Glutathione is a key component of the antioxidant system which protects the body from free radicals at the cellular level. Within the cells, it is present in two forms: reduced and oxidized glutathione; a healthy cell has significantly higher levels of the reduced form. Reduced glutathione is involved in the synthesis and repair of DNA, and enhances the antioxidant activity of vitamin C, the transport of amino acids, and the detoxification of harmful compounds. It is especially important for healthy liver function. In addition, an intracellular abundance of reduced glutathione, as compared to oxidized glutathione, helps ensure normal cell proliferation.