Glutathione is the most abundant antioxidant the human body makes, and unlike most of the research catalogue it has been through multiple randomized, placebo-controlled trials. Two of them are worth knowing in detail.<\/p>\n
For years the standard objection to oral glutathione was that it could not survive digestion. This trial tested that directly: 54 non-smoking adults took 250 mg or 1,000 mg of glutathione daily, or placebo, for six months. Glutathione levels rose in every compartment measured \u2014 blood, red cells, plasma, lymphocytes and buccal cells \u2014 in a dose- and time-dependent way, and the oxidised-to-reduced glutathione ratio fell, indicating lower oxidative stress. Levels returned to baseline after a one-month washout, which is exactly the behaviour expected of a genuine supplementation effect.<\/p>\n
Sixty healthy subjects took 500 mg daily or placebo for four weeks in a randomized, double-blind design. Melanin indices decreased at all six measured sites in the glutathione group, reaching statistical significance on the right side of the face and the sun-exposed left forearm \u2014 consistent with glutathione’s known role in shifting melanin synthesis. UV-spot imaging showed the same pattern.<\/p>\n
Glutathione sits at the centre of cellular redox chemistry: it neutralises reactive oxygen species, recycles other antioxidants, and its depletion is a feature of ageing and many disease models. The trials above are the reason it remains one of the most studied antioxidants in the literature.<\/p>\n
The 6-month randomized trial found blood glutathione rose 30-35% at the higher dose, with increases in every compartment measured, settling the older absorption debate for the studied formulation.<\/p>\n
In a 4-week double-blind trial of 60 subjects, oral glutathione reduced skin melanin indices versus placebo, significantly on the face and sun-exposed forearm, and was very well tolerated.<\/p>\n