Glutathione

What Is Glutathione?

Glutathione (GSH) is a tripeptide composed of three amino acids: L-glutamate, L-cysteine, and glycine — synthesised in every cell of the body, with the highest concentrations in the liver. It is the primary intracellular antioxidant, involved in neutralising reactive oxygen species (free radicals), regenerating vitamins C and E, detoxifying xenobiotics and heavy metals, and supporting immune function. The body's capacity to synthesise and maintain glutathione is considered a key indicator of cellular health and oxidative stress status.

Specification & Form

How It's Sourced

YNP Ingredients sources Glutathione from certified manufacturers in China, supplied with FSSAI-compliant documentation.

Applications

• Antioxidant supplement formulations
• Skin health and brightening supplements (significant market in India, Southeast Asia, and East Asia)
• Liver support and detoxification products
• General wellness and longevity formulations
• Combined antioxidant blends (alongside Vitamin C, Vitamin E, and coenzyme Q10)

Industries Served

Nutraceuticals/Dietary Supplements · Functional Food/Beverage

The Oral Bioavailability Debate — What the Evidence Shows

This is the most clinically important issue for formulators positioning glutathione as an oral supplement, and the Source-of-Truth Policy requires presenting it accurately:

Against adequate oral absorption: Witschi et al. (1992) demonstrated in a controlled human study that a single 3 g oral dose of glutathione did not significantly increase plasma glutathione levels in healthy volunteers, suggesting that glutathione is substantially degraded in the gastrointestinal tract before absorption. This remains the most-cited evidence against simple oral glutathione supplementation.

For improved oral absorption (with modification): Richie et al. (2015) found that 500 mg/day oral reduced glutathione over 6 months did produce measurable increases in glutathione concentrations in blood, buccal cells, and lymphocytes in healthy adults — suggesting some absorption does occur with repeated lower-dose supplementation. Sinha et al. (2018) demonstrated that liposomal glutathione — encapsulating GSH in phospholipid vesicles — produced better bioavailability than conventional oral forms.

Conclusion for formulators: The evidence does not support simple oral glutathione as equivalent in bioavailability to intracellular GSH. Claims should reflect what has been studied — "provides glutathione as an antioxidant" or "supports antioxidant status" with appropriate qualification — rather than implying direct intracellular delivery at the scale of endogenous GSH.

Buyer Checklist

• Confirmed intended application and appropriate claim language given the oral bioavailability context
• If formulating a liposomal product, confirmed the encapsulation technology is compatible with the glutathione ingredient sourced here
• COA confirming assay/purity (reduced glutathione %)
• FSSAI-compliant documentation confirmed
• 25 kg pack size and MOQ confirmed

Common Mistakes

Claiming oral glutathione "restores intracellular GSH levels" without qualification. The evidence does not support this claim for conventional oral dosage forms. Qualified language ("supports antioxidant status," "provides reduced glutathione") is more defensible.

Conflating skin-whitening injections with oral supplementation. IV glutathione injections for skin lightening are a distinct application with a separate regulatory status — FSSAI and WHO have both issued cautions about unlicensed IV glutathione for skin lightening. Oral supplement positioning is a separate, more straightforward regulatory context.