Glutathione
GSH / gamma-Glutamylcysteinylglycine / The master antioxidant
The body's master antioxidant — a tripeptide naturally produced in every cell, responsible for neutralizing free radicals, supporting detoxification, and regulating immune function. Levels decline with age and under chronic stress. Among the most researched compounds in this database with genuine human clinical trial data across multiple conditions. IV glutathione is widely used in longevity and integrative medicine clinics.
Note: Glutathione is a tripeptide antioxidant — it is technically a peptide (three amino acids: glutamate, cysteine, and glycine) and is naturally produced in every cell in the human body.
Mechanism of action
Tripeptide of glutamate, cysteine, and glycine. Functions as the primary intracellular antioxidant — directly neutralizing reactive oxygen species. Essential cofactor for glutathione peroxidase enzymes. Central to Phase II liver detoxification — conjugates toxins for excretion. Regenerates vitamins C and E from their oxidized forms. Regulates T-cell function and immune signaling. Maintains protein sulfhydryl groups. The cysteine residue is the active antioxidant component — cysteine availability is typically the rate-limiting factor in glutathione synthesis.
Effects in the body
Glutathione is one of the few compounds in this database where the evidence base is both broad and genuinely strong. Multiple human RCTs document benefits in oxidative stress reduction, liver protection, skin lightening (melanin synthesis inhibition), Parkinson's disease symptom reduction, and immune function in HIV. IV administration produces significantly higher bioavailability than oral — oral glutathione is substantially broken down in the GI tract before absorption. Liposomal oral and sublingual/nasal formulations improve oral bioavailability.
Pros & cons (from the literature)
- Naturally produced by every human cell — among the safest compounds in this database
- Multiple human RCTs across diverse indications
- Central role in detoxification and antioxidant defense
- Skin brightening effects documented in human trials
- Parkinson's symptom reduction in preliminary trials
- IV administration widely available through longevity clinics
- Synergistic with NAD+, vitamin C, and alpha lipoic acid
- Oral bioavailability poor — most oral glutathione is broken down before absorption
- IV administration requires clinical setting
- Liposomal and nasal formulations improve bioavailability but cost more
- Skin lightening effect may be unwanted by some researchers
- Suppresses melanin — theoretical interaction with tanning peptides (MT-1, MT-2) if researched simultaneously
- High doses may paradoxically impair some immune functions
Protocol summary (from published research)
Dosing ranges reproduced from published research literature. Not a prescription, not medical advice.
FDA & regulatory status
Evidence base
Multiple human RCTs published. Weschawalit et al. 2017 skin trial published. Parkinson's pilot trials by Sechi et al. HIV immune function data documented. Cochrane review on liver protection available. Evidence tier 4 — strongest evidence base of any compound added in this batch.
Primary research sources
Peer-reviewed literature referenced throughout this profile is drawn from PubMed, Cell Metabolism, and clinical trial registries cited in the evidence base above.