Glutathione (GSH)

Glutathione (γ-L-glutamyl-L-cysteinyl-glycine) is the most important intracellular antioxidant and the liver's main detoxification cofactor (phase II conjugation). It takes part in the protection against oxidative and nitrosative stress, regenerates vitamins C and E and is essential for immune function. A low glutathione level is frequently described in chronic conditions, burnout, autoimmunity and heavy metal exposure. Measured directly as the intracellular GSH/GSSG ratio in whole blood.

How glutathione works

Every cell makes glutathione from the amino acids glutamate, cysteine and glycine; cysteine is usually the limiting building block and comes partly from methionine metabolism. In its reduced form (GSH), glutathione donates electrons and thereby neutralises reactive oxygen compounds; this produces the oxidised form (GSSG). The enzyme glutathione reductase regenerates GSH with the help of vitamin B2 and NADPH. The GSH to GSSG ratio therefore shows how much oxidative stress the cell is currently under. In the liver, glutathione binds pollutants and drug residues so that they can be excreted via bile and urine; the glutathione peroxidases additionally need selenium.

Low glutathione – what happens in the body?

With little GSH or a low GSH/GSSG ratio, reactive oxygen and nitrogen compounds are neutralised more slowly: fats in cell membranes, proteins and genetic material are oxidised more, and the mitochondria work less efficiently. The liver binds pollutants more slowly, and immune cells, especially T cells, multiply less well. Causes are high consumption – for example with inflammation, infections, alcohol or pollutant exposure – or low production when cysteine, glycine, selenium or vitamin B2 are scarce.

High glutathione – what does it mean?

A high GSH value with a favourable GSH/GSSG ratio shows a well-stocked antioxidant reserve. A raised GSSG share, by contrast, shows that a lot of glutathione is currently being used up – a sign of acute oxidative stress.

The interpretation is given in your report.