Sourcing and Citation Policy

A claim is only as trustworthy as the source behind it. This policy defines exactly which sources Peptevity treats as evidence, which it uses only for context, and which it refuses to cite at all. It governs both the inline citations that back every graded claim and the outbound links we place. This page is research and educational information, not medical advice.

The source hierarchy

We rank sources by what they can legitimately support. A claim must be backed at the highest tier available for that claim.

Tier 1 — Primary evidence (used to support efficacy and safety claims)

These are the only sources that can carry an evidence grade:

• Peer-reviewed primary research and systematic reviews indexed on PubMed and the full text on PMC (NIH/NCBI). The animal-vs-human distinction is read directly from the study, not from a summary of it.
• Registered clinical trials and trial results, cited by name and registry where available.
• Regulatory primary sources — the U.S. Food and Drug Administration, Health Canada, and official rulemaking and advisory records (for example, the 503A Category 2 review and PCAC hearing record).

Tier 2 — Authoritative secondary sources (used for context and corroboration)

These are trusted institutions we cite for general physiology, safety framing, and entity grounding — but not as a substitute for the primary study behind a specific efficacy claim:

• Examine.com — a peer evidence-grading reference.
• Cleveland Clinic, Mayo Clinic, and Harvard Health.
• DoD Operation Supplement Safety (OPSS) — regulatory and safety posture.
• Wikipedia — entity grounding only; never the sole support for a health claim.

Tier 3 — Attributed expert commentary (used as a named voice, not as evidence)

Quoted, named, credentialed experts can add interpretive context. Their commentary is attributed by name and credential and never used to upgrade an evidence grade — an expert's opinion that a Grade C compound is promising does not make the evidence human.

What we never cite or link to

This list is a firewall, not a preference:

• No vendor or seller pages, ever — not as a citation, not as an outbound link, not as a "where to learn more." Peptide sellers have a financial interest in the claims we are evaluating, which disqualifies them as a source about those claims.
• No affiliate links and no purchase facilitation. We do not earn from any transaction, and we do not point readers toward one. See our conflict-of-interest and funding disclosure.
• No vendor "studies" or sponsored white papers presented as independent research.
• No forum, Reddit, Quora, or testimonial content as evidence. We may note that a claim circulates anecdotally — and grade it E — but anecdote is never cited as if it demonstrated an effect.
• No AI-generated summaries standing in for a primary source. Every cited claim traces to a real, human-verifiable document.

How citations appear on the page

• Inline and specific. Citations sit at the point of the claim they support, linked to the primary source — not collected in a vague reference dump at the bottom.
• Species and study type are stated in-text. "In a rat study (PMC link)…" rather than a bare citation that hides whether the work was in animals or humans.
• Regulatory citations are dated. Any FDA or Health Canada status carries the date it was verified, because that status changes.
• One claim, the strongest available source. Where multiple sources exist, we cite the highest-quality one — a systematic review over a single trial, a single human trial over an animal study — and grade accordingly.

Verifying and refreshing sources

• Links are checked on publication and on each scheduled review. A dead or moved primary source is repaired, not silently dropped.
• When a newer, higher-quality study changes the evidence picture, we update the claim, its grade, and the citation, and log the change under our corrections policy.
• Last-reviewed dates on every page reflect the last time the sourcing was confirmed current.

Frequently asked questions

Why won't Peptevity link to where I can buy a peptide? Because linking to or citing sellers would convert a neutral reference into a conflicted one. We sell nothing, earn nothing from any transaction, and link only to non-commercial allies — regulators, primary research, and trusted institutions. Sourcing decisions and buying decisions are kept completely separate.

Do you cite other peptide websites? We cite peer evidence references such as Examine for context and corroboration, but never vendor blogs, and never another secondary site in place of the primary study a claim actually rests on. Efficacy and safety claims must trace to primary research or a regulator.

Why do you keep saying "in rats" or "in cell culture" in the citations? Because the species and study type are the single most important fact for judging whether a finding means anything for people. Hiding it inside a citation number is exactly how animal data gets mistaken for human evidence — so we state it in the sentence.

How recent are your sources? Efficacy citations are tied to the best available study regardless of age, but regulatory citations are dated to their last verification and reviewed on a recurring cadence, since legal status changes faster than the underlying science.

Related editorial standards

• Evidence-grading methodology — the grades these sources support.
• Editorial standards — how claims are written and structured.
• Conflict-of-interest and funding — why no source is a seller.
• Corrections policy — how source and grade changes are logged.
• Medical disclaimer and RUO statement — research-use-only framing.
• The Peptevity Research Desk — authorship and the reserved reviewer slot.