The evidence register
Start with the goal. Follow the evidence.
Peptideworth grades every compound it tracks by how far the published human evidence actually goes — and says plainly when that is nowhere.
Of the 13 compounds in this register, 6 have randomized human trials behind them, 5 have early human data only, and 2 have never been published in a person at all. 7 of the best evidenced cannot legally be bought.
Last checked August 2026
- Compounds graded
- 13
- Papers read
- 79
- Companies audited
- 96
- Research articles
- 35
Four steps, weakest to strongest
We show the step the published evidence reaches — not the step the seller implies.
- Anecdotal0
User reports and forum consensus. No controlled data.
- Animal only2
Rodent or cell studies. Nothing published in humans.
- Early human5
Small, open-label, or phase 1/2 trials. Promising, unproven.
- Randomized trials6
Randomized controlled trials in humans, at scale.
Start here
What are you trying to fix?
6 goals, each ranking its compounds by how far the published human evidence actually goes. The grade beside each one is the strongest step any compound on that page reaches — not an average, and not a promise.
Weight loss
Four peptides have real weight-loss trials behind them. The rest have animal data or nothing. Here is what each one did, and what happens when you stop.
Randomized trials
4 of 8 at this tier · 9 papers
Weight-loss plateau
The weight curve flattening is a trial finding, not a failure. What STEP 5, SURMOUNT-4, STEP UP and SURMOUNT-5 measured about what happens next.
Randomized trials
3 of 5 at this tier · 11 papers
Muscle loss on a GLP-1
About a quarter of the weight lost on an incretin drug is lean mass. Here is what the trials measured, and which compounds have evidence for holding onto it.
Randomized trials
3 of 6 at this tier · 9 papers
Visceral fat
One peptide is FDA-approved specifically to reduce visceral fat — in one narrow population. Here is what it did, and what the GLP-1 drugs did alongside it.
Randomized trials
3 of 6 at this tier · 8 papers
Injury recovery
BPC-157, TB-500, GHK-Cu: the animal data is genuinely good and the human data barely exists. What is registered, what has reported, and what has not.
Early human
1 of 5 at this tier · 7 papers
Sleep
One peptide has a randomized sleep-outcome trial behind it, and it is not one of the peptides sold for sleep. What the trials measured, and what they did not.
Randomized trials
1 of 5 at this tier · 5 papers
The evidence and the availability do not line up.
Two lists fall straight out of the register, and they point in opposite directions. Neither is a recommendation — one is a supply fact, the other is an evidence fact.
Well evidenced, not available
7- SermorelinCompounding restricted
- SurvodutideResearch use only
- CagrilintideResearch use only
- GHK-CuCompounding restricted
- GlutathioneCompounding restricted
- NAD+Compounding restricted
- RetatrutideResearch use only
Real trial data, no legal route to buy them for use in a person. If a seller offers you one of these, that is the fact worth knowing first.
The registry
Every compound we have reviewed
One page per molecule, whatever its evidence tier — including the ones where the honest answer is animal data only.
Ordered by how far the published human evidence goes, strongest first — then alphabetically. Nothing else moves a row.
| Compound | Strongest evidence | Availability | Papers |
|---|---|---|---|
| Bremelanotide (PT-141) | Randomized trials | FDA-approved | 7 |
| Semaglutide | Randomized trials | FDA-approved | 7 |
| Sermorelin | Randomized trials | Compounding restricted | 5 |
| Survodutide | Randomized trials | Research use only | 6 |
| Tesamorelin | Randomized trials | FDA-approved | 9 |
| Tirzepatide | Randomized trials | FDA-approved | 9 |
| Cagrilintide | Early human | Research use only | 6 |
| GHK-Cu | Early human | Compounding restricted | 5 |
| Glutathione | Early human | Compounding restricted | 5 |
| NAD+ | Early human | Compounding restricted | 4 |
| Retatrutide | Early human | Research use only | 8 |
| BPC-157 | Animal only | Compounding restricted | 3 |
| TB-500 | Animal only | Research use only | 5 |
The companies
108 of 374 product claims match the trial behind them.
We read what 96 companies say about every peptide they sell and check it against the published record. A claim that outruns its evidence is the single most common thing on a peptide storefront.
- Publishes a testing regime16
- Names the pharmacy that fills it41
- Publishes a readable certificate of analysis0
The research
What the evidence actually shows
- Compound Classes
- 13
- Sourcing & Compounding
- 4
- Dosing & Effects
- 8
- Reading the Evidence
- 10
Amylin Analogs: The Next Class After Incretins
An amylin analog has been FDA-approved since 2005. What changed is not the hormone — it is how long the molecule lasts. The trials, in order.
ReadBPC-157 Side Effects: What the Human Record Actually Shows
Three small human reports, 30 people, no control groups and no side effects recorded. Why that is not the same as safe, and what FDA said about BPC-157.
ReadCertificates of Analysis: What They Prove
A COA is a claim about a lot, not a guarantee about a vial. What each test answers, what a purity figure cannot say, and the gap the document never closes.
ReadCJC-1295 and Ipamorelin: The Record Behind Each Half
CJC-1295 and ipamorelin were each tested in small human studies. The pair has never been tested together, and neither has a lawful compounding route.
ReadCompounded Is Not the Trial Drug
A trial tests one defined article: a molecule, a form, a concentration, a container. Compounding changes some of those, and the evidence travels that far.
Read503A vs 503B: What Is Actually in the Vial
One scheme is inspected against manufacturing standards; the other is not. What each may legally start from, and what the inspection record shows in practice.
ReadTools
Calculators, not dosing advice
Each one converts numbers you already have — a vial's printed strength, how much water you mixed in, a dose you and a clinician have already chosen — into syringe units. None of them suggest a dose, a starting point, or a schedule.
- Reconstitution calculatorConvert a peptide vial's strength and your bacteriostatic water volume into insulin-syringe units for a dose you supply. Arithmetic only — not dosing advice.
- Retatrutide calculatorConvert a retatrutide vial and your bacteriostatic water into syringe units for a dose you set. Read the supply and approval facts first — they matter more.
- Microdosing split calculatorDivide a weekly total you have already decided on into smaller injections and see the syringe units for each. Your numbers only — no chart of amounts to copy.
- Unit converterConvert one quantity between micrograms, milligrams, milliliters and U-100 syringe units at a concentration you supply. Arithmetic only — never dosing advice.
- Bacteriostatic water calculatorWork out how much bacteriostatic water to add to reach a concentration you have chosen, and what one syringe unit is worth once you get there.
How we grade
Grant Delaney
Research Editor
- Graded, not asserted
- Every compound carries the evidence tier its published trials support — and keeps it when that tier is inconvenient.
- Numbers from the paper
- Every figure is quoted from the trial it cites, with the PMID to check it. No figure on this site was written from memory.
- Weak evidence stays weak
- We say when the answer is animal data, or nothing. On this register that is 2 of 13 compounds, and we do not round it up.
Read how we research and rank in our editorial policy, and how we stay independent on our about page.