Glutathione (liposomal)

Glutathione (GSH) is a small tripeptide made naturally in nearly every human cell from three amino acids: glutamate, cysteine, and glycine. It is the body's most abundant intracellular antioxidant and a central regulator of cellular "redox balance." "Liposomal" glutathione is ordinary glutathione wrapped inside phospholipid vesicles (liposomes) — a delivery strategy meant to shield the fragile molecule from being broken down in the gut and improve how much reaches the bloodstream. The molecule itself is identical to the glutathione your cells produce.

Education only. This page summarises published research on a cosmetic or dietary ingredient. It is not medical advice and makes no treatment claims; for a finished product, follow its label.

Also known as

GSH, L-glutathione reduced, reduced glutathione, gamma-L-glutamyl-L-cysteinylglycine, liposomal GSH, Setria glutathione (branded)

Class

Endogenous tripeptide antioxidant (gamma-glutamyl-cysteinyl-glycine); thiol-based redox cofactor. "Liposomal" denotes a phospholipid-encapsulated oral delivery format, not a different molecule.

How does Glutathione work?

Glutathione's reactive cysteine thiol (-SH) group neutralizes reactive oxygen and nitrogen species and serves as the electron donor for glutathione peroxidase enzymes, which convert hydrogen peroxide and lipid peroxides into water/alcohols. In doing so GSH is oxidized to GSSG (glutathione disulfide) and then recycled back to GSH by glutathione reductase using NADPH, forming a continuous redox buffer. It also detoxifies xenobiotics via conjugation (glutathione-S-transferases) and helps regenerate other antioxidants like vitamins C and E. The liposomal coating is intended to protect glutathione from gut/hepatic gamma-glutamyltransferase, which otherwise hydrolyzes most ingested glutathione before it is absorbed intact.

What has Glutathione been studied for?

• Raising whole-blood, erythrocyte, plasma and lymphocyte glutathione stores (depleted glutathione is associated with aging, oxidative stress and chronic disease)
• Markers of oxidative stress (e.g., 8-isoprostane, oxidized:reduced GSH ratio)
• Immune-function markers (natural killer cell cytotoxicity, lymphocyte proliferation) in small trials
• Skin tone/lightening (mainly via IV and high-dose oral routes — controversial, weak evidence, and a regulatory concern)
• Supporting detoxification and general antioxidant/'healthy aging' wellness positioning

What does the evidence show?

Mixed and still maturing for oral use. The core challenge: plain oral glutathione has very low systemic bioavailability (often cited below ~1%) because intestinal and hepatic gamma-glutamyltransferase degrade it; a classic study of a single 3 g oral dose showed no meaningful rise in plasma glutathione. Liposomal and other enhanced formulations were developed to overcome this and small human studies are encouraging but limited. A 1-month trial (Sinha et al., Eur J Clin Nutr 2018; n=12) reported liposomal glutathione raised whole-blood GSH ~40% and PBMC GSH ~100% at 2 weeks, lowered 8-isoprostane ~35%, and raised NK-cell cytotoxicity. A 6-month placebo-controlled RCT of NON-liposomal oral GSH (Richie et al., Eur J Nutr 2015; n=54) showed dose- and time-dependent ~30-35% rises in blood GSH stores that reversed after washout. Key caveats: sample sizes are small, many studies are industry-linked or use proprietary branded formulations, "blood glutathione went up" is a biomarker — not proof of a clinical outcome (disease prevention, longevity, skin appearance), and long-term outcome data are lacking. Skin-lightening claims in particular rest on weak, short-lived data.

What is known about the safety of Glutathione?

Oral glutathione is generally well tolerated in the short-term trials available (no serious adverse events reported in the 1- and 6-month studies above), though long-term safety of sustained high-dose supplementation is not well established. The serious safety signals are concentrated in INJECTABLE/IV use, which is a different product and route: the FDA has not approved any injectable glutathione for skin lightening, has warned compounders about contamination (e.g., endotoxin) risks, and adverse reactions reported in the literature include nausea, vomiting, chills, hypotension, breathing difficulty, possible bloodstream infection, and reports of liver/kidney/nervous-system toxicity and a case of anaphylaxis. Systemic skin-lightening use may also reduce protective melanin, theoretically raising UV/photodamage risk. People who are pregnant or breastfeeding, immunocompromised, on relevant medications, or with chronic conditions should consult a clinician before use; none of the injectable safety data should be used to self-administer anything.

What is the legal status of Glutathione?

In the US, oral glutathione is legal as a dietary supplement under DSHEA (1994) and certain branded forms (e.g., Setria glutathione) carry self-affirmed GRAS status for food/supplement use — so a liposomal oral sachet is a lawful consumer product. It is NOT an FDA-approved drug: it has not been reviewed by FDA for safety or efficacy to treat or prevent any disease, and supplement structure/function claims cannot be disease/treatment claims. INJECTABLE/IV glutathione is a different regulatory matter — there is no FDA-approved injectable glutathione for skin lightening, and FDA has issued warnings on compounded sterile glutathione. Glutathione is not a controlled substance and is not on the WADA prohibited list.

What is the half-life of Glutathione?

Very short in the bloodstream. After IV administration in humans, plasma glutathione half-life is roughly ~10-14 minutes (one study: 14.1 ± 9.2 min), and isotope-tracer studies put endogenous GSH turnover half-life around ~6-8 minutes — reflecting rapid plasma oxidation and recycling. This rapid turnover is why the focus is on sustaining intracellular glutathione stores over time rather than transient blood spikes.

Sources

1. Sinha R et al. Oral supplementation with liposomal glutathione elevates body stores of glutathione and markers of immune function. Eur J Clin Nutr. 2018;72(1):105-111.
2. Richie JP et al. Randomized controlled trial of oral glutathione supplementation on body stores of glutathione. Eur J Nutr. 2015;54(2):251-263.
3. Witschi A, Reddy S, Stofer B, Lauterburg BH. The systemic availability of oral glutathione. Eur J Clin Pharmacol. 1992;43(6):667-669.
4. Lu SC. Glutathione synthesis. Biochim Biophys Acta. 2013;1830(5):3143-3153. (review of GSH biosynthesis, redox cycle, GPx/GR mechanism)
5. FDA. Human Drug Compounding — concerns with compounded sterile glutathione injectables and warnings on glutathione for skin lightening.
6. Kyowa Hakko positions Setria glutathione for food applications with GRAS affirmation. FoodNavigator-USA, 2018.
7. Aebi S, Assereto R, Lauterburg BH. High-dose intravenous glutathione in man. Pharmacokinetics and effects on cyst(e)ine in plasma and urine. Eur J Clin Invest. 1991;21(1):103-110.
8. Exploring the Safety and Efficacy of Glutathione Supplementation for Skin Lightening: A Narrative Review. PMC.