The Peptides Decoded A–E evidence scale
- A — Established: multiple strong human trials, often with approved use and mature outcome evidence.
- B — Good or supported: credible human evidence, but less complete, smaller or narrower than Grade A.
- C — Emerging: early human signals exist, but larger or confirmatory trials are still needed.
- D — Preliminary: limited human evidence, with much of the case resting on preclinical work or indirect data.
- E — Investigational: human efficacy evidence is absent, very weak or too uncertain for a clinical claim.
Supplements: evidence and value
Supplements Decoded separates the strength of the evidence from practical value and personal fit. Some chapter verdicts cover several outcomes with different evidence strengths. The full verdict preserves those distinctions rather than forcing a single chapter-wide letter grade.
Use the How to Read the Grades section in each book for that title’s definitions. Grades should not be treated as interchangeable across different topics or outcomes.
Evidence grade is not a recommendation
A grade describes evidence maturity. It does not establish product identity, personal suitability, prescribing authority or a recommendation to use a compound.
Regulatory status is checked separately
Approval is jurisdiction-specific and can change. Official regulator and medicine-label sources are preferred when describing an approved indication, formulation or dose. Approval of one product does not automatically apply to a different formulation or compounded preparation.
How conflicting evidence is handled
Study design, population, comparator, duration, outcome and limitations are considered before apparently conflicting findings are compared. Uncertainty is retained when the available evidence cannot support a firm conclusion.
Automation and editorial responsibility
Digital tools may assist with organisation, consistency checks and production. They do not replace source verification or editorial responsibility. Claims, metadata and references remain subject to human review.