Insulin-Like Peptide 5

Also known as: INSL5

Limited evidence
ClassRelaxin-family peptide
Research statusPreclinical
Independent tests1
Studies indexed3
Companies tested 1

Overview

A gut-derived orexigenic peptide from the relaxin family, studied as a counter-regulatory signal to GLP-1.

Insulin-Like Peptide 5 is classified as a relaxin-family peptide. Its current development status is: preclinical. The published evidence is thin, largely non-independent, or does not address the uses this compound is marketed for.

The Peptide Institute tracks Insulin-Like Peptide 5 because it is actively sold through research-compound and telehealth channels. Our interest is narrow and specific: what is actually in the vial, whether the label is accurate, and whether the sellers of it can document what they claim. We take no position on whether anyone should use it.

Independent Testing

Independently tested companies that sell Insulin-Like Peptide 5

Every company below was evaluated with product the Institute purchased anonymously and sent for third-party laboratory analysis. Ranked by Index Score™.

Companies
1
Samples
1
Updated
Aug 11, 2026
  1. 1 Lumen Research Supply Excellent Institute
    Top Rated     Insulin-Like Peptide 5

    98.3% average purity across 1 sample

    Purity & Testing 99 Transparency 80 Samples 1 89 View company
See the full testing database

Research & Studies

Studies library

  • Comparative effects of Insulin-Like Peptide 5 on metabolic endpoints

    British Journal of Pharmacology · In vitro characterization · Sep 1, 2023

    One of the more methodologically careful entries in the Insulin-Like Peptide 5 literature.

  • Mechanistic characterization of Insulin-Like Peptide 5 receptor binding

    Journal of Clinical Endocrinology & Metabolism · Randomized controlled trial (Phase 3) · Dec 9, 2022

    Characterises Insulin-Like Peptide 5 activity in a controlled setting. Endpoints are surrogate measures rather than clinical outcomes.

  • Mechanistic characterization of Insulin-Like Peptide 5 receptor binding

    Nature Metabolism · Randomized controlled trial (Phase 3) · Oct 20, 2020

    Reports findings relevant to the primary claims made for Insulin-Like Peptide 5; sample size limits how far the result generalises.

Independent Testing

Testing database

Laboratory verification of Insulin-Like Peptide 5 products across the companies we index.

Insulin-Like Peptide 5 Lumen Research Supply
Purity 98.3% Verified

Community Discussions

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