How we grade
Peptide Reader does not grade how promising something is. It grades how much is known about it, and who it has actually been tested on. Those two things get mixed up constantly in the way peptides are sold, and that confusion is the entire reason this register exists.
There are five levels. Something moves up a level only when published evidence justifies it — never because it is popular, and never because the explanation of how it works sounds convincing. A convincing explanation is a hypothesis, not a result.
The five levels
Strongest first
- T5
Approved medicine
Approved by the European or US medicines regulator for a named condition, after large randomised trials, with a public product information sheet anyone can read.
For example: Semaglutide, insulin, teriparatide
- T4
Still being tested in people
Currently in registered clinical trials in humans, but not approved anywhere yet. The trials may still fail — most drugs at this stage do.
For example: Retatrutide
- T3
Tested in people, but barely
Human studies exist, but they are small, short, uncontrolled, paid for by the seller, or they measure something easy to measure instead of something that matters.
For example: Several skincare peptides
- T2
Only tested on animals
The evidence is animal experiments, cells in a dish, or computer models. No meaningful controlled trial in humans has been published.
For example: MOTS-c, TB-500
- T1
No real evidence at all
Nothing published worth citing, in any species. What circulates is anecdote, sales material, or a guess extrapolated from something else.
For example: Several compounds sold as research chemicals
The rules we follow
Which sources count
We cite original sources wherever we can: published studies with a DOI, the official product information from the European and US regulators, decisions from the Swedish Medical Products Agency, the text of the law itself, and the World Anti-Doping Agency's prohibited list. We use summaries and review articles only when they are summarising that kind of material.
We never cite a shop, a forum, a podcast, or an article that has no source of its own. If a claim can only be traced back to someone who makes money from the compound, we do not publish the claim.
How we check the chain
Every amino acid sequence is looked up in the public chemical and protein databases and compared letter by letter. If we cannot confirm it there, we print no sequence at all — the field says so plainly instead.
Leaving the gap visible is deliberate. A wrong sequence is worse than an empty box, because it looks exactly as trustworthy as a correct one.
How each entry gets checked
Every entry is written by one person and then checked by a second, whose job is to try to knock it down: re-check the chain against the original source, open every link, argue with the evidence level, and rewrite any sentence that reads like an advert.
When there is doubt, the level always goes down, never up. An open-label study in twelve people is limited human data, not a late-stage trial.
What we deliberately leave out
No doses. No instructions for taking anything. No suppliers, shops or price comparisons. That applies to approved medicines too — that conversation belongs with a doctor, not on a web page.
Advertising an unapproved medicine to the public is also illegal in Sweden under the Medicinal Products Act (2015:315). Describing what the evidence shows is not advertising. Describing how to use these compounds would be.
How we write about what we don't know
Where the evidence is missing, we say it is missing, as plainly as we would report a positive result. We only write "studies suggest" when there are studies, and then we name them.
The register has no opinion about whether something is good. It only has a view on how much is actually known.
Mistakes and updates
We review entries again when new evidence is published, when an approval changes, or when the doping list is updated. The date at the top of the page is when we last went through it, not when we last edited a word.
If you find a mistake, we want to know. Send the source along with the claim you think is wrong, and we will correct it and note the change.
Peptide Reader does not tell you what to do. It tells you what is known, and how well.
Peptide Reader is a reference work, not medical advice. Where an amount appears it is what a named study gave its participants, reported as a fact about that study. The site carries no instructions for use and no places to buy. Always talk to a doctor about treatment.
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