The practical answer
Write the exact claim, find the study it cites, and check whether that study measured the same thing in the same kind of subject. A cell or animal result, a planned trial and a completed trial with results are different evidence; none of them is FDA approval, which is a separate review step.
Evidence, method & source dates ↓The short answer
Most peptide marketing claims fail on a mismatch, not a fabrication: a real study exists, but it measured something else, in different subjects, or has not reported results. Your job is to place the cited source on the development ladder and compare its measured outcome with the claim's wording.
FDA describes drug development as five steps: discovery and development, preclinical research, clinical research, FDA drug review, and post-market safety monitoring. A citation from step 2 cannot carry a claim that requires step 3, and nothing before step 4 amounts to approval. [3]
Claim type versus evidence that would address it
Use this map before reading the study in detail.
| Claim wording | Evidence that could address it | Evidence that cannot |
|---|---|---|
| 'Acts on receptor X' | Laboratory (in vitro) study measuring that interaction | Nothing about effects in people |
| 'Shown in animals' | Preclinical (in vivo) study in the named species | Any human outcome |
| 'Studied in humans' | A clinical study record with the substance | Evidence it worked, unless results are reported |
| 'Improves outcome Y in adults' | Completed controlled trial reporting outcome Y in adults | Trials measuring a different marker or population |
| 'FDA approved' | FDA approval record for that product | Any study, registry entry or phase label |
What the phases mean, in FDA's numbers
FDA summarizes typical trial size, length and how many drugs move on. The attrition column is the useful part: most candidates that enter clinical research never reach the next phase. [1]
| Phase | Typical participants | Typical length | Main question | Share moving on |
|---|---|---|---|---|
| 1 | 20 to 100 healthy volunteers or people with the condition | Several months | Safety | About 70% |
| 2 | Up to several hundred people with the condition | Several months to 2 years | Efficacy and side effects | About 33% |
| 3 | 300 to 3,000 people with the condition | 1 to 4 years | Efficacy and adverse reactions | About 25 to 30% |
| 4 | Several thousand people with the condition | Not stated | Safety and efficacy after approval | Not applicable |
Read these fields from the study
FDA notes that a clinical protocol defines who qualifies, how many take part, duration, whether there is a control group, what assessments are made and how data are analyzed. Those are the fields to copy into your note. FDA also says preclinical studies are usually not very large, so record the sample size whatever the stage. [1][2]
- Source type: registry record, protocol, preprint, peer-reviewed paper, or posted results.
- Subjects: cells, species, or human population with inclusion criteria.
- Planned versus analyzed number of participants.
- Control or comparison group, if any.
- Outcome actually measured, in the study's own words.
- Whether results are reported; if not, write 'no results in source on [date]'.
Worked example with invented claims
A fictional seller says 'shown to improve recovery in adults' and links to a registry entry for a planned trial. Map it: source type is registry, results not reported, measured outcome not yet available. Conclusion: the link supports 'a human study was planned', nothing more. Do not record it as a negative result either.
A second fictional claim, 'clinically proven', cites a paper reporting a change in a blood marker in 14 people with no control group. Map it: phase-1-sized, uncontrolled, measured a marker rather than the claimed everyday outcome. Write both outcomes side by side; the gap is the finding. It says nothing about how any individual would respond.
Write a bounded conclusion
A good note reads like: 'Source is [type], [subjects], measured [outcome]; claim asserts [different outcome]; unsupported by this source as of [date].' Do not score evidence by counting citations, and do not treat a research-grade product as equivalent to the material in a study. Keep the original claim and your dated note; if the study later posts results, append rather than overwrite.
Who this fits: anyone checking a supplier or forum claim before repeating it. Who should go elsewhere: anyone making a personal health decision should talk to a qualified clinician; this guide gives no medical, dosing or use advice and makes no claim of benefit for any peptide. Based on FDA pages accessed October 29, 2026.
Check the underlying evidence
Sources & review dates
- FDA: Step 3, Clinical Research ↗Accessed 29 Oct 2026
- FDA: Step 2, Preclinical Research ↗Accessed 29 Oct 2026
- FDA: The Drug Development Process ↗Accessed 29 Oct 2026
Sources are documentary evidence. They do not establish firsthand testing of a listed supplier.