Glutathione is a thiol-containing (-SH) antioxidant. It is the most potent antioxidant in human body and is the dominant antioxidant in the cell. It is present in water soluble form in the cytosol of the human body and other aqueous compartments. The intracellular glutathione content reaches the millimolar level and is therefore the highest concentration of antioxidant in the cell. Antioxidants are free radical scavengers, and modern medicine believes that free radicals are one of the leading causes of aging and disease. The most abundant and most important in antioxidant system of human cells is glutathione. Glutathione is the main force in scavenging free radicals and has been hailed as "master antioxidants" and "glutathione defense systems" by scientists. Glutathione
not only directly participates in scavenging free radicals, but also regulates external antioxidants such as vitamins C and E, and maintains their active (reduced) state. Therefore, glutathione has been added to health care products, skin care products and foods by more and more health care cosmetics companies.
Glutathione is a "recognized safe use substance" (GRAS) published by the US FDA. “GRAS” is determined by the food industry in accordance with relevant laws and regulations, published scientific evidence or long-term use history, and its prudent assessment of safety under specific conditions of use. In the GRAS statement of glutathione on the US FDA website, glutathione is recommended to be 0.004-0.667% in foods, beverages, cakes, and confectionery products.