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DPreclinical / mechanistic only
No human data

Humanin

Humanin is a 24-amino-acid mitochondrial-derived peptide (MDP) encoded within the 16S rRNA region of mitochondrial DNA. Endogenously it acts as a cytoprotective/anti-apoptotic stress-response signal, and circulating levels decline with age. It is marketed to consumers and biohackers as an injectable "longevity," metabolic, or neuroprotective peptide, but this use is not supported by human evidence. There are no published human interventional trials, no human safety/toxicology data, no established dose, and no regulatory approval for administering humanin or its synthetic analogs (e.g., HNG/S14G-humanin) to people. Essentially all efficacy claims come from cell-culture and rodent experiments; the only human data are observational correlations of naturally occurring blood levels with age, insulin/growth-hormone axis activity, coronary endothelial function, and sperm quality. Because product identity, purity, sterility, dosing, and long-term effects in humans are entirely uncharacterized, the realistic dangers are those common to unregulated injectable research peptides: injection-site infection, contamination/endotoxin reactions, immunogenicity, and wholly unknown systemic effects. Anyone considering or using it should treat it as an experimental substance with no human safety net and involve a physician.

Clinical readoutPeptide · mitochondrial-peptide
Hepatic strainNone
CardiovascularNone
HPTA suppressionNone
Half-life
Not characterized…
Route
No approved human route
Evidence
D
Active
Unknown in humans
1·t½2·t½3·t½4·t½5·t½
Illustrative single-compartment washout · each mark = one half-life · t½ ≈ Not characterized in humans. Native humanin is a small unmodified peptide expected to be rapidly degraded by peptidases with a short circulating half-life (minutes); synthetic potency-enhancing analogs such as HNG (S14G-humanin) were engineered partly to improve stability/potency in animal models. No validated human half-life exists.
Pharmacology

Mechanism of action

Humanin is translated from a short open reading frame in the mitochondrial 16S rRNA (MT-RNR2) gene. It is a retrograde (mitochondria-to-cell) signaling peptide. Proposed mechanisms, characterized largely in vitro and in animals, include: (1) binding a trimeric cell-surface receptor (CNTFR/WSX-1/gp130) to activate STAT3 signaling; (2) antagonizing pro-apoptotic Bcl-2-family proteins (notably BAX and BID/tBID), blocking mitochondrial outer-membrane permeabilization and caspase activation; (3) reducing reactive oxygen species and protecting against oxidative, hypoxic, serum-starvation, and amyloid-beta insults; and (4) central (hypothalamic STAT3-dependent) improvement of peripheral insulin sensitivity and suppression of hepatic glucose output in rodents. In humans the peptide's mechanistic role is inferred from correlational data only.
Kinetics

Pharmacokinetics

Half-life

Not characterized in humans. Native humanin is a small unmodified peptide expected to be rapidly degraded by peptidases with a short circulating half-life (minutes); synthetic potency-enhancing analogs such as HNG (S14G-humanin) were engineered partly to improve stability/potency in animal models. No validated human half-life exists.

Active duration

Unknown in humans. In rodent studies single injections produced acute metabolic effects, but no human duration-of-effect data exist.

Route

No approved human route. Research/animal administration has used intracerebroventricular, intravenous, intraperitoneal, and subcutaneous injection; consumer use is typically subcutaneous injection of reconstituted lyophilized peptide of unverified identity/purity.

Metabolism & clearance

Presumed proteolytic degradation to constituent amino acids, as for other small peptides; specific metabolic pathways, clearance organs, and renal handling in humans are not established. PK data here are for washout/monitoring context only and must not be used to time or evade drug testing.

For monitoring and washout planning, not drug-test evasion.

Reported effects

Physiological & performance effects

  • Endogenous humanin is an anti-apoptotic, cytoprotective mitochondrial stress-response peptide whose blood levels decline with age in humans and mice (observational).
  • Higher endogenous circulating humanin is associated with lower growth-hormone/IGF-1 axis activity; GH or IGF-1 administration lowered humanin levels in human subjects (observational/mechanistic).
  • In rodents, central and peripheral humanin (and potent analogs) improved insulin sensitivity, increased glucose uptake, and suppressed hepatic glucose production; not demonstrated by administration in humans.
  • In cell and animal models, humanin is neuroprotective against amyloid-beta toxicity and protects endothelium and myocardium from ischemic/oxidative injury; human therapeutic benefit is unproven.
  • Higher endogenous humanin correlates with preserved coronary endothelial function and with better sperm quality in observational human studies (association only, not shown to be causal or to result from supplementation).
Safety

Adverse effects by system

Cardiovascular

No human data on effects of administered humanin. Endogenous higher levels are observationally associated with better coronary endothelial function, but this cannot be assumed to translate to safety or benefit from exogenous injection. Cardiovascular risk of exogenous dosing is unknown/uncharacterized.

Hepatic

No human hepatotoxicity data. Rodent studies show central humanin signaling suppresses hepatic glucose output; no direct hepatotoxic or hepatoprotective effect has been established in humans. Unknown.

Endocrine / HPTA

No evidence that humanin suppresses the hypothalamic-pituitary-gonadal axis. Humanin does interact with the GH/IGF-1 endocrine axis (inversely correlated in humans) and modulates insulin/glucose signaling in animals, so unquantified endocrine and glucose-metabolic effects are plausible; net human effect unknown.

Reproductive

No interventional human data. Endogenous seminal-plasma/sperm humanin correlates positively with sperm quality (observational); effects of exogenous administration on fertility, pregnancy, or a fetus are entirely unstudied and it should be avoided in pregnancy, lactation, and by those seeking conception.

Neuropsychiatric

No human psychiatric data. Preclinical work focuses on neuroprotection, not behavioral/psychiatric toxicity; effects in humans are unknown.

Renal

No human renal safety data. Clearance pathways and any nephrotoxic potential are uncharacterized.

Hematologic

No human hematologic data. As an unregulated injectable, contamination/endotoxin could provoke systemic inflammatory or febrile reactions, but no direct hematologic toxicity is characterized.

Dermatologic

No compound-specific data. Practical risk is generic to injectable use: injection-site pain, redness, bruising, and infection (including abscess) from non-sterile self-injection of unregulated product.

Recovery

HPTA suppression & recovery

Suppression: No evidence of direct HPTA (hypothalamic-pituitary-gonadal) suppression; not a steroid/SERM-class agent

Humanin is not an androgen, anabolic steroid, or SERM and there is no evidence it suppresses gonadal testosterone production, so SERM-based recovery frameworks do not apply. However, it does interact with the GH/IGF-1 and insulin/glucose endocrine axes in ways that are not quantified in humans. Any concern about hormonal or metabolic changes while using it should be evaluated with an endocrinologist and objective bloodwork rather than self-managed; do not add SERMs or other hormonal agents in an attempt to 'balance' it.

Bloodwork & vitals

Monitoring

Recommended labs & checks
Baseline and periodic fasting glucose and HbA1c (given metabolic/insulin-sensitizing signals in animal models)Comprehensive metabolic panel including liver enzymes (ALT/AST) and renal function (creatinine/eGFR) to detect organ effects given absent human safety dataCBC and inflammatory markers (e.g., CRP) if fever or systemic symptoms occur, to detect contamination/infection reactionsIGF-1 if there is any endocrine concern, interpreted by a clinician

Cadence: If someone uses it despite the lack of human data, a clinician should obtain baseline labs before use and repeat periodically (e.g., every 8-12 weeks) and promptly if symptoms arise; there is no validated monitoring schedule because the compound is not studied or approved in humans.

Warning signs — seek care
  • Injection-site redness, swelling, warmth, increasing pain, or pus (possible infection/abscess) — seek care
  • Fever, chills, rigors, malaise, or hypotension after injection (possible endotoxin/contamination or systemic reaction) — urgent care
  • Rash, hives, swelling, wheezing, or difficulty breathing (allergic/anaphylactic reaction) — emergency care
  • Symptomatic hypoglycemia (shakiness, sweating, confusion), especially if diabetic or on glucose-lowering drugs
  • Any new unexplained systemic symptoms — stop and consult a physician
Do not use if

Contraindications

  • Pregnancy, breastfeeding, and active attempts to conceive (no reproductive/developmental safety data)
  • Children and adolescents (no data)
  • Known or suspected active malignancy or history of cancer (humanin is anti-apoptotic and cytoprotective to stressed cells; theoretical concern that it could protect tumor cells from apoptosis — unstudied in humans, but a reason for caution)
  • Any use of an unregulated, non-pharmaceutical-grade injectable product of unverified identity, purity, or sterility
  • Known hypersensitivity to the peptide or reconstitution excipients
  • Use without physician oversight, especially in people with diabetes or on glucose-lowering therapy (potential additive/unpredictable effects on glucose metabolism)
Combinations

Interaction profile

  • ContraindicatedWith DNP: Additive cardiovascular strain

Check a specific combination in the interaction checker.

Harm reduction

Reducing harm & when to stop

  • Understand the core gap: there are no human safety trials, no established dose, and no approved product. Any use is self-experimentation with an unknown risk profile.
  • Do not use during pregnancy, breastfeeding, while trying to conceive, or in anyone under 18.
  • Discuss with a physician before use, especially if you have diabetes or take glucose-lowering medication, a history of cancer, or any chronic illness. Get baseline bloodwork (glucose/HbA1c, liver and kidney function, CBC) and repeat periodically.
  • Most realistic acute harms come from the injectable format, not the peptide's biology: use only individually packaged sterile needles/syringes, never share injection equipment, and use aseptic technique. Stop and seek care for injection-site infection (spreading redness, warmth, pus) or systemic reactions (fever, chills, low blood pressure).
  • Stop immediately and seek emergency care for signs of allergic reaction (hives, facial/throat swelling, wheezing, trouble breathing).
  • This monograph does not endorse use, dosing, stacking, or sourcing. Reported research doses are from animals and do not translate to a safe human dose. There is no 'optimal' regimen.
  • If your goal is the outcomes humanin is marketed for (longevity, metabolic health, neuroprotection), pursue evidence-based, clinician-supervised options instead of an unstudied injectable.
Evidence

Citations (9)

Every clinical claim above is tied to a primary source. Overall evidence grade D — this compound lacks adequate human data; claims rest on preclinical or mechanistic evidence.

  1. 01

    Humanin is a mitochondrial-derived peptide encoded within the 16S rRNA (MT-RNR2) region of mitochondrial DNA and acts as a retrograde cytoprotective signaling peptide.

    ReviewPMID 23402768 ↗

  2. 02

    Humanin protects cells from oxidative stress, serum starvation, hypoxia and other insults in vitro and improves cardiovascular and Alzheimer's disease models in vivo (animal/cell), via anti-apoptotic (BAX antagonism) and STAT3 mechanisms.

    ReviewPMID 23239898 ↗

  3. 03

    Circulating humanin levels decline with age in humans and mice, and humanin correlates inversely with GH/IGF-1 axis activity; GH or IGF-1 treatment reduced circulating humanin in human subjects and mice.

    CohortDOI 10.1111/acel.12243 ↗

  4. 04

    Central (intracerebroventricular) and peripheral humanin and potent analogs improve insulin sensitivity, increase glucose uptake, and suppress hepatic glucose production via hypothalamic STAT3 signaling in rodents; circulating humanin declines with age in humans and mice.

    PreclinicalHumanin: a novel central regulator of peripheral insulin action.DOI 10.1371/journal.pone.0006334 ↗

  5. 05

    Humanin and related small humanin-like peptides act as age-dependent insulin sensitizers and regulators of apoptosis and inflammation in cell and rodent models, with circulating levels decreasing with age.

    PreclinicalDOI 10.18632/aging.100943 ↗

  6. 06

    Lower plasma humanin is associated with coronary endothelial dysfunction in a cross-sectional study of 40 patients undergoing coronary angiography (observational association with endogenous levels, not administered peptide).

    CohortPMID 23220334 ↗

  7. 07

    Endogenous seminal-plasma and sperm humanin levels correlate positively with sperm concentration and motility in men undergoing fertility evaluation (observational).

    CohortDOI 10.1111/andr.12614 ↗

  8. 08

    Humanin produced by human efferocytic macrophages has pro-resolving/anti-inflammatory properties; preventive administration reduced leukocyte infiltration and pro-inflammatory cytokines in a mouse peritonitis model (human cell + mouse, mechanistic).

    PreclinicalDOI 10.1038/s41419-025-07909-1 ↗

  9. 09

    No human interventional trials, safety/toxicology studies, established dose, or regulatory approval exist for administering humanin or its analogs; human evidence is limited to observational studies of endogenous levels.

    ReviewPMID 23402768 ↗

Last reviewed 2026-07-06 · Verified against PubMed · Educational, not medical advice