%. That means you could be injecting 93% of something else (PMID: 39509151).

- Seven of the biggest peptide vendors shut down in 2025 alone. Peptide Sciences -- one of the largest suppliers in the country -- closed just last month.

This is the supply chain people are trusting with their health. Unregulated labs, unlabeled compounds, and vendors disappearing overnight.

#1 Recovery peptides -- BPC-157 & TB-500

BPC-157 is the one people call the "Wolverine peptide." The claims: heals tendons, fixes gut issues, repairs the brain.

It’s derived from a protective protein found naturally in gastric juice -- your gut already produces a version of this.

Almost all the evidence comes from rat studies -- and the majority from a single lab group in Croatia. As of today, there are no published randomized controlled trials in humans. The largest human study? Two people, receiving IV BPC-157 in a pilot safety test. That’s it. Two people.

Here’s the mechanism that concerns me most…

BPC-157 promotes angiogenesis -- the formation of new blood vessels -- by enhancing a signaling pathway called VEGFR2.

In a healing tendon, new blood vessels are exactly what you want. But VEGFR2 isn’t selective. That same pathway is active in roughly half of all human cancers -- it’s how tumors build their own blood supply to grow and metastasize. If you’re injecting a compound that promotes blood vessel growth systemically, and you happen to harbor an undetected malignancy -- which is more common than most people realize -- you could be vascularizing a tumor you don’t even know exists.

No study has been designed or powered to detect this risk. Absence of evidence is not evidence of absence.

People are also combining BPC-157 with TB-500 to create their "Wolverine stack."

TB-500 is closely related to thymosin beta-4, which has been found to accelerate dormant tumor growth and disrupt immune response in animal experiments. Same angiogenesis concerns. Same absence of human safety data.

But here’s what concerns me: the majority of people I see on these drugs have no exit strategy. They’re losing weight without building the habits, the understanding, or the metabolic foundation that would let them keep it off without the drug. And the science is clear -- when you stop, the weight comes back faster than if you’d never started.

So if you’re using a GLP-1, use it as a bridge, not a destination. Pair it with real food. Build muscle. Fix your sleep. Understand why your satiety broke in the first place. The drug can buy you time -- but only you can do the actual work.

I believe it's only a matter of time before we see the same pattern of trade-offs playing out with the other peptides.

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