GRSUltra brings you the clinically-proven nutrients that guarantee your body will be flooded with glutathione, which is 5,000 times stronger than any other antioxidant.
For basic information on the active ingredients see these links from WebMD.com:
https://www.webmd.com/a-to-z-guides/supplement-guide-selenium#1
https://www.webmd.com/vitamins/ai/ingredientmono-1018/n-acetyl-cysteine
Scientific Research and Evidence:
Selenium:
Rayman, M. P. (2000). The importance of selenium to human health. The Lancet, 356(9225), 233-241. doi:10.1016/s0140-6736(00)02490-9 (https://www.sciencedirect.com/science/article/pii/S0140673600024909)
Greger, J. L. (2001). Selenium: Whats New? Nutrition Today, 36(2), 97-99. doi:10.1097/00017285-200103000-00016 (https://journals.lww.com/nutritiontodayonline/Abstract/2001/03000/Selenium__
What_s_New_.16.aspx)
N-Acetyl-L-Cysteine (NAC):
Mayer, M., & Noble, M. (1994). N-acetyl-L-cysteine is a pluripotent protector against cell death and enhancer of trophic factor-mediated cell survival in vitro. Proceedings of the National Academy of Sciences, 91(16), 7496-7500. doi:10.1073/pnas.91.16.7496 (http://www.pnas.org/content/91/16/7496.short)
Roederer, M., Staal, F. J., Raju, P. A., Ela, S. W., & Herzenberg, L. A. (1990). Cytokine-stimulated human immunodeficiency virus replication is inhibited by N-acetyl-L-cysteine. Proceedings of the National Academy of Sciences, 87(12), 4884-4888. doi:10.1073/pnas.87.12.4884 (http://www.pnas.org/content/87/12/4884.short)
Red Orange Extract:
Bonina, F. P., Puglia, C., Cimino, F., Trombetta, D., Tringali, G., Roccazzello, A. M., . . . Saija, A. (2005). Oxidative stress in handball players: Effect of supplementation with a red orange extract. Nutrition Research, 25(10), 917-924. doi:10.1016/j.nutres.2005.09.008 (https://www.sciencedirect.com/science/article/pii/S0271531705001806)
Bonina, F. P., Puglia, C., Frasca, G., Cimino, F., Trombetta, D., Tringali, G., . . . Saija, A. (2008). Protective effects of a standardised red orange extract on air pollution-induced oxidative damage in traffic police officers. Natural Product Research, 22(17), 1544-1551. doi:10.1080/14786410701740401 (https://www.tandfonline.com/doi/abs/10.1080/14786410701740401)
Puglia, C., Offerta, A., Saija, A., Trombetta, D., & Venera, C. (2014). Protective effect of red orange extract supplementation against UV-induced skin damages: Photoaging and solar lentigines. Journal of Cosmetic Dermatology, 13(2), 151-157. doi:10.1111/jocd.12083 (https://onlinelibrary.wiley.com/doi/full/10.1111/jocd.12083)