The science suggests that glutathione helps inhibit tyrosinase, an enzyme involved in melanin production, which can contribute to a more even skin tone over time
Porcu M, Urbano MR, Verri WA Jr, Barbosa DS, Baracat M, Vargas HO, et al
The science on NAC is clear
14 (1), 8996 (2017) Snezhkina, A.V., Kudryavtseva, A.V., Kardymon, O.L., Savvateeva, M.V., Melnikova, N.V., Krasnov, G.S., et al.: ROS generation and antioxidant defense systems in normal and malignant cells
Laboratory research record on Glow | GHK-CU, TB-500, BPC-157 Blend [PMID: 29998800] PubMed laboratory record discussing Glow | GHK-CU, TB-500, BPC-157 Blend in a research context