Probiotics are well-known for their ability to support digestive health, but not all probiotics operate in the same ways.

When it comes to resilience and targeted benefits for the gut, Saccharomyces boulardii—which just so happens to be a yeast, stands out from the crowd.

Unlike the majority of probiotics which are of bacterial origin, this clever probiotic yeast works in unique ways to help maintain balance, support gut barrier function, and defend against digestive disturbances. 

Let’s explore why this powerhouse probiotic is worth considering.

What is Saccharomyces Boulardii? 

Saccharomyces boulardii, also referred to as SB, is a beneficial, non-pathogenic yeast species first discovered in 1923 by a French microbiologist, Henri Boulard. He isolated it from lychee and mangosteen fruit peels while searching for natural remedies for diarrhoea. 

Unlike typical bacterial probiotics such as Lactobacillus and Bifidobacterium, Saccharomyces boulardii is a yeast which means it is naturally resistant to bacteria-killing antibiotics and stomach acid, allowing it to reach the intestines intact and provide its benefits. This makes it a particularly powerful option for supporting gut health during and after antibiotic use, as well as during bouts of digestive upset such as food poisoning and gastritis.

How Does Saccharomyces Boulardii Work? 

Saccharomyces boulardii supports digestive function in multiple ways:

1. Supports a Balanced Gut Microbiome – SB helps maintain microbial balance by competing with harmful bacteria and promoting a healthful environment for our beneficial flora.

2. Enhances Gut Barrier Function – SB strengthens the intestinal lining, helping to prevent toxins and pathogens from crossing into our bloodstream. It’s also seen as an effective rehabilitation tool for restoring microbial populations after surgery and antibiotic therapy.

3. Helps Combat Harmful Microorganisms – Studies suggest that SB can inhibit the growth of certain harmful bacteria, including Clostridium difficile, a nasty pathogen known to cause antibiotic-associated diarrhea and prolonged undesirable gut symptoms.

4. Modulates Immune Responses—SB interacts with the gut-associated immune system, supporting a balanced immune response and reducing inflammation. It also boosts secretory IgA, an important immune and inflammation-modulating immunoglobulin, contributing to immunity defences in the gut and throughout other areas of the body, such as the urogenital tract or respiratory tract.

5. Provides a Modulating Effect on Inflammation: SB has been shown to have a dual action on inflammation, by downregulating pro-inflammatory cytokines and upregulating anti-inflammatory cytokines, it can help to promote improvements to body-wide inflammation.

6. Improves Intestinal Brush Border Enzyme Activity: SB’s ability to enhance the gut environment also helps to improve brush border enzyme activity, which contributes to improving digestive capabilities and reducing food-related reactivity. 

Saccharomyces Boulardii vs. Other Probiotics 

Saccharomyces boulardii offers some unique advantages over traditional bacterial probiotics:

• Antibiotic-Resistant – Unlike many bacterial probiotics that are wiped out by antibiotics, SB can be taken alongside antibiotics to help protect gut health with no loss to its function.
  

• Heat & Acid Stable – As a yeast-based probiotic, it is naturally more resistant to stomach acid and temperature changes, making it a highly reliable probiotic choice.
  

• Rapid Action Against Digestive Disturbances – Clinical studies have shown SB can help reduce the duration and severity of episodes of diarrhoea, whether from travel-associated, antibiotics, or infection.

The Expanding Research on Saccharomyces Boulardii 

A growing body of research supports the wide-ranging benefits of Saccharomyces boulardii. Here are a few key findings:

• Antibiotic-Associated Diarrhoea (AAD): Multiple studies show that Saccharomyces boulardii can significantly reduce the risk of diarrhoea in individuals taking antibiotics, as well as help to maintain the gut environment so that good bacteria can continue to thrive.
  

• Irritable Bowel Syndrome (IBS) & Inflammatory Bowel Disease (IBD): Research suggests that this probiotic yeast can help reduce the unpleasant symptoms of IBS and IBD by modulating inflammation and improving gut barrier integrity. It can help sufferers by improving pain severity, flatulence, diarrhoea, stomach noise and burping.
  

• Traveller’s Diarrhoea: Clinical trials indicate that taking Saccharomyces boulardii before and during travel can help prevent digestive distress caused by unfamiliar or contaminated foods or water.
  

• Clostridium Difficile Infection: Studies show that Saccharomyces boulardii may help reduce the recurrence of C. difficile infections when used alongside standard treatments.
  

• Reduce Pathogenic Activity of Candida Albicans Infection: SB's multiple mechanisms of action on modulating immunity, inflammation, and antioxidant defences can help crowd out opportunistic candida infection and strengthen immune resistance.

Saccharomyces Boulardii and the Gut-Brain Connection 

The gut and brain are intricately linked, and research suggests that gut health plays a role in mental wellbeing. Saccharomyces boulardii supports a balanced gut microbiome, which in turn may positively influence mood, cognitive function, and stress resilience.

With its remarkable stability, unique mode of action, and well-documented benefits, Saccharomyces boulardii is an excellent probiotic choice for those looking to strengthen gut health, support immunity, and maintain overall digestive balance. Whether you are dealing with occasional digestive discomfort, taking antibiotics, or simply looking to optimise gut function, this powerful probiotic yeast is worth considering.

 

REFERENCES 

Pais P, et al. Saccharomyces boulardii: What Makes It Tick as Successful Probiotic? Journal of Fungi. 2020; 6(2):78. 

Jahn HU,et al. Immunological and trophical effects of Saccharomyces boulardii on the small intestine in healthy human volunteers. Digestion. 1996;57(2):95-104.

Buts JP, et al Effects of Saccharomyces boulardii on intestinal mucosa. Dig Dis Sci. 2006 Aug;51(8):1485-92. 

Kunyeit L, et al. Application of Probiotic Yeasts on Candida Species Associated Infection. J Fungi (Basel). 2020 Sep 25;6(4):189. 

Gu Y, et al. Saccharomyces boulardii, a yeast probiotic, inhibits gut motility through upregulating intestinal serotonin transporter and modulating gut microbiota. Pharmacological Research. 2022 July;181:106291.

McFarland LV. Systematic review and meta-analysis of Saccharomyces boulardii in adult patients. World J Gastroenterol. 2010 May 14;16(18):2202-22. 

Czerucka D, et al. Review article: yeast as probiotics -- Saccharomyces boulardii. Aliment Pharmacol Ther. 2007 Sep 15;26(6):767-78. 

Kelesidis T, et al. Efficacy and safety of the probiotic Saccharomyces boulardii for the prevention and therapy of gastrointestinal disorders. Ther Adv Gastroenterol. 2012 Jan;5(2):111-25.