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Methodology

How we grade

Every peptide gets one grade. It answers a single honest question. How much do we actually know about this in humans?

The grade is not “does it work”, because that is usually unknown. It is not “is it popular” either. It measures how solid the human evidence is underneath the claims. A peptide can be fascinating in the lab and still score a D. Exciting animal data is not proof in people.

The scale

A

Grade A · Approved / strong human evidence

Approved medicine or robust human trials.

B

Grade B · Promising human evidence

Human trials exist but are incomplete.

C

Grade C · Early / limited human data

Some human data, far from settled.

D

Grade D · Animal data only

No meaningful human evidence yet.

F

Grade F · Negligible evidence / harm

Little to no human data, or documented harm.

Where the evidence comes from

We weight sources roughly in this order, and we say when something rests only on the weaker ones.

  1. 01Human randomised controlled trials and regulatory approvals. The gold standard.
  2. 02Other human studies. Cohort, observational and small pilot work.
  3. 03Systematic reviews and meta-analyses. Of the studies above.
  4. 04Animal and in-vitro studies. Useful signals, but not proof in people.
  5. 05Case reports. The lowest weight, and flagged as such.

Primary references come from PubMed and the clinical-trial registries (ClinicalTrials.gov and the ISRCTN and EU registries). Every entry links its sources so you can check our work.

What we will never do

  • Give doses, protocols or “how to use” instructions.
  • Sell anything, or take money from vendors or affiliates.
  • Call a research chemical safe or effective when the human evidence is not there.
  • Blur the line between a licensed medicine and a grey-market compound.

Grades are an editorial summary of the published evidence at the time of review, not medical advice. Evidence moves. We revise.

WTPWhat's That Peptide?

The honest, UK guide to research peptides. We index the evidence, explain the mechanisms, and grade every one by a single question: how much do we actually know in humans?

Our promise

  • Nothing for sale
  • No money from vendors
  • No dosing, ever
  • Every claim cited

The honest brief

Occasional. Honest. Never for sale.

New entries, grade changes and the odd reality check — no spam.

Not medical advice. An educational reference about research peptides for a UK audience. Most peptides here are not licensed medicines in the UK, and nothing on this site tells you to obtain, possess or use any substance. Talk to a qualified clinician before any health decision. Read the full disclaimer.

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