Master antioxidant
Glutathione
Also searched as Glutathione.
You want it replete: abundant glutathione is frontline protection against toxic and oxidative injury.
In depth
Glutathione — the body's main built-in antioxidant, made inside cells throughout the body (liver, eyes, lungs, immune cells and more) to neutralize harmful oxidants and help clear toxins.
What drives it
Antioxidant defense increases it.
Nrf2/GCLc study 2013, Hepatol Mon — Nrf2 binds the antioxidant-response element in the glutamate-cysteine ligase (GCLc, rate-limiting for GSH) promoter, inducing glutathione synthesis. PMID 23967023. Sources: Redox Biol 2018 doi 10.1016/j.redox.2018.06.006; PMC3166574; PMC6259123; PMC3677633. NRF2 acts by binding the antioxidant response element as a heterodimer with small MAF proteins — it raises capacity to make glutathione, it does not itself supply cysteine, so substrate availability remains limiting. The caveat that must travel with every NRF2 claim: NRF2 activation is not uniformly good. Tumors carry activating NRF2 mutations, and NRF2 cancer target genes are functionally linked to metabolic, proliferative and chemoresistance advantages; glutathione and thioredoxin are described as essential for cancer initiation and progression (Redox Biol 2018, doi 10.1016/j.redox.2018.06.006). In SDHB-deficient tumor cells, NRF2-guided glutathione synthesis supports survival and proliferation, and NRF2 blockade caused severe cytotoxicity — the NRF2 inhibitor brusatol is being developed as a therapy. doi 10.1016/j.redox.2018.06.006 · PMID 23967023 · PMC3166574
Sulfur clearance route increases it.
Cysteine is the rate-limiting amino acid for glutathione synthesis. This is why glutathione status is not simply a matter of taking glutathione. Carried by the intermediary-metabolism and clinical reviews. doi 10.1016/j.molmet.2023.101755 · PMC9967593
Reducing power supply increases it.
Antioxidant capacity is a metabolic output, not a stock. Glutathione does not stay reduced by itself - regenerating it costs NADPH, and NADPH comes from glucose through this pathway. Carried by the intermediary-metabolism and clinical reviews. doi 10.1016/j.molmet.2023.101755 · PMC9967593
Selenium proteins increases it.
Selenium has NO general antioxidant action of its own - it works only by being built into these enzymes. Glutathione peroxidase is a selenoprotein. Carried by the intermediary-metabolism, micronutrient and clinical reviews. doi 10.3390/nu18132141 · PMC9967593
Glutamine status increases it.
A glutathione precursor via glutamate. Carried by the intermediary-metabolism, micronutrient and redox reviews. doi 10.3390/nu18132141 · PMC9967593
Glycine calming increases it.
One of the three glutathione amino acids. Carried by the intermediary-metabolism, micronutrient and redox reviews. doi 10.3390/nu18132141 · PMC9967593
What it drives
It increases Liver.
APAP-hepatotoxicity review — hepatic glutathione scavenges the reactive metabolite NAPQI; GSH depletion initiates hepatocyte injury and N-acetylcysteine (a GSH precursor) is the clinical antidote. PMC6800176
It increases Hearing.
Mitochondrial antioxidants, modulators of mitochondrial function, calcium channel blockers, and mtDNA mutations that affect mitochondrial activity in the auditory system have emerged as critical factors in hearing protection. The reviewers state their own gap: there is still a lack of information on the underlying mechanisms of redox homeostasis and molecular redox networks in hair cells - so these are protective-target candidates, not demonstrated interventions. The clinical fact that makes protection the only strategy: mammalian cochlear hair cells do not regenerate, which is why SNHL is described as the most common type of permanent hearing impairment. doi 10.1016/j.mito.2025.102063 · PMC10102650
It increases Micronutrient status.
Micronutrient status is assembled from supplement-trial indices; none of the papers cited studied micronutrient status itself. Sources: PMC13074595; doi 10.3390/ijms26146740; doi 10.1139/H07-174. doi 10.3390/ijms26146740 · PMC13074595
It increases Recovery.
Recovery is a cell-interaction problem, not a rest period: satellite cells, inflammatory cells (neutrophils, macrophages, T lymphocytes, mast cells), vascular cells (pericytes, endothelial cells) and stromal cells interact with each other within the extracellular matrix. The dynamics of these intercellular interactions determine the effectiveness and time course of recovery. A measurable finding with a startling time course: blood markers of oxidative stress - depletion of reduced glutathione - can persist for longer than a month following an ultra-endurance running event. Athletes with chronic overtraining syndrome show raised malondialdehyde adducts at baseline and reduced plasma antioxidant capacity. And a species caution the reviewers make themselves: it is important not to draw direct comparisons between animal studies and recovery of exercise-induced muscle inflammation in humans. doi 10.1152/japplphysiol.00971.2016 · PMID 33420603 · PMC10854791
It increases Resists infection.
The headline on this pathway is a disappointment and it must stay there: the lack of effect of prophylactic vitamin C supplementation on the incidence of common cold in normal populations throws doubt on the utility of this wide practice. Regular supplementation decreases cold duration by 8 percent (3-12) and severity by 15 percent (CI 9-21) - but does not reduce how often you get one. With one striking exception that defines WHO it works for: a subgroup of six studies of marathon runners, skiers, and soldiers exposed to significant cold AND/OR physical stress experienced, on average, 50 percent reduction in common cold incidence. Extreme physical stress is the condition under which it prevents. PMC10712193
It increases Male fertility.
The finding that unifies all three nodes is that the same androgen does opposite things in different tissues: testosterone acts directly, and indirectly through intracellular conversion to dihydrotestosterone by 5-alpha reductase, as in prostate cells, and separately through estrogen effect when converted to estradiol by aromatase. Raise testosterone and you also raise DHT and estradiol - which is why the same intervention supports male hormonal health and can enlarge the prostate. And the clinical data shows both arms at once: in 183 men over 50 with BPH, testosterone was significantly lower in patients with severe LUTS (285.94 ng/dL) than mild (544.09 ng/dL) - so low testosterone tracks with worse urinary symptoms, while DHT drives the gland. That is not a contradiction to resolve, it is two different molecules. Bidirectionality is explicit: the relationship between hypogonadism and metabolic disorders is bidirectional, and a vicious circle between the two components has been documented. PMC6669361
It increases Liver clearance.
10.3389/fnint.2015.00061 — https://www.merckmanuals.com/professional/injuries-poisoning/poisoning/acetaminophen-poisoning — The aging outcome lists the thirteen hallmarks themselves, each mapped to its pathway and labeled with its hallmark number. (from the reviews of this outcome). doi 10.3389/fnint.2015.00061
It increases Vision.
Why the retina is the most oxidatively stressed tissue in the body, stated directly: the retina is highly susceptible to oxidative damage due to its elevated oxygen consumption, abundant polyunsaturated fatty acids, and continuous exposure to light. Three risk factors that cannot be separated from its function. And the aging failure is specific and double: in the elderly both the mitophagic process and Nrf2 activation ARE impaired, thus causing retinal cell death. The carotenoid case is unusually mechanical: lutein and zeaxanthin ARE selectively taken up by the RPE, preferentially accumulated in the human macula, and transferred to photoreceptors - a targeted delivery route, not a general antioxidant claim. The Eye Disease Case-Control Study found high plasma levels of lutein and zeaxanthin associated with reduced risk of neovascular AMD. By contrast the reviewers say the relationships between dietary and serum levels of the antioxidant vitamins and age-related macular disease ARE less clear - with alpha-tocopherol the exception, convincingly demonstrated. Lipofuscin is itself a photoreactive substance - the waste product becomes a new damage source. doi 10.3390/antiox14101251 · PMID 11033038 · PMC12026614
It increases Wound healing.
The one measured finding among them is the periodontal-anemia link: a meta-analysis of sixteen studies on hemoglobin and iron metabolism in periodontitis, whose authors call the association still controversial and ask for larger cohorts. doi 10.1152/japplphysiol.00971.2016 · PMC7005133
It increases Gasotransmitter signaling.
H2S is generated from cysteine metabolism, sharing substrate with glutathione synthesis. Carried by the vascular and erectile physiology reviews. doi 10.21037/tau-2025-419 · PMC11988752
It increases Female fertility.
The central finding is that reactive oxygen species ARE required, not merely harmful: ROS in the ovary regulate ovarian steroid hormone production, follicle synthesis, maturation, ovulation, and tubal function. ROS and antioxidant levels regulate the microenvironment of the follicular fluid, which determines which follicle becomes dominant. ROS can trigger ovulation in mature GRAAF follicles, and any change in this ROS level can disrupt ovulation. So an antioxidant claim here cuts both ways - the requirement is redox homeostasis, not suppression. Excess oxidative stress damages the oocyte through mitochondrial dysfunction, follicular atresia, meiotic errors, DNA damage and telomere shortening; too little disrupts the ovulatory trigger itself. Scale: infertility affects approximately 10-15 percent of couples, with nearly half the cases attributed to female reproductive dysfunction. doi 10.3390/antiox12081490 · PMID 40712896 · PMC10666387
It increases Alcohol recovery.
10.3390/antiox10030364 — Drawn from reviews of neighboring outcomes rather than from studies of this outcome itself, which is weaker evidence, and the map marks it so. Verbatim: “Although combination therapy with prednisolone plus N-acetylcysteine increased 1-month survival among patients with severe acute alcoholic hepatitis, 6-month survival, the primary outcome, was not improved”. doi 10.3390/antiox10030364
It increases Supports airflow & lung function.
10.1186/s12931-020-1292-7 — Drawn from reviews of neighboring outcomes rather than from studies of this outcome itself, which is weaker evidence, and the map marks it so. doi 10.1186/s12931-020-1292-7
It reduces Supports lens clarity.
The proteins are protected and maintained in a reduced state with intrinsic antioxidants, such as glutathione (GSH), and redox-regulating enzyme systems, such as thioltransferase to maintain the…. PMC12189886
Blends that modulate it
Each blend page names this pathway and carries the study behind its claim.
See it on the map
Open the causal map to follow this pathway upstream and downstream, arrow by arrow, each with its study.