Peptides Explained

Evidence: how to judge a health claim

In short

Reading the whole page takes about 2 minutes.

  • A claim is only as good as the study behind it. These pages show you how to check.
  • A result in rats or cells is a first step. It does not show what works in people.
  • We grade evidence on four separate questions. We never add them into one score.
  • Who paid for a study matters. It does not make a result false, but it calls for checks.
Last reviewed
A tall wooden ladder made of poles, seen from below, leaning against a pale wall in front of large green banana leaves.
A wooden ladder. Cell and animal studies are the lowest steps of the evidence ladder. Photo: Nadinviki (Wikimedia Commons) CC BY-SA 4.0 Image details

Why read about evidence?

Because many claims about peptides rest on small animal studies. These pages show how to check them.
Four questions to ask of any claim, and the page that answers each one.
Your questionRead
What kind of study is this, and what can it show?How to read a study
It worked in rats. Will it work in people?The translation gap
How strong is the evidence for this compound?Evidence grading
Who paid, and does that matter?Conflicts of interest

Many peptides sold outside pharmacies, such as BPC-157, TB-500 and KPV, have been studied almost only in cells and animals. Some have hardly been studied at all.1,2,3 Animal studies are a real start. But in one large review, only 5 in 100 treatments tested in animals were later approved for use in people.4

Who paid matters too. Studies paid for by a company more often report good results for its product.5 That does not make them wrong. It means someone independent should check.

These pages give no doses and no advice on what to use. They help you judge what you read. If you already use a product, see product risk and the warning signs.

The evidence pages

Where should I start?

Start with how to read a study. The other pages build on it.
  • How to read a study

    From cell dishes to large trials: what each kind of study can answer, and the questions to ask of any abstract or headline before you trust it.

  • The translation gap

    Why results in rats and mice so often fail in people: species differences, lab-made injuries, small biased studies, and why animal doses do not scale.

  • Evidence grading

    The rubric behind every evidence profile on this site: four separate axes, the thresholds for each, the claim badges, their limits and how a grade changes.

  • Conflicts of interest

    How to spot a sponsored study, a seller's review, a paid expert or influencer, ghost-writing and predatory journals, and how much checking a conflict calls for.

Sources

Every claim on this page links to one of these sources. Scholarly sources link to their DOI; regulatory sources to the regulator's own page.

  1. U.S. Food and Drug Administration (2026). FDA Briefing Document for BPC-157-Related Bulk Drug Substances (BPC-157 (free base) and BPC-157 acetate), Pharmacy Compounding Advisory Committee meeting, 23–24 July 2026. Regulator fda.gov — accessed 20 October 2026 ↩
  2. U.S. Food and Drug Administration (2026). FDA Briefing Document for TB-500-Related Bulk Drug Substances (TB-500 (free base) and TB-500 acetate), Pharmacy Compounding Advisory Committee meeting, 23–24 July 2026. Regulator fda.gov — accessed 20 October 2026 ↩
  3. U.S. Food and Drug Administration (2026). FDA Briefing Document for KPV-Related Bulk Drug Substances (KPV (free base) and KPV acetate), Pharmacy Compounding Advisory Committee meeting, 23-24 July 2026. Regulator fda.gov — accessed 20 October 2026 ↩
  4. Ineichen BV, Furrer E, Grüninger SL, Zürrer WE, Macleod MR (2024). Analysis of animal-to-human translation shows that only 5% of animal-tested therapeutic interventions obtain regulatory approval for human applications. PLoS Biology 22:e3002667. Research article doi:10.1371/journal.pbio.3002667 ↩
  5. Lundh A, Lexchin J, Mintzes B, Schroll JB, Bero L (2017). Industry sponsorship and research outcome. Cochrane Database of Systematic Reviews 2:MR000033. Review doi:10.1002/14651858.MR000033.pub3 ↩