Top 9 Best Glutathione Supplements (2026)
9 picks — ranked by our 50/50 methodology
- #1Best overall
Healthy Origins Setria L-Glutathione
Healthy Origins · Setria reduced L-glutathione (Kyowa, Japan), 500 mg · 150 veggie caps8.7/10SAC Product Score™SAC Product Score™ — how it breaks down- Form & absorption strategy30%7.5
- Dose vs studied range25%9.5
- Testing & label transparency20%8.5
- Value per day15%9.5
- Real-world fit10%9.0
A full 500 mg of the clinically-referenced Setria branded reduced glutathione, 150 capsules deep, at the lowest cost-per-day of any named-source pick. The best single-ingredient starting point — with the plain-form absorption caveat stated openly.
- Form
- Reduced L-glutathione — Setria branded (Kyowa, Japan)
- Dose
- 500 mg per capsule (label allows 1-2/day)
- Count
- 150 veggie capsules
- Absorption note
- Plain reduced form — debated oral absorption (see Richie 2015 vs Witschi 1992)
Pros- Genuine Setria branded reduced L-glutathione — the named, clinically-referenced raw material, stated on the listing
- Full 500 mg dose, squarely in the 250-1000 mg studied range; 150-count gives the lowest cost-per-day among named-source picks
- Single-ingredient, gluten-free, vegetarian; long-established family-owned brand
Cons- Oral absorption of plain reduced glutathione capsules is genuinely debated versus liposomal/S-acetyl forms
- No independent third-party seal (NSF/USP) called out on the listing
Our take — If you want a single-ingredient glutathione and you trust the slow-repletion reading of the evidence, this is the one to buy. It is the named Setria material at a full 500 mg, it is the cheapest named-source pick per day, and a 150-count bottle lets you run the multi-month protocol Richie 2015 suggests is what actually moves body stores. The honest catch is the form: this is plain reduced glutathione, the version whose absorption Witschi 1992 and Allen 2011 questioned. If that worries you, step up to a liposomal (#2, #3) or S-acetyl (#4) form — or consider NAC as the precursor route. For most buyers, though, Healthy Origins is the rational default.
- #2Best premium (liposomal)
Pure Encapsulations Liposomal Glutathione
Pure Encapsulations · Setria glutathione in a liposomal phospholipid complex, 375 mg · 60 softgels8.6/10SAC Product Score™SAC Product Score™ — how it breaks down- Form & absorption strategy30%9.5
- Dose vs studied range25%8.5
- Testing & label transparency20%9.0
- Value per day15%6.0
- Real-world fit10%8.5
Setria glutathione wrapped in a liposomal phospholipid complex — the cleanest practitioner-grade answer to the absorption objection. You pay for the delivery system, not for more milligrams.
- Form
- Liposomal softgel — phospholipid-encapsulated Setria glutathione
- Dose
- 375 mg Setria glutathione per softgel (label allows 1-2/day)
- Count
- 60 softgels
- Absorption note
- Liposomal delivery targets the GSH bioavailability problem (cf. Sinha 2018)
Pros- Liposomal phospholipid delivery directly targets the core bioavailability objection to oral glutathione
- Uses Setria branded glutathione; hypoallergenic, practitioner-channel brand reputation
- Free-from formulation philosophy — no unnecessary additives
Cons- Premium price per serving — among the most expensive picks here
- Contains soy (from the phospholipid/lecithin matrix); softgels are gelatin, so not vegan
Our take — This is the pick for the buyer who reads the absorption debate and decides to pay to sidestep it. The liposomal phospholipid shell is the most-studied delivery answer to glutathione's gut problem (Sinha 2018 showed liposomal GSH raised body stores), and Pure Encapsulations pairs it with the named Setria material and its practitioner-grade clean-label pedigree. The trade-offs are real: it is the priciest pick per serving, it carries 375 mg rather than a full 500 mg, and the soy-and-gelatin softgel rules out vegans. If you want the liposomal idea at a higher dose and lower price, Core Med Science (#3) is the value alternative; if you just want maximum cheap milligrams, a plain reduced capsule (#1, #5) is the other end of the spectrum.
- #3Best liposomal value
Core Med Science Liposomal Glutathione
Core Med Science · Setria glutathione in a phospholipid complex, 500 mg / 2 softgels · 60 softgels8.4/10SAC Product Score™SAC Product Score™ — how it breaks down- Form & absorption strategy30%9.0
- Dose vs studied range25%9.0
- Testing & label transparency20%8.0
- Value per day15%7.5
- Real-world fit10%7.0
A physician-developed liposomal that delivers a higher 500 mg Setria dose per serving — the higher-strength, better-value alternative to boutique liposomal brands.
- Form
- Liposomal softgel — phospholipid-encapsulated reduced Setria glutathione
- Dose
- 500 mg Setria glutathione per 2-softgel serving
- Count
- 60 softgels (30 servings)
- Absorption note
- Liposomal form + full 500 mg — the highest-dose liposomal here
Pros- Higher 500 mg Setria glutathione per serving in a liposomal phospholipid format
- Physician-developed; made in USA, non-GMO, free from dairy, egg, shellfish, wheat, tree nuts and fish
- Better cost-per-mg than most softgel liposomal competitors
Cons- Full dose requires 2 softgels, halving the bottle to a 30-day supply
- Manufacturer dosing asks you to wait 45-60 minutes before eating, which some users find inconvenient
Our take — Core Med Science is what you buy when you want the liposomal delivery advantage but balk at Pure Encapsulations' price-per-milligram. It carries the named Setria material at a full 500 mg per serving — the highest-dose liposomal on the list — in a clean, physician-developed, broad-allergen-free softgel. The catch is that the full dose is two softgels, so a 60-count bottle is really a 30-day supply, and the brand wants you to wait 45-60 minutes before eating. For the liposomal buyer chasing the best dose-per-dollar, it edges out #2; for the buyer who wants one softgel a day and the cleanest practitioner label, #2 still wins.
- #4Best S-acetyl form
Double Wood S-Acetyl L-Glutathione
Double Wood Supplements · S-Acetyl L-glutathione (acetylated), 100 mg · 60 capsules8.2/10SAC Product Score™SAC Product Score™ — how it breaks down- Form & absorption strategy30%8.7
- Dose vs studied range25%7.0
- Testing & label transparency20%8.0
- Value per day15%8.5
- Real-world fit10%9.0
The acetylated form — engineered with an acetyl group designed to survive the gut and be cleaved inside the cell. A distinct absorption mechanism from the reduced-form crowd, at a friendly price.
- Form
- S-Acetyl L-glutathione (acetylated)
- Dose
- 100 mg per capsule (label allows 1-2/day)
- Count
- 60 capsules
- Absorption note
- Acetyl group designed for gut stability + intracellular cleavage (mechanism, human outcome data thin)
Pros- S-acetyl (acetylated) form specifically addresses the oral-stability problem of plain glutathione
- Made in New York and tested for purity; non-GMO and gluten-free
- Single-ingredient formula; strongly reviewed established value brand
Cons- 100 mg per capsule is a lower elemental dose than the 500 mg reduced-form picks (the forms are not 1:1 comparable)
- S-acetyl raw material commands a higher price per mg than commodity reduced glutathione
Our take — S-acetyl glutathione is the third answer to the absorption question, distinct from both plain reduced and liposomal: the acetyl group is meant to shield the molecule through digestion and then be cleaved off inside your cells. Double Wood is the best-value S-acetyl pick — single-ingredient, purity-tested, from a brand with a strong review base. Be clear-eyed about two things: the dose is 100 mg, far below the 500 mg plain capsules (the form is the point, so don't read that as under-dosing), and the human outcome evidence for S-acetyl specifically is thinner than for plain or liposomal GSH — its case is mostly mechanistic. If the acetylated mechanism appeals to you, this is the one; if you want the better-evidenced delivery route, liposomal (#2, #3) has the human trial behind it.
- #5Best budget reduced
Jarrow Formulas Glutathione Reduced
Jarrow Formulas · Reduced (non-oxidized) L-glutathione, 500 mg · 60 veggie capsSAC Product Score™ — how it breaks down- Form & absorption strategy30%7.0
- Dose vs studied range25%9.5
- Testing & label transparency20%6.5
- Value per day15%9.0
- Real-world fit10%9.0
A clean, low-cost reduced-glutathione benchmark from a trusted brand at a full 500 mg in one capsule — the easy budget entry point. Honestly NOT labelled Setria, and we don't pretend otherwise.
- Form
- Reduced (non-oxidized) L-glutathione
- Dose
- 500 mg per capsule
- Count
- 60 veggie capsules
- Source note
- Brand product page does NOT state a Setria designation — no Setria claim made
Pros- Full 500 mg reduced (non-oxidized) glutathione in a single daily capsule
- Non-GMO, vegan, gluten-free; single-ingredient, very low sticker price
- Long-established, widely trusted supplement brand
Cons- Not labelled as Setria or any other branded glutathione (the brand's own product page does not mention Setria)
- Plain oral reduced glutathione has the most-debated absorption of the forms in this lineup
Our take — Jarrow is the honest budget pick: a full 500 mg of reduced glutathione, vegan and single-ingredient, from a brand people already trust, at the lowest sticker price on the list. The two things we will not dress up: its own product page does not claim Setria, so we don't either — you're buying clean generic reduced GSH, not the named branded material Healthy Origins (#1) carries. And it is the plain reduced form, the one with the most-debated absorption. If $14 to run a real 500 mg dose for two months and see how you respond is the experiment you want, this is the rational way to run it cheaply. For the named source, pay up to #1; for the absorption hedge, go liposomal (#2, #3); for the cheapest precursor route entirely, weigh NAC.
- #6Best detox stack
NOW Foods Glutathione 500 mg
NOW Foods · Reduced glutathione 500 mg + milk thistle + alpha lipoic acid · 60 veg caps7.9/10SAC Product Score™SAC Product Score™ — how it breaks down- Form & absorption strategy30%7.0
- Dose vs studied range25%9.0
- Testing & label transparency20%8.0
- Value per day15%7.5
- Real-world fit10%8.5
Bundles glutathione with milk thistle and alpha lipoic acid — a glutathione-recycling cofactor — for a liver-and-detox-oriented formula from a brand with strong in-house QC.
- Form
- Reduced L-glutathione + milk thistle extract 100 mg + alpha lipoic acid 50 mg
- Dose
- 500 mg glutathione per capsule
- Count
- 60 veg capsules
- Source note
- Not a Setria-branded source; multi-ingredient (harder to compare mg-for-mg)
Pros- Adds alpha lipoic acid and milk thistle — a coherent detox/antioxidant-recycling stack rather than glutathione alone
- NOW runs ISO/IEC-accredited in-house labs and is GMP quality-assured; vegan, non-GMO, kosher
- Reasonable price for a multi-ingredient formula
Cons- Not a single-ingredient product and not a branded (Setria) glutathione source — harder to compare mg-for-mg
- Plain oral reduced glutathione absorption remains debated; the added cofactors do not make it liposomal
Our take — NOW takes a different, defensible angle: instead of chasing absorption with an exotic delivery form, it surrounds plain 500 mg glutathione with cofactors that support the same job. Alpha lipoic acid helps regenerate oxidised glutathione back to its active form, and milk thistle (silymarin) is a classic liver-support botanical — so for the liver-and-detox buyer this is a coherent little stack, backed by NOW's genuinely strong in-house QC. The honest limits: it is still plain reduced glutathione (the cofactors don't solve the absorption debate), and being multi-ingredient makes it harder to compare milligram-for-milligram with the single-ingredient picks. Buy it for the liver-support stack concept; if you want glutathione alone, #1 or #5 are cleaner comparisons.
- #7Best sublingual liquid
Quicksilver Scientific Liposomal Glutathione
Quicksilver Scientific · Liquid nanoliposomal OPITAC glutathione (Kyowa), 100 mg · 1.7 fl oz7.8/10SAC Product Score™SAC Product Score™ — how it breaks down- Form & absorption strategy30%9.5
- Dose vs studied range25%7.0
- Testing & label transparency20%8.5
- Value per day15%5.0
- Real-world fit10%7.5
The most aggressive absorption play on the list — a liquid nanoliposomal you hold under the tongue, designed to bypass much of digestion before you swallow. Uses OPITAC (Kyowa), not Setria.
- Form
- Liquid nanoliposomal, sublingual — OPITAC glutathione (Kyowa) + sunflower phosphatidylcholine
- Dose
- 100 mg glutathione per 2-pump serving, held sublingually
- Count
- 1.7 fl oz (50 mL)
- Source note
- OPITAC branded (Kyowa's oral grade), NOT Setria; contains ethanol
Pros- Liquid nanoliposomal, sublingual delivery — intended to bypass much of digestive breakdown
- Uses OPITAC branded glutathione (Kyowa) with sunflower-derived phosphatidylcholine; gluten- and dairy-free
- Flexible pump dosing; well-regarded premium liposomal specialist brand
Cons- Highest cost-per-mg in the lineup and a small 50 mL bottle
- Contains ethanol; the sublingual hold-then-swallow ritual and taste are not for everyone
Our take — Quicksilver is the connoisseur's absorption play: a liquid nanoliposomal you hold under the tongue so some of the dose can absorb across the oral mucosa before the gut ever sees it. It uses OPITAC — Kyowa's oral-grade glutathione, a sibling to Setria but a different branded grade, which we flag because it's a real distinction — in a sunflower-phosphatidylcholine matrix. It is also the most expensive per milligram, comes in a small 50 mL bottle, carries ethanol, and asks you to tolerate a hold-then-swallow ritual. If you believe in sublingual delivery and want the most theoretically bioavailable route regardless of cost, this is it; for most buyers the softgel liposomals (#2, #3) deliver the same idea more cheaply and conveniently.
- #8Best bulk value
Nutricost Glutathione 500 mg
Nutricost · Reduced L-glutathione, 500 mg · 240 capsules7.6/10SAC Product Score™SAC Product Score™ — how it breaks down- Form & absorption strategy30%6.0
- Dose vs studied range25%9.5
- Testing & label transparency20%6.0
- Value per day15%9.5
- Real-world fit10%8.0
The bulk-value play: 240 capsules at a full 500 mg dose for the lowest cost-per-serving on the list — for high-volume daily users who want plain reduced glutathione and nothing else.
- Form
- Reduced L-glutathione
- Dose
- 500 mg per capsule
- Count
- 240 capsules
- Source note
- Generic (non-Setria) reduced glutathione; third-party tested per brand
Pros- 240-count at 500 mg/cap = the lowest cost-per-serving in this lineup
- Non-GMO, gluten-free, and third-party tested per the brand
- Simple single-ingredient formula
Cons- Generic (non-Setria) reduced glutathione with the debated oral-absorption caveat
- Budget brand without an NSF/USP certification seal on-pack
Our take — Nutricost wins on one axis decisively: cost-per-serving. A 240-count bottle at a full 500 mg works out to roughly a dime a day — by far the cheapest way to run a real glutathione dose long enough to matter (and Richie 2015 says months is what it takes). It is single-ingredient, third-party tested per the brand, and exactly what a high-volume daily user wants. The trade-offs put it at #8 rather than higher: it is generic reduced glutathione with no named branded source, no NSF/USP seal, and the same plain-form absorption caveat that hangs over every reduced capsule here. For the cost-optimiser who has already accepted the form debate, it's the value champion; for source transparency, #1 is worth the premium.
- #9Best liquid alternative
Designs for Health Liposomal Glutathione
Designs for Health · Liquid liposomal glutathione, 100 mg / mL · 1.7 fl oz (50 servings)7.5/10SAC Product Score™SAC Product Score™ — how it breaks down- Form & absorption strategy30%8.7
- Dose vs studied range25%6.5
- Testing & label transparency20%7.0
- Value per day15%7.5
- Real-world fit10%7.5
A practitioner-brand liquid liposomal alternative to Quicksilver — lemon-peppermint flavor, dropper/pump dosing, 50 servings per bottle for those who prefer liquids over softgels.
- Form
- Liquid liposomal — glutathione in a phospholipid matrix
- Dose
- 100 mg glutathione per 1 mL serving, held in mouth then swallowed
- Count
- 1.7 fl oz (50 servings)
- Source note
- Listing does not specify a branded (Setria/OPITAC) glutathione source
Pros- Liquid liposomal delivery bonded to phospholipids for enhanced absorption
- Practitioner-channel brand; non-GMO, gluten- and dairy-free, naturally flavored
- 50 servings per bottle at a flexible 100 mg/mL dose
Cons- Listing does not specify a branded (Setria/OPITAC) glutathione source
- 100 mg/serving is a lower elemental dose; liquid liposomals carry a price premium over capsules
Our take — Designs for Health rounds out the list as the practitioner-brand liquid liposomal for people who simply prefer a flavored dropper to a softgel or capsule. The liposomal delivery is the same bioavailability strategy as #2, #3 and #7, the lemon-peppermint format is pleasant, and 50 servings is a decent runway. It lands at #9 for two honest reasons: its listing doesn't name a branded glutathione source the way the Setria and OPITAC picks do, so you can verify less about the raw material, and at 100 mg per serving with a liquid-liposomal price premium it's neither the cheapest nor the best-documented option. If you want a liquid liposomal and like the flavor and format, it's a fine choice; if source transparency or dose-per-dollar matters more, look up the list.
▸ Affiliate disclosure: every Amazon link uses our Associates tag (superachieverclub-20). We earn a small commission at no cost to you; it funds independent reviews. We never accept payment to change a ranking.
Glutathione is the body's master antioxidant — a cysteine-containing tripeptide your cells make themselves to neutralise free radicals, recycle vitamins C and E, and run the liver's phase-II detox pathways. The marketing is irresistible: take the master antioxidant in a capsule and top up your tank. The science is messier, and we are going to be honest about it up front, because it changes which bottle you should buy. The single most important fact about oral glutathione is that the absorption of plain reduced GSH is genuinely debated. Glutathione is a peptide, and the gut is very good at breaking peptides down before they reach your bloodstream. In Witschi 1992 a single 3 g oral dose failed to raise plasma glutathione at all — "negligible" systemic availability. In Allen 2011, 500 mg a day for four weeks moved no oxidative-stress biomarkers. And yet Richie 2015 found that 250 mg and 1000 mg a day taken for six full months did raise the body's glutathione stores — slowly, cumulatively, not as a plasma spike. The honest reading is that plain oral GSH can probably replete you over months at a real dose, but it is not the instant antioxidant infusion the label implies. That debate is exactly why form is the first thing we rank. Liposomal encapsulation wraps glutathione in a phospholipid shell to shepherd it past digestion (Sinha 2018 showed liposomal GSH raised body stores and immune markers). S-acetyl glutathione bolts on an acetyl group engineered to survive the gut and be cleaved inside the cell. And clinically-referenced branded reduced GSH — Setria, from Kyowa in Japan — is the named raw material behind most of the better human work. These delivery strategies are not gimmicks; they are the supplement industry's direct response to "does this even get absorbed?" We bought nine of the most-credible glutathione products on Amazon, sorted them by absorption strategy first and dose second, and ranked them on form, dose versus the 250-1000 mg studied range, testing and label transparency, value per day, and real-world fit. One more honest note before the list: if your only goal is to raise glutathione cheaply, NAC (N-acetylcysteine) — the cysteine precursor your body uses to build its own glutathione — is the lower-cost alternative many clinicians reach for first, and it is worth weighing against everything below.
Want the best single-ingredient glutathione and don't want to overthink the form debate: get Healthy Origins Setria L-Glutathione (#1) — a full 500 mg of the clinically-referenced Setria branded reduced GSH, 150 capsules, the lowest cost-per-day of any named-source pick. Tight budget: Jarrow Formulas Glutathione Reduced (#5), a clean 500 mg reduced capsule at the lowest sticker price on the list (it is honestly NOT labelled Setria — that's the trade-off). Want the cleanest answer to the absorption objection and will pay practitioner prices: Pure Encapsulations Liposomal Glutathione (#2), Setria wrapped in a phospholipid complex. Want the same liposomal idea at a higher 500 mg dose and better value: Core Med Science (#3). Prefer the acetylated mechanism: Double Wood S-Acetyl L-Glutathione (#4). Most aggressive absorption play — a liquid you hold under the tongue: Quicksilver Scientific (#7), OPITAC (not Setria). And the honest fork in the road that sits over the whole category: plain oral glutathione's absorption is debated, the forms above exist because of that, and NAC is the cheaper precursor route if cost is your real constraint.
How we ranked these nine
Glutathione can't be ranked on milligrams alone, because the central question is whether those milligrams survive your gut. So form and absorption strategy carries the most weight: liposomal encapsulation, S-acetyl (acetylated) glutathione, and clinically-referenced branded reduced GSH (Setria) all exist specifically to answer the bioavailability objection that plain reduced glutathione faces — the objection raised by Witschi 1992 (a 3 g oral dose didn't raise plasma GSH) and Allen 2011 (500 mg/day moved no biomarkers), and only partly answered by Richie 2015 (250-1000 mg/day raised body stores over six months). Dose comes second, scored against that 250-1000 mg/day studied range — but with a crucial caveat: a 100 mg liposomal or S-acetyl dose is NOT directly comparable to a 500 mg plain capsule, because the form is doing the heavy lifting. Testing and label transparency act as the trust filter — is the source named (Setria/OPITAC), is the form honestly stated, is there third-party testing. Value per day is the tiebreaker within a form tier. Real-world fit — capsule vs softgel vs sublingual liquid, daily-dose convenience, additives — settles the rest.
- Form & absorption strategy30%
The defining axis. Liposomal (phospholipid-encapsulated), S-acetyl (acetylated to survive the gut), and named branded reduced GSH (Setria, Kyowa) all score higher than plain reduced glutathione, because plain oral GSH is the form with the most-debated absorption (Witschi 1992, Allen 2011). Sinha 2018 is the reason liposomal earns its premium. Plain reduced capsules can still rank well on dose + value, but they carry the absorption caveat openly.
- Dose vs studied range25%
Scored against the 250-1000 mg/day range used in the human repletion work (Richie 2015 used 250 mg and 1000 mg/day). A full 500 mg plain capsule sits squarely in range. Liposomal and S-acetyl picks at 100-375 mg score on dose with an explicit note: the lower elemental milligrams are offset by the delivery form, so they are not penalised the way an under-dosed plain capsule would be.
- Testing & label transparency20%
Is the raw material named and verifiable (Setria from Kyowa, OPITAC from Kyowa), is the form stated honestly, and is there any third-party / in-house testing called out? Single-ingredient formulas with a named branded source score highest. Generic 'reduced glutathione' with no source disclosure and no NSF/USP seal scores lower — not because it's fake, but because you can verify less.
- Value per day15%
Street price divided by a daily serving, within the product's form tier. Plain reduced capsules (especially high-count bottles) deliver the lowest cost-per-day; liposomal softgels and sublingual liquids cost several times more per serving. The tiebreaker between picks doing the same job — not a reason to pick a worse form.
- Real-world fit10%
Capsule, softgel, or sublingual liquid; one-a-day vs two; vegetarian vs gelatin; additives like soy lecithin or ethanol; pre-meal timing demands. The practical friction that decides whether you actually take it daily — which, given that repletion takes months (Richie 2015), is what determines whether it works at all.
The bottom line
If you just want to be told what to buy, start with the form question, because that is the question the whole category turns on. For the best single-ingredient glutathione, Healthy Origins Setria L-Glutathione (#1) is the rational default: the named, clinically-referenced Setria material at a full 500 mg, with the lowest cost-per-day of any named-source pick and a bottle big enough to run the months-long protocol the repletion evidence calls for. On the tightest budget, Jarrow Formulas Glutathione Reduced (#5) gives you a clean 500 mg reduced capsule at the lowest sticker price — with the honest caveat that it isn't labelled Setria. And for the deepest bulk value, Nutricost (#8) is about a dime a day.
If the absorption debate is what's stopping you — and it's a legitimate thing to be stopped by — the forms that exist to answer it are the liposomals and the acetylated version. Pure Encapsulations Liposomal Glutathione (#2) is the cleanest practitioner-grade liposomal (Setria in a phospholipid shell); Core Med Science (#3) is the same idea at a higher 500 mg dose for less money; Double Wood S-Acetyl L-Glutathione (#4) takes the distinct acetylated route; and Quicksilver Scientific (#7) is the most aggressive play of all, a sublingual liquid nanoliposomal using OPITAC. None of these is a gimmick — they are the supplement industry's direct response to a real scientific objection, and Sinha 2018 gives the liposomal route the most human support.
Two honest closing rules. First, set your expectations from the evidence, not the label: oral glutathione's bioavailability is genuinely debated — Witschi 1992 and Allen 2011 found little to nothing from plain GSH, while Richie 2015 found that 250-1000 mg a day raised body stores only over six patient months. So whatever you buy, judge it over months, not days, and don't expect a master-antioxidant infusion from a single capsule. Second, weigh the alternative: if your real constraint is cost and you mainly want to raise your own glutathione, NAC (N-acetylcysteine) — the cysteine precursor your body uses to build glutathione — is the cheaper route many clinicians try first, and it deserves a place in your decision even though it isn't on this list.
Every claim ranked above traces back to one of these
Peer-reviewed studies, meta-analyses, and clinical trials behind the picks. Click any citation to read the abstract on PubMed.
- [1]Richie 2015
Randomized controlled trial of oral glutathione supplementation on body stores of glutathione
In a 6-month randomized, placebo-controlled trial, oral glutathione at 250 mg/day and 1000 mg/day raised body stores of glutathione (in blood, erythrocytes, plasma and lymphocytes) versus placebo, with the high dose lowering an oxidative-stress marker. The key 'repletion is possible' trial — but it took months and a sustained dose, not a single-dose plasma spike.
- [2]Witschi 1992
The systemic availability of oral glutathione
In 7 healthy volunteers, a single 3 g oral dose of glutathione did not significantly raise plasma glutathione, cysteine or glutamate over the following 270 minutes — the authors concluded the systemic availability of oral glutathione is negligible in man. The origin of the oral-bioavailability debate and the reason plain reduced GSH carries an absorption caveat.
- [3]Allen 2011
Effects of oral glutathione supplementation on systemic oxidative stress biomarkers in human volunteers
A randomized, double-blind, placebo-controlled trial of oral glutathione (500 mg twice daily) over 4 weeks found no significant change in any biomarker of oxidative stress and no change in glutathione status. The shorter-term counterpoint to Richie 2015 — and direct evidence that plain oral GSH does not reliably move biomarkers in weeks.
- [4]Sinha 2018
Oral supplementation with liposomal glutathione elevates body stores of glutathione and markers of immune function
In healthy adults, oral LIPOSOMAL glutathione raised body stores of glutathione and improved markers of immune function (natural-killer and T-cell activity) versus baseline. The human trial that justifies the liposomal premium — encapsulation is the delivery strategy that exists precisely because plain oral GSH is doubted.
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