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Reading the research
What the A–D evidence grades mean
How this site grades the research behind each peptide, and what a grade doesn't say.
- A, strong human evidence: at least two randomized controlled trials (or a meta-analysis) with several hundred people, pointing the same way.
- B, some human evidence: controlled human data, but limited, early or conflicting.
- C, mostly animal studies: no controlled human trials; the evidence comes mainly from animals or uncontrolled human reports.
- D, little or no evidence: cell studies, a single animal study or nothing relevant.
A grade rates how strong the evidence is, not whether the result was good: consistently negative large trials also earn an A. Only studies of the exact molecule count, and every grade comes with a one-line reason on the site.
Key points
- Grades measure evidence strength, not benefit.
- A needs multiple sizeable RCTs.
- Each grade has a stated reason.
Quick check
Large, consistent trials show a compound doesn't work. What grade does its evidence get?
Grades rate evidence strength. Strong evidence that something fails is still strong evidence.
Full grading rules · Grades for every peptide
General education, not medical advice. Nothing here recommends using any compound or amount.