Yeasts as probiotics Since very early times, around 1550 BCE, humans have been using yeasts in various fermentation processes. Today yeasts have become an important part of many commercially important sectors, including foods, beverages, pharmaceuticals,industrial enzymes and others. Yeast especially, Saccharomyces cerevisiae boulardii has aQPS (Qualified Presumption of Safety)status according to EFSA (The European Food Safety Authority) and is widely used as a probiotic throughout the world due to its established health benefits. It is the only yeast commercialized for human use