Molecule comparisons
Head-to-head on the pairs people actually weigh against each other, graded on the human evidence for the use each one is marketed for.
Every comparison reads its facts straight out of our peptide and longevity evidence matrices, so a page can never claim more than the matrix does. Where two molecules both lack human outcome data, we say so rather than picking a winner.
70 comparisons across 12 families
GH axis
CJC-1295 vs Sermorelin
Both are GHRH analogs acting on the same receptor. The real difference is regulatory: sermorelin has a pediatric clinical record and a compounding route; CJC-1295 is research-only.
GHRP-2 vs Ipamorelin
Two ghrelin-receptor secretagogues separated by selectivity. GHRP-2 pulls cortisol, prolactin and appetite along with the GH pulse; ipamorelin was engineered to leave those alone.
GHRP-6 vs Ipamorelin
Same receptor, opposite design intent. GHRP-6 is the blunt first-generation tool whose hallmark is hunger; ipamorelin was engineered to release GH with minimal spillover.
GHRP-2 vs GHRP-6
Two first-generation ghrelin-receptor peptides. GHRP-2 is the more characterized and more aggressive releaser; GHRP-6 is the one defined by how hungry it makes you.
GHRP-1 vs GHRP-6
The prototype versus the one that actually got studied. Both are early ghrelin-receptor peptides; GHRP-6 has far more human pharmacology and a defining appetite effect.
GHRP-6 vs Hexarelin
Potency versus appetite. Hexarelin is among the strongest GH-releasing peptides ever put into people; GHRP-6 is the milder relative whose hallmark is hunger. Neither is selective.
Ipamorelin vs MK-677
An injectable selective peptide against an oral small molecule. MK-677 has by far the deeper trial record, and that record is largely what argues against it.
CJC-1295 vs MK-677
Different levers on the same axis: CJC-1295 is a long-acting GHRH analog, MK-677 an oral ghrelin mimetic. Only one has been taken to outcome trials.
IGF-1 DES(1,3) vs IGF-1 LR3
Two IGF-1 analogs engineered to slip past the same binding-protein brake, one by subtracting mass and one by adding it; the real difference is duration, not evidence.
IGF-1 LR3 vs Mechano Growth Factor (MGF)
Both trade on IGF-1 biology in muscle, but one is a long-acting laboratory reagent and the other is a load-induced splice variant your own muscle already makes.
AOD-9604 vs HGH Fragment 176-191
Two forms of the same growth-hormone tail. One was developed into a named obesity drug candidate and tested in people; the other inherited the marketing without the trial record.
CJC-1295 vs Tesamorelin
Both are GHRH analogs that prompt the pituitary to release its own growth hormone. Only one is FDA-approved, and only for a narrow, specific indication.
Follistatin vs Mechano Growth Factor (MGF)
Two elegant muscle-growth mechanisms whose most impressive data belong to gene therapy and to your own genes, not to the injectable vials sold under their names.
GHRP-2 vs Sermorelin
Two different doors to the same growth-hormone pulse, a ghrelin-receptor agonist versus a GHRH analog. The gap that matters is selectivity and regulatory standing.
GHRP-2 vs Hexarelin
Close cousins at the ghrelin receptor: one is more potent, one has a defined diagnostic role, and both drag cortisol along and fade with repeated dosing.
GLP-1 / incretin
Orforglipron vs Semaglutide
One is an approved weekly injection with a cardiovascular outcomes trial behind it; the other is an investigational once-daily pill whose case rests on access, not peak efficacy.
Orforglipron vs Tirzepatide
The widest efficacy gap in the incretin class set against the widest convenience gap: an approved dual agonist injection versus an investigational once-daily tablet.
CagriSema vs Tirzepatide
An approved dual incretin agonist against an investigational amylin plus GLP-1 combination; the reported magnitudes are close, the evidence maturity is not.
CagriSema vs Retatrutide
Two investigational obesity molecules at different stages: a Phase 3 amylin plus GLP-1 combination, and a Phase 2 triple agonist holding the larger number.
CagriSema vs Semaglutide
CagriSema is semaglutide with an amylin analog added in the same weekly shot; the question is whether the second pathway earns its place, and it is not approved.
Dulaglutide vs Liraglutide
Two first-generation GLP-1s that were compared directly in AWARD-6: once-weekly convenience against a slightly larger weight effect and an obesity indication.
Exenatide vs Liraglutide
The first GLP-1 ever approved against the one that displaced it. DURATION-6 compared them directly, and the result was not close.
Semaglutide vs Tesofensine
An approved drug with pivotal trials and a cardiovascular outcomes result against a single flagged Phase 2 number that was never confirmed. The evidence gap is the comparison.
Orforglipron vs Retatrutide
Two investigational molecules pulling in opposite directions: an oral small molecule chasing access, and an injectable triple agonist chasing maximum effect.
Hormonal
Ashwagandha vs Tongkat Ali
Two botanicals sold as natural testosterone, both strongest on stress. The split is how deeply the trials replicate, and how closely the bottle you buy resembles what was studied.
Ashwagandha vs Rhodiola Rosea
Two adaptogens with genuinely different jobs: calming an over-revved stress response, versus holding mental performance together when you are already depleted.
Fadogia Agrestis vs Tongkat Ali
The famous podcast stack, pulled apart. One half has small human randomized trials; the other has rat studies that recorded organ damage alongside the testosterone rise.
Ashwagandha vs Turkesterone
An adaptogen with replicated placebo-controlled trials against a natural anabolic whose entire human record is one small acute study that found nothing significant.
DHEA vs Testosterone (TRT)
A prescription hormone therapy gated behind a diagnosis, against an over-the-counter prohormone whose real evidence sits in true deficiency, not in aging or low testosterone.
Immune / metabolic
Thymalin vs Thymosin α1
Two thymus peptides sold for immunity and longevity, separated by evidence quality: thymosin alpha-1 is an approved drug in dozens of countries, thymalin rests on one unreplicated program.
KPV vs LL-37
Both are natural human immune peptides with no controlled human trials, but they push in opposite directions: KPV dampens inflammatory signaling, LL-37 can drive it.
KPV vs Larazotide
Two gut peptides at opposite ends of the pipeline: KPV has never been tried in humans, larazotide was tried in celiac disease and its pivotal Phase 3 failed.
5-Amino-1MQ vs Adipotide
Two fat-loss compounds that never reached approved human use. One has a clean mechanism and no data in people at all; the other has a dramatic primate result and a kidney-toxicity signal.
ARA-290 vs BPC-157
Both are sold as repair peptides, but only ARA-290 has randomized human data behind it. BPC-157's entire case is rodent, and neither molecule is approved.
Metabolic / AMPK
Mitochondrial / longevity
MOTS-c vs SS-31
Both aim at the mitochondrion, but only one has been through randomized human trials, and SS-31's record is mostly misses while MOTS-c has never been tested in people.
Humanin vs MOTS-c
The two founding mitochondrial-derived peptides, graded the same way. Humanin's preclinical work is cytoprotective and neuronal; MOTS-c's is metabolic and muscular. Neither has human outcome trials.
Epitalon vs MOTS-c
Both are sold as longevity injectables with no approval, but they fail different tests: MOTS-c has credible science and no human trials, epitalon has human claims nobody has replicated.
Humanin vs SS-31
Humanin has never been through a randomized human trial; SS-31 has been through several and mostly missed their endpoints. Two different ways of not being proven.
mTOR & other
Lion's Mane vs Rhodiola Rosea
Both are sold for the brain, but for different failure modes: adding cognitive function versus keeping it from sagging when you are stressed, run down and short on sleep.
Pterostilbene vs Resveratrol
Nearly the same molecule, with one real difference: pterostilbene is far better absorbed. What neither has is human evidence that the absorption buys anything on aging.
Calcium AKG vs Spermidine
Both are preclinical stories with a striking human number attached, and in both cases the number comes from a study design that cannot carry it.
NAD⁺ & mitochondrial
Creatine vs Turkesterone
The most-studied supplement in this aisle against the least, with one clarification: creatine's human evidence is about training output, not hormones.
NAD⁺ IV therapy vs NAD⁺ precursors
Same molecule, two delivery routes. One has randomized human data for raising NAD+; the other is a clinic infusion at $250 to $1,500 a session with no controlled outcome trial.
NAD⁺ precursors vs Urolithin A
Both are sold for cellular energy, but only one has placebo-controlled trials measuring something a person might feel. NAD+ precursors move a biomarker; urolithin A moved muscle endurance.
Glutathione vs NAC (N-Acetylcysteine)
Swallow the antioxidant itself, or the precursor that lets you build it. Oral glutathione raises body stores; NAC's real credentials are medical, not the daily antioxidant capsule.
GlyNAC vs NAC (N-Acetylcysteine)
Not rival products: GlyNAC is NAC plus glycine, the second amino acid glutathione is built from. The real question is whether adding glycine buys you anything.
Methylene blue vs NAD⁺ precursors
Two approaches to mitochondrial energy with very different risk profiles: an approved drug repackaged as a biohack, versus a supplement that reliably moves a biomarker and nothing more.
Cordyceps vs Lion's Mane
Two mushrooms aimed at two different jobs, aerobic capacity versus cognition. Both rest on small, short human trials and mechanisms that still live mostly in the lab.
Creatine vs Taurine
One has hundreds of human trials behind its core claim; the other has a mouse lifespan result and a human premise a 2025 analysis failed to replicate.
Nootropic / cognitive
Selank vs Semax
Two Russian heptapeptides out of the same research tradition, split by target: Selank was studied for anxiety, Semax for stroke and cognition. Neither has Western trial data.
Noopept vs Semax
Both are Russian-registered nootropics that raise neurotrophins in animals, but one is an oral dipeptide and the other an intranasal ACTH fragment. Neither is FDA-approved.
Noopept vs Selank
Same Russian pharmacology tradition, different jobs: Noopept was developed for cognition, Selank as an anxiolytic. Both have human data that stops well short of Western standards.
Dihexa vs Semax
Not a close call but a real evidence gap: Semax has small human studies behind it, Dihexa has none, plus a growth-pathway mechanism nobody has cleared in people.
DSIP vs Selank
Sleep versus anxiety, and two very different depths of evidence: Selank has small human anxiety trials, while DSIP's basic biology is still unsettled after nearly fifty years.
Dihexa vs P21
Two preclinical nootropic peptides with no human trials at all. The only real difference is which unanswered question is bigger: safety, or what is actually in the vial.
Repair / structural
BPC-157 vs GHK-Cu
One is an injected research peptide with no human trials; the other is a copper tripeptide whose usable human evidence is topical and cosmetic. Route decides almost everything.
GHK-Cu vs TB-500
Both are sold as repair peptides, but each one's only real human data sits somewhere narrow and unrelated: a cosmetic cream for one, a dry-eye drop for the other.
BPC-157 vs Pentadeca Arginate
The same fifteen-amino-acid healing pitch twice: one molecule with a deep rodent literature behind it, and one with a near-empty file of its own.
Pentadeca Arginate vs TB-500
A rebranded BPC-157 salt with almost no literature of its own, against a peptide whose single randomized human result is about an eye drop.
GHK-Cu vs Matrixyl
Two topical peptides aimed at the same cell, the fibroblast, with plausible mechanisms, small effect sizes, and a shared dependence on whether anything crosses the skin barrier.
Argireline vs Matrixyl
Same shelf, opposite mechanisms: one tries to quiet the muscle that folds the skin, the other tries to tell fibroblasts to rebuild what folding wore away.
Collagen Peptides vs GHK-Cu
An oral supplement with placebo-controlled trials and a pooled analysis behind it, against a topical copper peptide whose human data stop at small cosmetic studies.
BPC-157 vs KPV
Two healing peptides with deep rodent literatures and no controlled human trials. The real difference is scope: BPC-157 spans tissue repair broadly, KPV is anti-inflammatory and gut-focused.
Senescence & senolytic
Fisetin vs Quercetin
Two flavonoids with senolytic reputations neither has earned in humans. Fisetin's case is entirely in mice; quercetin's belongs to a drug combination, not to quercetin alone.
Fisetin vs Spermidine
Two preclinical favorites with the same shape of problem. Excellent mouse data on both sides, and human evidence that is either not yet in or, for spermidine, already negative.
Sexual / melanocortin
Oxytocin vs PT-141
One is FDA-approved for a single narrow sexual-desire indication; the other is a famous hormone whose most-cited behavioral findings largely failed to replicate.
Kisspeptin vs PT-141
Both have been studied in hypoactive sexual desire disorder, but only one cleared the FDA. Kisspeptin remains an early-phase research tool with no approved use.
Melanotan II vs PT-141
Same melanocortin mechanism, opposite regulatory standing: bremelanotide cleared phase 3 for one narrow indication, while Melanotan II never entered that system at all.
Kisspeptin vs Oxytocin
Two genuine human hormones with real academic literatures and two different failure modes: oxytocin's famous findings did not replicate, and kisspeptin's research never reached late stage.