Brewer’s YeastSupplement Forms/Alternate Names
Dried Yeast Fermentate; Faex; Faex Medicinalis; Levure De Biere; Medicinal Yeast;
Saccharomyces boulardiiPrincipal Proposed Uses
Protein Supplement; Treatment for Various Forms of
, including Traveler’s Diarrhea, Antibiotic-associated Diarrhea, and Acute Diarrhea
Other Proposed Uses
Cold and Flu (Prevention)
Irritable Bowel Syndrome
Brewer’s yeast, also known as
Saccharomyces cerevisiae, is commonly used in baking and the fermentation of beer; hence, the common name. Brewer’s yeast is rich in nutrients like
chromium, B vitamins, protein,
magnesium. It is the byproduct of beer brewing and can be grown on hops. Hops are the dried flowers that give beer its bitter taste. The yeast is separated from the beer after fermentation and processed. Aside from hops, the yeast can also be cultivated on other plants, like sugar beets.
Brewer’s yeast, along with its close cousin
Saccharomyces boulardii, is considered a probiotic. Probiotics are foods or dietary supplements that contain organisms, like bacteria or yeast, which provide health benefits for humans. Along with brewer’s yeast, another example of a probiotic is yogurt with live and active bacteria cultures.
Bacteria and yeasts naturally live in our bodies, mainly in the digestive tract. Probiotics contain “good” bacteria or yeasts that keep our digestive tract functioning properly, as well as keeping the population of harmful or “bad” organisms low.1
The probiotic activity of
S. boulardii in particular has been studied in the treatment of a number of conditions including:2, 3, 8
In addition to its probiotic benefits, Brewer’s yeast has been used as a protein supplement and is promoted as an energy and immunity enhancer.
This article covers both
Brewer’s yeast is usually sold in the form of a powder, flakes, liquid, or tablets. It can also be found as part of other food products, like fermented milks.7
For adults, brewer’s yeast can be taken at a dose of 1-2 tablespoons per day. The powder form can be added to food or mixed with water or juice.7
Probiotics, in general, should have several billion microorganisms per dose. This makes it more likely that the bacteria or yeasts will grow in the gut.3
A standard dose of
S. boulardii1 is 500 mg (milligrams) twice a day. This provides around 3 x 10 10-colony-forming units per gram. If taken to prevent antibiotic-associated diarrhea, for example, the yeast should be taken before and a few days after using antibiotics. The same is true for traveler’s diarrhea.1
The strongest evidence supporting the benefits of brewer’s yeast is for
diarrhea. Some studies have shown brewer’s yeast to be effective in preventing antibiotic-associated diarrhea, as well as relapsing colitis caused by the bacterium Clostridium difficile.
may fight this form of diarrhea by making enzymes
that counteract the effect of toxins produced by
C. difficile.2, 3
Since brewer’s yeast is a rich source of the mineral chromium, it has been studied for its ability to improve blood sugar control in patients with diabetes.6
There has also been interest in studying the effectiveness of brewer’s yeast for
lowering cholesterol, and
preventing colds and flu. However, it is still uncertain whether it is effective in these situations. 2, 4, 7
What Is the Scientific Evidence for Brewer’s Yeast?
Determining the effectiveness of brewer’s yeast, as well as other probiotics, is
hampered by the fact that many studies use combinations of differing bacterial and yeast
strains. This makes it difficult to know whether only one or all of the components are
needed for a beneficial effect. Nevertheless, a number of studies focusing only on
have shown beneficial effects.
Numerous studies have investigated the benefits of
S. boulardii5, 12, 13
in antibiotic-associated diarrhea and traveler's diarrhea in adults.
A mathematical analysis of ten randomized, controlled studies found
to be effective for the prevention of antibiotic-associated diarrhea.
In a controlled, double-blind study involving 3,000 Austrian tourists traveling
through hot climates, researchers found that
started five days
before departure and continued through the duration of travel significantly reduced the
incidence of traveler’s diarrhea compared to placebo. The effectiveness was dependent on
the dose given and its preparation.
A systematic review of studies focusing on the effectiveness of
difficile infection (the bacteria that causes antibiotic-associated diarrhea), found that the yeast may be effective in protecting against reoccurring infections, but not necessarily first-time infections.11
Other studies have also shown that
S. boulardii9, 10
may reduce the
duration of diarrhea in children.
Helicobacter pylori, a common bacterium present in the stomach and upper intestines of some people, is associated with an increased risk of peptic ulcers. Treatment for H. pylori
usually involves more than one antibiotic to suppress the
bacteria. While there is little evidence that
can help treat
H. pylori, it may effectively reduce the side effects associated with standard treatment for this condition.
One clinical trial, for example, compared two groups of children aged 3-18 years
infected with the
bacteria. One group
was given medicines to treat the infection plus
S. boulardii. The other group was given medicines plus a placebo. The group who took S. boulardii with their medicines had fewer side effects compared to the placebo group.14
Side effects included bloating, taste problems, and nausea.
Cold and Flu
A large, randomized trial found a positive effect for brewer’s yeast in preventing colds and seasonal influenza (flu). In the study, 116 adults who had received a flu shot were given either 500 mg of a brewer’s yeast product called EpiCor or placebo for 12 weeks. Researchers found that those who received Epicor had fewer colds and flu. And those on Epicor who did get a cold or flu were sick for a shorter length of time compared to participants taking placebo.4
Far more research is required before brewer’s
yeast can be routinely recommended for the prevention of colds and flu.
Brewer’s yeast, along with other probiotics, is generally considered safe. Some people may experience bloating or gas when taking probiotics.1
Those who should practice caution when using probiotics include people who are severely sick, have immune system issues, or those who have central venous catheters.3
People allergic to yeast or who are more likely to have yeast infections should not take
brewer’s yeast. Also, people with
diabetes should talk to their doctor before taking brewer’s yeast, since it can interact with their medicines and cause lower than expected blood sugar.7
Always talk to a doctor before taking any supplement or medicine.
Interactions You Should Know About
People taking any of the medicines listed below should exercise caution when taking brewer’s yeast:7
Antidepression MedicationsMonoamine Oxidase Inhibitors (MAOIs)
Brewer's yeast has a substance called tyramine in it. Tyramine can interact with
very high blood pressure
which can be dangerous (hypertensive crisis). This can
lead to a
Pain MedicationMeperidine (Demerol)
Taking brewer’s yeast while taking Demerol may cause hypertensive crisis.
References: [ + ]
Acidophilus and other probiotics. EBSCO Natural and Alternative
Treatments website. Available at:
http://www.ebscohost.com/thisTopic.php?marketID=15&topicID=114. Updated August 1, 2010. Accessed August 26, 2010.
Moyad MA. Brewer's/baker's yeast (
cerevisiae) and preventive medicine: part I.
Urol Nurs. 2007 Dec;27(6):560-561.
Jones K. Probiotics: preventing
J Spec Pediatr
Nurs. 2010 Apr;15(2):160-2.
Moyad MA, Robinson LE, Zawada ET Jr, et al.
Effects of a modified yeast supplement on cold/flu symptoms.
Urol Nurs. 2008 Feb;28(1):50-55.
McFarland LV. Systematic review and
in adult patients.
World J Gastroenterol. 2010 May 14;16(18):2202-2222.
Bahijiri SM, Mira
SA, Mufti AM, Ajabnoor MA. The effects of inorganic chromium and brewer's yeast
supplementation on glucose tolerance, serum lipids and drug dosage in individuals with
type 2 diabetes.
Saudi Med J. 2000 Sep;21(9):831-837.
Brewer’s yeast. University of Maryland
Medical Center website. Available at:
http://www.umm.edu/altmed/articles/brewers-yeast-000288.htm. Reviewed March 14, 2009. Accessed August 26, 2010.
Allen SJ, Okoko B, Martinez EG, Gregorio GV, Dans LF. Probiotics for treating
infectious diarrhoea. Cochrane Database of Systematic Reviews 2003, Issue 4. Art. No.:
CD003048. DOI: 10.1002/14651858.CD003048.pub2.
Szajewska H, Sko RKA A, Dylag M. Meta-analysis:
diarrhea in children.
Aliment Pharmacol Ther. 2007 Feb 1;25(3):257.
Makbule E, Dinleyici EC, Vandenplas Y. Clinical efficacy comparison of
and yogurt fluid in acute non-bloody diarrhea in children: a
randomized, controlled, open label study.
Am J Trop Med Hyg. 2010 Mar;82(3):488.
McFarland LV, Surawicz CM, Greenberg RN, et al. A
randomized placebo-controlled trial of
in combination with standard antibiotics for
JAMA. 1994 Jun 22-29;271(24):1913.
McFarland LV. Meta-analysis of probiotics
for the prevention of traveler's diarrhea.
Med Infect Dis. 2007 Mar;5(2):97-105.
Kollaritsch H, Holst H, Grobara P, Wiedermann G. Prevention of traveler's diarrhea with
Saccharomyces boulardii. Results of a placebo controlled double-blind study.
Fortschr Med. 1993 Mar 30;111(9):152-156.
Hurduc V, Plesca
D, Dragomir D, Sajin
M, Vandenplas Y. A randomized, open trial
evaluating the effect of
on the eradication rate of
infection in children.
Acta Paediatr. 2009 Jan;98(1):127-131.
Last reviewed December 2015 by EBSCO CAM Review Board
Last Updated: 12/15/2015
Back to Top