The most searched peptide in the biohacking world. Over 500 studies, isolated from human gastric juice, with strong preclinical evidence for gut and tendon healing. Fewer than 30 human subjects across all published trials.

A 7-amino-acid synthetic fragment of the body's own wound-healing protein. One of the most popular recovery peptides in sport. Strong preclinical data for tissue repair. WADA prohibited. Used widely by athletes despite ban.

Three amino acids from alpha-MSH that block NF-κB without suppressing immunity. Absorbed selectively by inflamed gut tissue via PepT1 transporter. Strong colitis animal data. Best adjunct for gut and skin inflammation. No human trials yet.

The world's most-consumed therapeutic peptide. Pro-Hyp dipeptides directly stimulate fibroblast collagen synthesis. Multiple RCTs: skin elasticity, joint pain, tendon recovery. FDA GRAS status. Safest entry in this book.

The most clinically substantiated immune-modulating peptide in this book. 35+ country approvals, FDA orphan drug status, 30+ trials and 11,000+ subjects. Hepatitis B, cancer immunotherapy, HIV, and sepsis. Safety profile "indistinguishable from placebo."

The thymic signal that needs zinc to speak. Biologically inactive without its zinc cofactor — immune decline may be partly a zinc deficiency. One human trial (1982), unreplicated. Zinc 15mg/day measurably restores thymulin activity without injection.

Three amino acids from cartilage tissue that regulate chondrocyte gene expression at the DNA level. Upregulates collagen type II and aggrecan. Russian research only — no Western RCTs. Preventive tool for early-stage OA. Best stacked with BPC-157.

The most clinically proven weight-loss class in history. Semaglutide: 15% weight loss. Tirzepatide: 20%+. Cardiovascular mortality -20%. Fatty liver treatment. Potential Alzheimer's and addiction applications. A $53B drug class redefining medicine.

The most consequential peptide of the decade. 15% mean weight loss in Phase III. SELECT trial: 20% reduction in cardiovascular death, heart attack, and stroke. First obesity drug approved for cardiovascular risk reduction.

The weight loss record holder. First dual GLP-1/GIP agonist — 20.2% mean weight loss vs semaglutide's 13.7% in the 2025 NEJM head-to-head trial. Also FDA-approved for sleep apnoea. CVD cardiovascular outcome data (TRIUMPH) expected 2026–2027.

The fat-burning fragment of growth hormone — no IGF-1, no insulin effects. Strong animal data. A failed Phase 2b human trial. Development abandoned 2007. Still one of the most popular fat-loss peptides in the community.

Growth hormone's most powerful anabolic messenger. Drives muscle hypertrophy via mTOR. Documented cancer risk with chronic elevation. The Laron paradox: IGF-1 deficiency protects against cancer. WADA banned. High risk — read fully.

The most clinically validated GHRH analogue. FDA-approved with Phase III data showing 15–20% visceral fat reduction. DPP-4 resistant — more potent than sermorelin. New EGRIFTA WR long-acting formulation approved March 2025.

The smarter way to raise growth hormone. Tells your pituitary to make its own GH rather than replacing it — regulated by somatostatin feedback, impossible to overdose. Preferred by anti-ageing physicians over direct rhGH for long-term protocols.

The convenience GH peptide. DAC modification binds albumin for a 6–8 day half-life — one or two weekly injections sustains elevated GH baseline. Phase II trial: 2–10x GH increase for 6 days. Traded physiological pulsatile rhythm for convenience.

The most popular GH secretagogue stack. CJC-1295 sustains the baseline via GHRH receptors (6–8 day half-life). Ipamorelin fires clean GH pulses via ghrelin receptors without cortisol or prolactin effects. Together: 3–5x more GH than either alone.

The physiological GHRH choice. Fires a 30-minute GH pulse then stops — unlike CJC-1295 DAC's 6–8 day continuous elevation. Combined with ipamorelin (the saturation dose) it produces 3–5x more GH. The most controllable GH protocol.

First-generation GH secretagogues. GHRP-2 raises cortisol; GHRP-6 drives intense hunger. Both superseded by ipamorelin for most goals. GHRP-6 hunger remains useful for caloric surplus during mass-building phases.

Targets the inner mitochondrial membrane, stabilising cardiolipin to restore energy production. The first FDA-approved mitochondria-targeted therapy (2025). Studied for heart failure, muscle wasting, kidney disease, and ageing.

A peptide encoded by mitochondrial DNA itself. Rises 12-fold during exercise and declines with age. Activates AMPK — the master metabolic switch — improving insulin sensitivity and extending lifespan in animal models.

Mitochondria-derived cytoprotective peptide. Declines with age. Studied for neuroprotection, Alzheimer's, and metabolic health. Higher levels linked to longevity in centenarian offspring.

Russia's most-used nootropic peptide. Boosts BDNF, modulates 1,500+ genes in stroke models, approved in Russia since 1996. Acute focus and clarity reported within 30 mins. Strongest evidence base of any cognitive peptide.

Anxiolytic comparable to benzodiazepines — without sedation, amnesia, or dependence. Head-to-head RCT against medazepam in 62 GAD patients. Approved Russia and Ukraine. The most credible anti-anxiety peptide.

Semax with an adamantane cage bolted on — better BBB penetration, longer half-life, theoretically more potent. The most advanced Semax derivative. Almost all evidence extrapolated from parent compound. No human trials exist.

Most clinical evidence of any cognitive peptide — Cochrane reviews, 6-trial Alzheimer's meta-analysis, approved in 50+ countries for stroke and dementia. Not FDA approved. IV only. The regulatory paradox of the peptide world.

Isolated from sleeping rabbits in 1974. Promotes deep delta-wave sleep without sedation. 50 years of research — no gene or receptor ever found. FDA Category 2. The enduring mystery peptide of sleep science.

A 3-amino-acid Khavinson bioregulator derived from pineal gland tissue. Proposed to enter cell nuclei and restore circadian and neuroprotective gene expression. Russian research only. No Western RCTs.

The body's master anti-inflammatory switch — suppresses cytokines, generates regulatory T cells, prevents septic shock in animal models. Used clinically for CIRS and pulmonary hypertension. Monitor blood pressure. Do not use during active infection.

The most studied longevity peptide — Khavinson's 40-year programme. Activates telomerase, extends telomeres in human cells, reduced mortality 27% in 15-year Russian trial. No independent Western replication. Remarkable if true.

Kills senescent zombie cells by disrupting the FOXO4-p53 survival mechanism. Restored fitness and kidney function in aged mice. Most targeted longevity peptide — and most dangerous to get wrong. No human trials.

The best-evidenced cosmetic peptide in existence — multiple RCTs confirm skin rejuvenation. A natural tripeptide that declines with age and modulates 31% of human genes. Topically proven. Injectable form restricted in US since 2023.

The only FDA-approved desire treatment that works in the brain, not blood vessels. MC3R/MC4R agonist — enhances desire via dopamine pathways, not vascular mechanics. Effective for women with HSDD and men who don't respond to PDE5 inhibitors.

The most famous neuropeptide — and most misunderstood. Not a bonding drug but a social context amplifier. FDA-approved (obstetric) since the 1960s. Investigational for autism, PTSD and anxiety. Reality is more nuanced than the headlines.

Developed for tanning, infamous for erections. Non-selective melanocortin agonist — ancestor of FDA-approved bremelanotide. Grey-market tanning and arousal use. Melanoma cases documented. Safer alternatives exist for sexual use.

The only known human antimicrobial peptide. Your skin and mucous membranes' first line of defence. Kills bacteria, fungi and viruses directly. Modulates wound healing, angiogenesis, and innate immune signalling. Studied for chronic infections and immune deficiency.

The full 43-amino acid protein that TB-500 is derived from. Beyond tissue repair: cardiac regeneration after MI, corneal wound healing, and systemic immune regulation. Acts through actin sequestration, ILK activation, and angiogenesis. More complete mechanism than TB-500 alone.

A family of 2-4 amino acid peptides developed by Prof. Vladimir Khavinson at the St. Petersburg Institute of Bioregulation. Each targets a specific organ or tissue at the gene level — heart, lung, liver, pancreas, prostate. Cartalax, Thymulin and Pinealon are already in the book; this entry covers the full family.

The GLP-1 analogue that proved the class. Daily injection, 97% homology with human GLP-1, ~13-hour half-life, two FDA approvals (type 2 diabetes as Victoza 2010; obesity as Saxenda 2014). The LEADER cardiovascular outcomes trial established GLP-1 agonists as cardioprotective agents. The clinical foundation on which semaglutide and tirzepatide were built.

The most potent growth hormone-releasing peptide — produces significant GH release even after repeated administration without the cortisol/prolactin blunting seen in GHRP-2/6. Unique GH-independent cardioprotective effects via specific cardiac receptors. Developed 1972. The GHRP you reach for when you need maximum GH pulse.

The oral GH secretagogue — not technically a peptide but works identically. Once-daily pill that raises GH and IGF-1 for 24 hours. Enormous community use. Merck Phase 2 data: significant lean mass increases, bone density, sleep quality. WADA banned. The alternative for people who won't inject.

The natural brake on muscle growth — by inhibiting myostatin, follistatin removes the ceiling. Animals without myostatin have twice the muscle mass. 8 weeks of follistatin treatment increases muscle mass ~10% in models. High community interest as a lean mass tool without androgenic effects.

The most exciting new weight-loss molecule in development. A single molecule combining GLP-1 receptor agonism with amylin receptor agonism. Phase 1 results: 22% body weight reduction in 12 weeks — faster and deeper than any approved drug. The amylin component slows gastric emptying and reduces glucagon independently of GLP-1. Potentially beyond retatrutide.

A newly discovered family of mitochondria-encoded peptides — cousins of Humanin and MOTS-c — found in 2023-24. Encoded within the 16S rRNA region of the mitochondrial genome. SHLP-2 extends lifespan in multiple model organisms. SHLP-6 regulates glucose metabolism. The mitochondrial peptidome is turning out to be far larger than anyone anticipated.

The most potent nootropic peptide known — reportedly 7 million times more potent than BDNF itself in promoting synaptogenesis. Derived from angiotensin IV. Half-life of ~13 days. Promotes neuroplasticity, memory formation, and neuroprotection in rodent models. Oral and transdermal active. Human data extremely limited — but the mechanistic case is compelling.

The USC discovery that activated ERRα and ERRγ nuclear receptors — producing cardiac adaptations normally only seen in trained athletes, in untrained sedentary animals. Distinct from AICAR's AMPK mechanism: targets the estrogen-related receptor pathway. Reduced age-related cardiac decline in mouse models. Genuinely novel mechanism with no known analogues.

Novo Nordisk's answer to retatrutide: co-formulated cagrilintide (long-acting amylin analogue) plus semaglutide 2.4mg in a single weekly injection. REDEFINE Phase 3 data shows ~24% weight loss — matching tirzepatide and approaching retatrutide. Two complementary mechanisms: GLP-1 appetite suppression + amylin-mediated satiety and glucagon control.

A small peptide derived from the loop domain of BDNF. Acts as a fast-acting antidepressant in rodent models through TrkB receptor activation — without the side effects of SSRIs or the dissociation of ketamine. Promotes neuroplasticity and synaptogenesis. Growing community interest as an alternative to conventional antidepressants. Human trials not yet underway.

Fragments derived from αKlotho — the protein that when overexpressed extends lifespan by 30% in mice. The KL1 domain peptides recapitulate many of Klotho's benefits: cognitive protection, antagonism of IGF-1/insulin signalling in the brain (which paradoxically improves cognition), and potential cardiovascular protection. Single injection in old mice improved cognition for weeks.

A naturally occurring peptide derived from sortilin that antagonises TREK-1 potassium channels — a completely novel antidepressant mechanism. TREK-1 overactivity is implicated in depression; blocking it produces rapid antidepressant effects in models without the delayed onset of SSRIs. Discovered by French researchers. No side effects seen in animal models. Human trials not yet begun.