How we rate evidence
A single number that tells you how much human proof stands behind a peptide — before you read a word about what it supposedly does.
Peptide marketing flattens a huge range of certainty into one confident voice. Semaglutide has been tested in tens of thousands of people across trials measuring heart attacks and deaths. BPC-157 has been tested in rodents. Both are sold as "peptides", often on the same page. Our rating exists to keep that distinction visible.
The rating measures evidence, not benefit. A 5 means the evidence is strong, not that the drug is right for you — several 5-rated peptides carry serious warnings. A 1 means nobody has run the human study, not that the compound has been disproven. Read the rating and the risks together.
The scale
Very strong
23 peptidesMultiple phase 3 randomized trials plus regulatory approval in a major market.
Strong
6 peptidesConsistent human randomized trials, or approval outside the United States.
Moderate
16 peptidesSmall or early-phase human trials, or good controlled topical human data.
Limited
15 peptidesPreclinical work plus scattered human reports, uncontrolled use, or negative trials.
Minimal
13 peptidesAnimal or laboratory data only. No human efficacy evidence.
What moves a rating
- Human trials outrank animal work, always. A large and consistent rodent literature does not lift a peptide above 2. Most preclinical findings do not survive translation to humans.
- Hard endpoints outrank surrogate markers. Fractures, cardiovascular events and deaths count for more than changes in a blood marker.
- Negative trials count as evidence. A failed phase 3 raises our confidence about a compound while lowering our assessment of it. Larazotide and AOD-9604 are rated on the strength of their negative results.
- Approval outside the West is noted, not discounted. Compounds approved in Russia, China or Japan are rated on the quality of the underlying trials, which is often the limiting factor.
- Independent replication matters. Where an entire evidence base traces to one research group, the rating is capped regardless of how many papers exist.
- Route matters. Topical human data does not transfer to injection. GHK-Cu is rated on its topical evidence, and the monograph says so explicitly.