The Health Benefits of Saccharomyces Boulardii

A Yeast That May Help With Diarrhea and More

Saccharomyces Boulardii capsules

Verywell / Anastasia Tretiak

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Saccharomyces boulardii is a type of yeast that comes from the skin of lychee and mangosteen fruits. It's long been used in certain systems of medicine and is now available in dietary supplement form.

Saccharomyces boulardii is thought to help treat a variety of gastrointestinal disorders that cause diarrhea. It's considered to be a probiotic, a type of beneficial bacteria that stimulates the immune system and protects digestive health.

This article discusses the health benefits of Saccharomyces boulardii and what researchers have found. It also covers the possible side effects, usual dosage recommendations, who should avoid it, and how to buy it.

Health Benefits

In alternative medicine, Saccharomyces boulardii is said to help with the following conditions:

  • Crohn's disease: a condition that causes inflammation in the gastrointestinal tract (digestive system)
  • Diarrhea: loose, watery, and frequent stools
  • Irritable bowel syndrome: an intestinal disorder that causes pain and changes in bowel habits
  • Ulcerative colitis: a condition that causes inflammation and ulcers in the colon and rectum

Some also use it for acne, canker sores, high cholesterol, urinary tract infections, and yeast infections.

Gastrointestinal Disorders

Saccharomyces boulardii may help treat or prevent certain gastrointestinal disorders according to a report from 2010.

For the report, investigators analyzed 27 clinical trials that used Saccharomyces boulardii for various diseases. They found significant evidence that Saccharomyces boulardii can help prevent traveler's diarrhea, which you can get from contaminated food or water. They also found it can prevent diarrhea associated with using antibiotics.

The report found that Saccharomyces boulardii shows promise in treating irritable bowel syndrome, acute adult diarrhea, and Crohn's disease. However, the authors note that more research is needed before Saccharomyces boulardii can be recommended for these conditions.

There's also some evidence that Saccharomyces boulardii may help treat ulcerative colitis, which causes inflammation and sores in the colon.

For instance, a 2003 study found that patients with ulcerative colitis may benefit from using Saccharomyces boulardii along with mesalazine. Mesalazine is an anti-inflammatory drug used to treat inflammatory bowel disease.

For the study, 25 patients with a mild to moderate flare-up of ulcerative colitis took Saccharomyces boulardii three times a day for four weeks. They did this along with their usual treatment of mesalazine. Of the 24 patients who completed the study, 17 went into remission by the study's end.

Saccharomyces boulardii may also help treat acute diarrhea in infants, according to a 2011 study.

The study involved 186 infants hospitalized within 72 hours after the sudden onset of diarrhea. Each of them received either Saccharomyces boulardii or a placebo (inactive substance) for five days.

Among the 176 infants who completed the study, those treated with Saccharomyces boulardii had a significantly shorter duration of diarrhea.


Research shows Saccharomyces boulardii may help prevent or treat some cases of diarrhea. There's some evidence it can improve conditions like ulcerative colitis, particularly when used along with conventional treatment. However, more research is needed before it's recommended as a treatment.

Possible Side Effects

Saccharomyces boulardii may cause certain side effects such as gas and bloating. In addition, there's some concern that using Saccharomyces boulardii may lead to fungemia, particularly for those with compromised immune systems. Fungemia is a condition marked by the presence of fungi in the blood.

Dosage and Preparation

There is not enough scientific data to provide a recommended dose of Saccharomyces boulardii. Various doses have been used when conducting scientific research.

For example, in a study investigating traveler's diarrhea, 250 to 1000 mg of Saccharomyces boulardii was used daily for one month. In a study to see the effects on diarrhea in people taking antibiotics, a dose of 250 to 500 mg of Saccharomyces boulardii was taken 2 to 4 times daily for up to two weeks.

In most cases, daily doses do not exceed 1000 mg daily.

The appropriate dose for you may depend on factors including your age, gender, and medical history. Speak to your healthcare provider to get personalized advice.

Warnings and Precautions

Like other supplements, there's still not enough research about the safety of using Saccharomyces boulardii.

Older adults, infants, those with a weakened immune system, and seriously ill patients should avoid using Saccharomyces boulardii or use only after consulting with a healthcare provider.

Saccharomyces boulardii hasn't been established as safe for pregnant women, nursing mothers, and children. Check with your doctor if you have a medical condition or are taking other medications.

Since Saccharomyces boulardii is a yeast, people with yeast allergies are advised to avoid using it.

Due to the limited research, it's too soon to recommend Saccharomyces boulardii as a treatment for any condition. Self-treating a condition and avoiding or delaying standard care may have serious consequences. If you're considering using it for any health purpose, make sure to consult your physician first.


Saccharomyces boulardii may not be safe for some people. This may include infants, older adults, those who are pregnant or breastfeeding, and those with weakened immune systems. Check with your doctor before taking it, especially if you have a current health condition.

How to Buy

Saccharomyces boulardii supplements are widely available for purchase online. They are also sold in many natural-food stores, drugstores, and stores specializing in dietary supplements.

Keep in mind that supplements haven't been tested for safety. Dietary supplements are largely unregulated. In some cases, the product may deliver doses that differ from the specified amount for each herb. In other cases, the product may be contaminated with other substances such as metals. 


Saccharomyces boulardii is a type of yeast that's available as a dietary supplement. In alternative medicine, it's used to help treat gastrointestinal conditions, including diarrhea.

Research shows it may help with certain digestive illnesses, including traveler's diarrhea. However, more research is needed before it can be recommended as a treatment, particularly for chronic conditions like Crohn's disease.

Saccharomyces boulardii may cause side effects like gas and bloating. Those with a weakened immune system may have an increased risk of fungemia, or fungi in the blood.

You should talk with your healthcare provider before taking it to make sure it's safe for you. Let them know about any other conditions and symptoms you have or medications you're taking.

6 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. U.S. National Library of Medicine, MedlinePlus. Saccharomyces boulardii.

  2. McFarland LV. Systematic review and meta-analysis of Saccharomyces boulardii in adult patients. World J Gastroenterol. 2010 May 14;16(18):2202-22. doi:10.3748/wjg.v16.i18.2202

  3. Guslandi M, Giollo P, Testoni PA. A pilot trial of Saccharomyces boulardii in ulcerative colitis. Eur J Gastroenterol Hepatol. 2003 Jun;15(6):697-8. doi:10.1097/00042737-200306000-00017

  4. Corrêa NB, Penna FJ, Lima FM, Nicoli JR, Filho LA. Treatment of acute diarrhea with Saccharomyces boulardii in infants. J Pediatr Gastroenterol Nutr. 2011 Nov;53(5):497-501. doi:10.1097/MPG.0b013e31822b7ab0

  5. Fadhel M, Patel S, Liu E, Levitt M, Asif A. Fungemia in a critically ill patient with acute cholangitis and long term probiotic use. Med Mycol Case Rep. 2019;23:23-25. doi:10.1016/j.mmcr.2018.11.003

  6. U.S. Department of Health and Human Services, National Center for Complementary and Integrative Health. Using dietary supplements wisely.

Additional Reading

By Cathy Wong
Cathy Wong is a nutritionist and wellness expert. Her work is regularly featured in media such as First For Women, Woman's World, and Natural Health.