This systematic review examined the molecular mechanisms by which glutathione, a key cellular antioxidant, influences skin aging and tissue regeneration through redox modulation and related signaling pathways. The review synthesized evidence demonstrating that glutathione depletion is associated with increased oxidative stress and impaired tissue repair, while glutathione restoration may modulate inflammatory and regenerative processes at the cellular level. This is a review article synthesizing existing literature across multiple evidence types (in vitro, animal models, and limited human clinical studies).