Saccharomyces: A Common Yeast in the Gut Microbiome

Saccharomyces is a group of yeast species that can be members of a healthy gut microbiome [1]. It includes the species commonly found in Brewer's yeast, baker's yeast, and the popular sourdough starter. The most common species is Saccharomyces cerevisiae, which is used to make bread, wine, and beer. Extended exposure to S. cerevisiae can result in hypersensitivity [2]. This species has also been found in infections, particularly in those with weakened immune systems [3].

Some species can be more beneficial, though. The strain Saccharomyces boulardii can be found in certain probiotics and excels at protecting your gut from the undesired effects of antibiotics. To help your gut rebound, we recommend taking this strain during and after a course of antibiotics.

An emerging discovery with Saccharomyces (and its fellow fungi, Candida) is its link to a rare disorder called gut fermentation syndrome (GFS), or auto-brewery syndrome, where carbohydrates are metabolized to alcohol by fungi and/or bacteria in the digestive tract. GFS is a difficult-to-diagnose medical condition and may be associated with an increased risk of nonalcoholic fatty liver disease. Symptoms are similar to those of excessive alcoholic consumption and may include nausea, slurred speech and decreased social inhibition [4], [5].

We consider low or undetectable levels of Saccharomyces to be optimum. The best way to combat Saccharomyces is to encourage the growth of beneficial bacteria that will outcompete them for resources. (Adapted from Tiny Health)