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What to Know about Saccharomyces Boulardii: Benefits & Uses

Written by
March 15, 2019
Updated June 28, 2021

We often hear the phrase “go with your gut” when talking about abiding by one’s internal instinct. However, when it comes to your health, going with your actual gut is something you should do as well.

Having a healthy gut is not only important for optimal digestion and nutrient absorption, but there is also growing evidence that a balanced gut can support the body’s immune system too.

Enter your new best friend: Saccharomyces boulardii.

What to Know about Saccharomyces Boulardii: Benefits & Uses

What to Know about Saccharomyces Boulardii: Benefits & Uses

What Is Saccharomyces Boulardii?

While its name may be intimidating, don’t worry—Saccharomyces boulardii (pronounced “sack-car-oh-my-sees boo-lard-dee”) is not a new type of dinosaur. Rather, it’s a gut-friendly yeast that functions as a probiotic. Also known commercially as Florastor (as in gut flora), this yeast acts similarly to how the good bacteria in our body does; it neutralizes bad bacteria—pathogens that can wreak havoc in the gastrointestinal tract.

Probiotics in general are the friendly organisms, usually belonging to various bacterial strains,” says Shannon Ehrhardt, R.D., an EXOS Performance Dietician. “Saccharomyces Boulardii is a probiotic, but, unlike its bacterial counterparts, it’s actually a yeast. S. boulardii can be very beneficial for overall gut health, helping to maintain a healthy balance of good and bad microorganisms.”

Problems with the intestinal barrier can be linked to health issues within the GI tract. The digestive system is the first line of defense for the immune system, so having healthy gut flora helps keep harmful bacteria from getting into our bloodstream.

What Are The Benefits of Saccharomyces Boulardii?

Much like your best friend that hates your boyfriend but supports you anyway, S. boulardii can help you put up with a lot of shit. No, really, S. boulardii has been used for the last 30 years to support the gastrointestinal tract by helping protect the gastrointestinal barrier, which has the effect of making you more, er, regular.

For example, when taking antibiotics, digestive complications such as loose, watery stool can occur as the antibodies work to rid the body of bad bacteria. Unfortunately, this takes the good bacteria along with it. S. Boulardii has been shown to aid the body’s ability to control its normal eliminations.

Similarly, uncomfortable and irregular bowel complications can occur when traveling, especially to foreign countries. When consumption of strange or unusual foods or drinks that your body is not used to occurs during travel, S. boulardii administration has shown positive results.

S. boulardii supports the protection of the intestinal lining from harmful bacteria. It promotes a healthy immune system and the continued function of the gastrointestinal barrier, as well as aids digestive enzymes for nutrient absorption and digestion.

What Foods Have S. Boulardii?

What to Know about Saccharomyces Boulardii: Benefits & Uses

When initially discovered, S. boulardii was found to be in the fruits mangosteen and lychee. In 1920, French scientist Henry Boulard noticed that natives of IndoChina were using these plants by drinking the tea made from the fruit skins. He was later able to isolate S. boulardii (named for Boulard, if you hadn’t figured it out already) from these fruits, giving rise to its use in supplementation.

Outside of these foods, S. boulardii is hard to find in natural substances and is therefore most commonly consumed through over-the counter supplements (it’s included in Onnit’s Total GUT HEALTH™).

“With Total GUT HEALTH™, you not only have probiotics, but prebiotics as well, and betaine HCL—which promotes an optimal acidity level in the stomach,” says Ehrhardt. “It’s kind of a one-stop shop for everything your gut might need.”

It’s a good idea to actively include other probiotics in your diet alongside S. boulardii. You can get probiotic bacteria from kefir, sauerkraut, yogurt, miso, kombucha, and kimchi.

Can S. Boulardii cause bloating?

Some users have reported an increase of gas and bloating after taking S. boulardii. Otherwise, it is known to be safe for use in healthy individuals. Those with compromised immune systems should take caution and consult with a doctor before taking S. boulardii because, being a yeast, it comes from the fungus species and can lead to the presence of yeast in the blood.

How long does S. Boulardii take to work?

When taking S. Boulardii via capsule, the release of the yeast cells will occur within 30 minutes. The cells settle in the gut over about three days but will be absent from the system within roughly five days, according to the Denver Naturopathic Clinic. As S. boulardii is nonsystemic, it does not travel outside of the GI tract to the rest of the body.

For more about gut and digestive health, check out our articles “The Benefits of Digestive Enzymes”, “Gut Health – It All Starts with Gut Bacteria”, and “Gut Health, Probiotics, & The Effectiveness of the Mind”.

Sarah Smith is writer at Onnit. A former high school athlete, Sarah traded volleyballs for dumbbells while studying for her Bachelor's in Mass Communication. After graduation, she sought to navigate the increasing demands of adult life and a new marriage with her fitness goals. Because of that, she became certified in personal training from the National Academy of Sports Medicine to further her knowledge in health and wellness. She is passionate about writing and inspiring other women to live optimally, authentically, and relationally. When she's not writing or working out, Sarah can be found bingeing Star Wars for the millionth time (much to the annoyance of her husband) and drinking red wine. You can follow her ever-evolving wellness journey at @sarahtillersmith on Instagram.
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