The pathway of glutathione oxidation-reduction. Source: The Robert Edwards Group.
Glutathione is a potent antioxidant that is naturally found in the skin. Unfortunately, according to The Prescription for Nutritional Healing, glutathione levels decrease 30-35% over the course of one’s lifetime with normal aging. In the body, glutathione acts as an antioxidant and detoxifier, most prominently in the liver, kidneys, and bone marrow.
In the skin, glutathione has been found to be more prevalent in the epidermis (outermost layer of skin) than the dermis. Together with vitamin C, glutathione is actually one of the major water-soluble antioxidant metabolites naturally found in the cell, according to Dr. Rafaela M. Quiroga in the textbook Cosmetic Dermatology. Glutathione protects cells after an enzyme known as glutathione peroxidase catalyzes the reaction between glutathione and hydrogen peroxide, ultimately forming water and oxidized glutathione, which is a stable compound.
It has also been well-established that glutathione levels decrease with exposure to UV light, according to The Journal of Investigative Dermatology (amongst other sources), in a manner that is similar to other antioxidants, like vitamin C or vitamin E. With continued exposure to UV light, the lower levels of glutathione increase the skin’s susceptibility to UV-induced damage, as findings reported in Photochemistry and Photobiology suggest.
To supplement levels of glutathione, N-acetylcysteine is often taken as an oral supplement, which is converted to glutathione in the body. While typical dosages of N-acetylcysteine range from 250-1500 mg/day and no toxic level has been established as of yet by the FDA, check with your doctor to be safe, as side effects have been reported in some individuals.
Glutathione has also been shown to be an effective antioxidant when topically applied to the skin. However, the effects of glutathione can be enhanced by either lipoic acid or vitamin C, because these ingredients effectively recycle the antioxidant power of glutathione. For this reason, glutathione is best used in formulations with lipoic acid and/or vitamin C. One excellent formulation is Perricone Pore Refining Concealer ($35.00, Sephora.com), with glutathione and lipoic acid. Another is Philosophy When the Hope is Not Enough Facial Serum ($38.00, Sephora.com), with glutathione and vitamin C.
Overall, glutathione is a promising antioxidant. Because its levels naturally decrease with age, leaving the skin more susceptible to UV-induced damage, I think it seems like a good idea to use a cream or serum with glutathione. As always, consult with your derm if you have any concerns! 🙂