Saccharomyces boulardii

Health Tips / Saccharomyces boulardii

What Is It?

Saccharomyces boulardii (SB) is a yeast that promotes gastrointestinal health. This microorganism, which is sold as a supplement, is a “probiotic.” Probiotics help maintain a normal balance of beneficial bacteria in the intestinal tract. Well-known probiotics include the lactobacilli and bifidobacteria found in yogurt.

SB is widely used in Europe for preventing and treating diarrhea associated with antibiotics, travel, and the inflammatory bowel condition Crohn’s disease. SB may be useful for people with Candida overgrowth syndrome as well. Also a yeast, Candida is just one of the many microorganisms that live in the gastrointestinal tract. However, an excessive amount of this particular resident can produce powerful toxins that are absorbed into the bloodstream. Bloating, gas, diarrhea, fatigue, headache, depression, and recurrent yeast infections are some of the many symptoms of Candida overgrowth.

Although it is not known exactly how SB works, three theories prevail. One is that it interferes with the binding of infectious agents to cells in the gut. Another is that it increases the amount of immune proteins that fight intestinal invaders. Finally, it is possible that SB simply beats Candida and other unwanted organisms when competing for space in gut.

General Interaction

Certain antifungal medications may, in addition to fighting the offending fungus, eliminate SB as well. Be sure to tell your doctor about all the pills that you are taking, including this dietary supplement.

Alcohol can inactivate SB, so stick to nonalcoholic beverages while taking this supplement.


Few adverse reactions are associated with SB. People who are allergic to yeast should certainly avoid it, or itching and facial swelling could result.