Research areas
Evidence by research area
Body composition
Fat loss and lean mass claims are the most common reason people search for peptides. The evidence ranges from large approved-drug trials to zero human data, depending on the peptide.
Cognitive research
Cognitive claims for peptides — focus, memory, neuroprotection — are almost entirely preclinical. GLP-1 drugs are the exception, with large Alzheimer's trials now reporting.
Healthy aging research
"Longevity" claims for peptides rest on animal lifespan studies and hormone-level surrogates. No peptide has human evidence of extending lifespan or healthspan.
How to interpret studies
A reader's guide to peptide research: study types, what animal models can and cannot tell you, common statistical traps, and how marketing misuses real papers.
Immune research
Thymic peptides have a long, mixed history in immunology; the popular "immune-boosting" peptides sold online have little or no human evidence for immune outcomes.
Metabolic health
GLP-1 and dual-incretin peptides have transformed metabolic medicine with large trials and FDA approvals; almost every other "metabolic" peptide claim rests on far weaker evidence.
Peptide safety
What is known about the safety of approved peptides from their trials and labels, and why "no reported side effects" for unapproved peptides usually means "no one has looked".
Recovery and tissue repair
What peptide research actually shows for tendon, ligament, muscle, gut and wound healing — mostly animal data, with a few small human studies and one approved topical use.
Regulation and approval
How the FDA classifies peptides — approved drugs, investigational agents, compounding-eligible substances, and "research use only" products — and why the categories matter for evidence and safety.
Sexual health
Bremelanotide (PT-141) is FDA-approved for hypoactive sexual desire disorder in premenopausal women; its use in men and for erectile dysfunction is not approved and rests on older, smaller studies.
Skin and hair
Topical copper peptides and oral collagen peptides have small human trials for skin; hair-growth claims for peptides rest almost entirely on animal and cell studies.