Glutathione Dosage: What the Trials Actually Used (250-1000mg/day)
Educational summary — not medical advice. Glutathione has no established RDA or upper limit at any dose. This statement has not been evaluated by the FDA. This product is not intended to diagnose, treat, cure, or prevent any disease.
The honest answer
Richie 2015's body-stores trial used 250mg/day and 1000mg/day for 6 months — both worked, dose-dependently. The skin-lightening trials clustered lower: 500mg/day for 4 weeks (Arjinpathana) and 250mg/day for 12 weeks (Weschawalit). Setria-brand doses (200mg-1g/day) come from exercise trials paired with L-citrulline — not skin or absorption evidence. There's no RDA or upper limit because glutathione isn't an essential nutrient your diet needs to supply.
The dose depends on which claim you're chasing
Glutathione's trial doses split cleanly by which of the three central claims a study actually measured, and the honest approach is matching the dose to the outcome you actually want — not defaulting to the biggest number on the shelf. For raising body glutathione stores, Richie 2015 (n=54, 6 months) tested 250mg/day and 1000mg/day head to head and found both raised blood, erythrocyte, plasma, lymphocyte, and buccal-cell glutathione in a dose-dependent way — the high-dose group showed larger gains, but neither dose was tested beyond 1000mg/day, so there's no trial evidence for going higher. For skin lightening, the doses run lower and the trial durations shorter: Arjinpathana 2012 (n=60, 4 weeks) used 500mg/day in divided doses and reached significance at 2 of several measured sites; Weschawalit 2017 deliberately tested a lower 250mg/day dose over 12 weeks and still found a positive trend. Handog 2016's oral lozenge trial does not disclose its dose in the indexed abstract at all — that's an unknown, not a number to guess at, and it's a further reason to weight that open-label, single-arm, uncontrolled trial lightly. Setria-brand (Kyowa Hakko) reduced glutathione shows up in human trials at 200mg-1g/day, but every located trial paired it with L-citrulline for exercise and vascular endpoints (nitric oxide markers, endothelial function, lean mass) — never tested alone for absorption or skin outcomes, so don't borrow those doses for a skin or general-antioxidant claim. S-acetyl-glutathione retail products commonly sell at much lower doses (100mg is typical) on the premise that acetylation makes it more bioavailable per mg — a mechanistic claim, not a verified human head-to-head equivalence in this pack.
| Use case | Dose studied | Result |
|---|---|---|
| Body-stores, low dose | 250 mg/day, 6 months | Whole blood +17%, erythrocytes +29% (p<0.05) — Richie 2015 |
| Body-stores, high dose | 1000 mg/day, 6 months | Erythrocytes/plasma/lymphocytes +30-35%, buccal cells +260% (p<0.05) — Richie 2015 |
| Skin lightening, higher dose | 500 mg/day (divided), 4 weeks | Melanin index reduced significantly at 2 of several sites — Arjinpathana 2012, authors' own hedge: "a small number of subjects" |
| Skin lightening, lower dose | 250 mg/day, 12 weeks | Melanin index/UV spots trended lower vs placebo; per-group n not disclosed — Weschawalit 2017 |
| Skin lightening, uncontrolled | Dose not disclosed, 8 weeks | Melanin index decreased from baseline — Handog 2016, open-label, single-arm, NO control group |
Dose checker: how much glutathione are you actually taking?
Enter the actual reduced-glutathione milligrams per serving from your label (look for "Glutathione ___ mg" on the Supplement Facts panel — not a wheat-germ or extract weight) and how many servings you take per day.
How to think about which dose to pick
- 250mg/day is the safest default reference point — it's a dose tested in both the body-stores trial (Richie) and one skin trial (Weschawalit), over the longest durations in this evidence pack (6 and 12 months/weeks respectively).
- 500mg/day is the most-cited skin-lightening dose (Arjinpathana), but the trial ran only 4 weeks and reached significance at just 2 of several measured sites — read the authors' own hedge, not just the headline finding.
- 1000mg/day is the upper end tested for body stores, not a ceiling proven safe indefinitely — Richie's trial ran 6 months with no reported red flags, but no trial in this pack went higher or longer.
- Don't borrow Setria's 200mg-1g exercise doses for a skin or absorption claim. Those trials always paired Setria with L-citrulline and measured exercise/vascular outcomes, not skin or plasma glutathione alone.
- Pregnant or breastfeeding? There is no data at all for glutathione supplementation in this population — check with a clinician, because of the total absence of data, not a specific toxicity signal.
Picks by dose
Full ranking, including why liposomal and S-acetyl aren't ranked on absorption superiority, is on best glutathione.
Discloses 500 mg actual reduced glutathione per serving.
As an Amazon Associate we earn from qualifying purchases. Of 6 products tracked; ranked by disclosed actual mg, never commissions.
Frequently asked questions
How much glutathione should I take per day?
Richie 2015 used 250 and 1000mg/day for body stores (6 months, both effective). Skin trials used 500mg/day (4wk) or 250mg/day (12wk). No RDA or upper limit exists.
Is a higher glutathione dose better?
For body stores, 1000mg outperformed 250mg in Richie 2015 — but no trial tested above 1000mg. For skin, a lower 250mg dose (Weschawalit) still showed a positive trend.
Does the Setria 200mg-1g dose apply to skin or absorption?
No. Every Setria human trial paired it with L-citrulline for exercise/vascular endpoints — never tested alone for skin or absorption.
Is there a glutathione RDA or upper limit?
No. Not an essential nutrient in the deficiency sense, so no RDA or official UL exists. The trial doses are reference points, not regulatory limits.
Related
- Glutathione: what it is & who it's for
- Best glutathione — ranked by actual mg, then cost per mg
- Glutathione for liver & oxidative stress
- Absorption & skin-whitening, in full
Sources
- Richie JP, et al. "Randomized controlled trial of oral glutathione supplementation on body stores of glutathione." Eur J Nutr. 2015. PMID: 24791752 (250 & 1000 mg/day).
- Arjinpathana N, Asawanonda P. "Glutathione as an oral whitening agent." J Dermatolog Treat. 2012. PMID: 20524875 (500 mg/day).
- Weschawalit S, et al. "Glutathione and its antiaging and antimelanogenic effects." Clin Cosmet Investig Dermatol. 2017. PMID: 28490897 (250 mg/day).
- Handog EB, et al. "An open-label, single-arm trial of the safety and efficacy of a novel preparation of glutathione as a skin-lightening agent." Int J Dermatol. 2016. PMID: 26148180 (dose not disclosed).
- Full product dataset: /glutathione/cost-by-brand.json (CC BY 4.0).