According to the SK-II website , scientists spent years looking through yeast strains to isolate the Saccharomycopsis yeast strain that produces Pitera. Even today, we are constantly making new discoveries about its efficacy after 30 years. Sound too good to be true? As usual, I went onto PubMed to see what kind of scientific evidence there is for Pitera. After searching a variety of key words including Pitera, I finally found ONE study examining the effects of Saccharomycopsis Ferment Filtrate Pitera on reducing inflammation in mouse macrophage cells and on exerting protective effects on artificial human skin cells.