Guides
Educational guides
Start here if peptides are new to you. These cover the fundamentals, how to judge the evidence behind a claim, and the practical handling details that determine whether anything works at all.
What are peptides? And are they safe?
A plain-language definition, how peptides differ from proteins and steroids, the main categories, and a four-question framework for judging whether a specific compound is safe.
Read guideGLP-1 peptides: semaglutide, tirzepatide and retatrutide
Mechanism, dosing, side effects and trial evidence for the three incretin-class peptides that dominate metabolic research.
Read guidePeptide Evidence Index 2026
Compare human evidence, clinical-trial status and regulatory status across all 20 PeptideIndex compounds.
View the indexPeptides 101: how peptides work, signal cells and differ from other compounds
How peptide signalling works at the receptor level, why mechanism does not equal clinical effect, and how to read a mechanism claim critically.
Read guideCJC-1295 DAC vs no DAC: what's the difference?
What the Drug Affinity Complex does to CJC-1295, how albumin binding changes its pharmacokinetics, why the no-DAC naming is inconsistent, and what the evidence does and does not show.
Read guideBPC-157 human studies: what does the evidence show?
What human evidence actually exists for BPC-157, how it differs from the animal and mechanistic research it is usually confused with, and what can honestly be concluded.
Read guideTB-500 human evidence: what do the studies show?
Review the human evidence for TB-500 and thymosin beta-4, including clinical research, injury-healing claims, animal studies and major evidence limitations.
Read guideSafety, risk and how to read the evidence
How to tell a clinically validated peptide from a marketing story, and the risks that actually matter.
Read guideStorage, reconstitution and handling
Why most peptide failures are handling failures, and how the cold chain actually works.
Read guideBacteriostatic water for peptides: what it is and how much to add
What bacteriostatic water is, why it is used for peptide reconstitution, how much diluent to add, and how changing the volume changes concentration.
Read guideStacking and cycling: combining peptides sensibly
Why some combinations are synergistic, why more is rarely better, and how cycling protects receptor sensitivity.
Read guidePeptide glossary
The terms that show up constantly in peptide research and product listings, defined plainly.
Read guideRetatrutide clinical trials: what does the evidence show?
What human trials of retatrutide have measured, what the phase 2 studies and the reported 2026 phase 3 TRIUMPH results show for body weight, glycaemic control, cardiovascular endpoints and adverse events, and where the evidence still stops.
Read guideRetatrutide weight loss: what do clinical trials show?
The body-weight results actually reported in retatrutide human trials — phase 2 and the 2026 phase 3 TRIUMPH readouts — including dose-response, how many participants reached large weight-loss thresholds, and what the numbers do not tell you.
Read guideRetatrutide side effects: what do clinical trials show?
Adverse events actually reported in retatrutide human trials — gastrointestinal effects, heart-rate changes, discontinuations and dose-related patterns — and how trial safety data differs from mechanistic risk and anecdotal claims.
Read guideRetatrutide UK: approval, availability and legal status
Whether retatrutide is approved by the MHRA, whether it can be prescribed in the UK, what research-use-only sales actually mean, and why being purchasable online is not the same as being authorised.
Read guideGrowth Hormone Peptides: CJC-1295, Ipamorelin & Tesamorelin
What growth hormone peptides are, how CJC-1295, ipamorelin and tesamorelin differ in mechanism and regulatory status, and how far the human evidence actually goes for each.
Read guideGHK-Cu: skin, hair and human evidence
What the evidence actually shows about GHK-Cu for skin and hair — which findings come from laboratory work, which from human studies, and what remains uncertain.
Read guideLongevity Peptides: What Does the Evidence Actually Show?
Compare Epitalon, SS-31, MOTS-c and NAD+ for longevity and healthy aging, including human evidence, animal research, mechanisms and major limitations.
Read guidePeptides vs Steroids: Key Differences in Mechanism, Evidence and Risk
Compare peptides vs anabolic steroids, including how they work, muscle-building evidence, hormonal effects, side effects and whether peptides are actually safer.
Read guidePeptide Half-Life Explained: What It Means and Why It Matters
Learn what peptide half-life means, why half-lives vary, how half-life differs from duration of action, and why a longer half-life does not necessarily mean better.
Read guideNootropic Peptides: Semax & Selank Explained
Explore nootropic peptides including Semax and Selank, how they differ, proposed mechanisms, human cognitive research and the major limitations of the evidence.
Read guideRecovery Peptides: BPC-157, TB-500 & GHK-Cu Explained
Compare BPC-157, TB-500 and GHK-Cu for recovery and tissue repair, including human evidence, animal research, mechanisms and major limitations.
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