Brewer’s yeast is a nutrient-rich food with many health benefits. This budding yeast is good for the gut and may boost both energy and immunity. However, it has some side effects and is not good for everyone. Read on to learn about the pros and cons of eating brewer’s yeast.
What Is Brewer’s Yeast?
Brewer’s yeast was originally produced as a by-product of beer brewing and has a bitter taste. Nowadays, it is dried and used as a nutritional supplement .
Specifically, it is made from Saccharomyces cerevisiae, a type of yeast that has been used in brewing and baking since ancient times .
S. cerevisiae has a wide arrange of purported beneficial health effects like lowering cholesterol, enhancing the immune system, and decreasing inflammation [3, 4].
“Brewer’s yeast” can refer to:
- The active form of S. cerevisiae that is used for brewing
- The leftover S. cerevisiae from the brewing process that is used as a supplement. This type has a strong bitter flavor
- S. cerevisiae that was grown on grain
Supplemental brewer’s yeast is typically grown on a medium of corn and other types of grain.
Brewer’s yeast is high in protein, B-vitamins, and chromium (some of the newer “debittered” forms don’t have chromium) .
However, the nutritional profile varies depending on the grain on which the yeast is grown, how it is processed, and whether it has been fortified with added nutrients .
In general, S.cerevisiae has:
- B Vitamins (B1, B2, B3, B6, Folate)
- Minerals (Potassium, Chromium, Zinc, Selenium, Lithium, Magnesium, Phosphorous, Copper)
- Prebiotics (Mannan-oligosaccharides (MOS), beta-glucans)
- Anti-inflammatories and immune stimulants (beta-glucans)
- Nicotinamide riboside
- Nucleotides: DNA and RNA
- Ergosterol  – these have pro and anti-estrogenic properties. It inhibits breast cancer.
Out of all these ingredients, the most interesting ones to many modern researchers are beta-glucans, nicotinamide riboside, and DNA and RNA nucleotides. Nucleotides in whole foods have recently been associated with increased energy and possibly even cognitive function [6, 7].
Is Brewer’s Yeast the Same as Nutritional Yeast?
Brewer’s yeast and nutritional yeast are close relatives, so it’s easy to confuse them. Nutritional yeast is also made from S. cerevisiae; the difference is in how the yeast is cultivated .
Their nutritional profile is also similar. Both are a rich source of B vitamins, which support the metabolism of carbohydrates, fats, and proteins. Unlike nutritional yeast, brewer’s yeast is also high in iron, selenium, zinc, and potassium. Brewer’s yeast is also a good source of protein, providing essential amino acids that the body doesn’t make by itself .
Although nutritional yeast is also a good source of protein and B-vitamins, it contains little to no chromium. It is usually fortified with vitamin B12 and folic acid (B9) .
And unlike brewer’s yeast, nutritional yeast has always been cultivated specifically for its nutrition. It’s grown on glucose medium, making it gluten-free; depending on the medium it’s grown on, brewer’s yeast may contain gluten .
Nutritional yeast is S. cerevisiae that is grown solely for supplemental use. It is usually fortified with vitamin B-12 and folic acid.
Benefits of Brewer’s Yeast
Supplemental brewer’s yeast has not been approved by the FDA for medical use. Supplements generally lack solid clinical research. Regulations set manufacturing standards for them but don’t guarantee that they’re safe or effective. Speak with your doctor before supplementing.
Insufficient Evidence For
The following purported benefits are only supported by limited, low-quality clinical studies. There is insufficient evidence to support the use of brewer’s yeast for any of the below-listed uses. Remember to speak with a doctor before taking brewer’s yeast as a supplement, and never use it in place of something your doctor recommends or prescribes.
1) Gut Health & Diarrhea
- cerevisiae is believed to promote gut health by:
- Clearing away bad bacteria while supporting good bacteria [8, 9, 10, 11, 12, 13]
- Preventing harmful bacteria and fungal toxins from sticking to the intestines [3, 14, 15, 16]
- Preserving gut barrier integrity [17, 18, 19]
- Decreasing inflammation 
- Fighting infections 
Many of these effects are mediated by the presence of prebiotics in S.cerevisiae (i.e. beta-glucans and mannan-oligosaccharides) as well as nucleotides [10, 3, 21].
Brewer’s yeast improved the outcome of C. difficile-associated diarrhea in humans, but the evidence is limited to a few individual cases .
However, brewer’s yeast lacks the probiotic effects, such as enhanced nutrient absorption and additional gut microbiome benefits. These are limited to supplements with live S. cerevisiae [23, 10, 24, 25, 26].
Saccharomyces boulardii is the only variant of yeast currently approved for probiotic use in humans because of its clinical effectiveness in treating diarrhea and other gut disorders. Talk to your doctor before using brewer’s yeast to manage diarrhea or any other gut condition [27, 28].
2) Type 2 Diabetes
Brewer’s yeast is naturally rich in glucose tolerance factor (GTF), a compound that contains a biologically-active form of chromium .
GTF decreased blood sugar, triglyceride, and LDL (“bad”) cholesterol levels and increased levels of HDL (“good”) cholesterol in rats and humans with type 2 diabetes .
It also prevented kidney and eye damage in diabetic animals .
Glucose tolerance factor achieves these effects by mimicking insulin. It can:
- activate proteins involved in insulin signaling pathways .
- enhance glucose transport .
- promote glycogen storage .
Glucose tolerance factor also enhanced the activity of insulin, helping it to bind to cells [31, 34].
Though some human studies have produced promising results, much more research is required to determine whether brewer’s yeast has a role in managing diabetes.
3) Energy and Mood
S.cerevisiae is a natural dietary source of nucleotides. Nucleotides enhanced endurance and post workout recovery in athletes, which may indicate a use for brewer’s yeast in reducing fatigue [35, 36].
Patients with chronic fatigue syndrome are often deficient in many nutrients, which can worsen symptoms. A nutritional supplement based on brewer’s yeast (Nagipol) improved cognitive function and mood in chronic fatigue syndrome patients. The authors suggested that brewer’s yeast may be a useful treatment for this poorly-understood disorder [37, 38].
Brewer’s yeast contains lithium, an element traditionally used to treat mood disorders. Naturally lithium-rich brewer’s yeast improved mood in former drug users .
However, this evidence is still considered insufficient to recommend brewer’s yeast for fatigue. Future studies will determine whether it is safe and effective for this purpose.
4) Healthy Skin
Cosmetic products containing S.cerevisiae extract improved skin moisture, brightness, and smoothness in volunteers .
These results could be explained by the abundant proteins, beta-glucans, vitamins and minerals in S.cerevisiae. These components are thought to have wound healing, hydrating, and antioxidant properties [41, 42, 40].
5) Healthy Weight
In a study of 54 obese men and women, yeast hydrolysate reduced body weight and stomach fat without any negative effects on lean body mass .
These results coincide with data from previous animal and human studies showing decreased body weight and body fat after yeast hydrolysate supplementation [44, 45].
Yeast hydrolysate is a nutritional supplement with processed and concentrated S. cerevisiae, and brewer’s yeast might not have the same effects on weight loss.
Yeast (from S.cerevisiae) reduces the hunger hormone ghrelin in mice, which may partly explain the loss in body weight [46, 45].
It also decreases fat production by reducing the activity of liver enzymes required for making fatty acids .
In addition, nicotinamide riboside (found in brewer’s yeast) increases enzymes involved in fat burning (sirtuins) and energy usage, thereby increasing weight loss .
The best way to lose weight is to eat a healthy diet and commit to an exercise plan. Brewer’s yeast may be a part of that healthy diet, but it’s important to talk to your doctor before using it, in order to avoid unexpected interactions or side effects.
6) Heart Disease
Dietary brewer’s yeast is under investigation for its potential against heart disease because it has improved cholesterol and blood pressure levels in animals and humans [48, 34, 49].
Brewer’s yeast contains many cholesterol-lowering vitamins and minerals:
- Beta-glucans 
- Niacin (which also increases HDL levels) 
- Nicotinamide riboside 
- Glucose tolerance factor 
Consuming brewer’s yeast daily lowered LDL cholesterol and triglyceride levels and increased HDL cholesterol in a small study of 55 type 2 diabetic patients with high blood cholesterol .
Aside from lowering cholesterol, brewer’s yeast may also reduce blood pressure. One study in 90 adults with type 2 diabetes found that brewer’s yeast significantly lowered blood pressure .
The high amounts of potassium, magnesium, and calcium in brewer’s yeast may explain this reduction in blood pressure. According to some studies, a greater intake of these minerals can reduce the risk of high blood pressure, heart disease, and stroke [34, 54].
Brewer’s yeast also contains proteins that help decrease blood pressure by decreasing the activity of the angiotensin-converting enzyme (ACE). Higher activity of this enzyme is linked to high blood pressure [55, 56, 57].
Brewer’s yeast has not been approved for the purpose of lowering cholesterol and should not be used in place of strategies and therapies recommended by your doctor.
7) Brain Health and Cognitive Function
Brewer’s yeast is a natural source of nicotinamide riboside, a form of vitamin B3 that is a precursor to nicotinamide adenine dinucleotide (NAD) .
Nicotinamide riboside safely raised levels of NAD in animals and humans .
Higher levels of NAD protect nerve cells and may prevent neurodegenerative disease [60, 61].
Increasing NAD levels with nicotinamide riboside restored cognitive function in a mouse model of Alzheimer’s disease .
In addition, nicotinamide riboside slowed nerve degeneration by stimulating NAD pathways, which may help preserve brain cells after injury .
More human studies will be required to determine what effect brewer’s yeast might consistently have on cognitive function and neural health.
8) Premenstrual Syndrome
Brewer’s yeast in combination with vitamins and minerals relieved premenstrual pain in 40 women with mild to moderate premenstrual syndrome .
Larger, more robust studies will be required to confirm this benefit.
Animal & Cell Research (Lacking Evidence)
No clinical evidence supports the use of brewer’s yeast for any of the conditions listed in this section. Below is a summary of the existing animal and cell-based research, which should guide further investigational efforts. However, the studies listed below should not be interpreted as supportive of any health benefit.
Beta-glucans (sugars found in the cell walls of yeast, bacteria, and fungi) can activate the immune system .
They enhance the function of the main immune system cells, including macrophages, neutrophils, and natural killer cells .
Beta-glucans bind to specific receptors on these cells, initiating a wide variety of beneficial immune responses (e.g., anti-inflammatory cytokine production) .
However, not all beta-glucans are equal. Beta-glucans derived from different sources have unique structures that result in different effects .
Cell research indicates that beta-glucans from yeast (i.e., beta-1–3-glucan) have the greatest capacity to activate the immune system .
Beta-glucans derived from S.cerevisiae have shown promising results including:
- Reduced incidence of bacterial, viral, and fungal infection in mice and humans [68, 69, 70, 71]
- Decreased allergy symptoms in mice and humans [72, 73, 74]
- Reduced occurrence of post-operative infection in animals and humans 
- Decreased inflammation and faster wound healing in animals and humans [76, 77]
- Reduced rate of cancer tumor size and growth in animals 
- Increased regeneration of white blood cells after radiation in mice 
- Decreased inflammation in mouse models of arthritis 
10) Hearing Loss
Nicotinamide riboside, a form of vitamin B3 found in brewer’s yeast, prevented noise-induced hearing loss in mice. It reduced nerve cell damage caused by noise exposure .
This effect has not yet been reproduced or even tested in humans.
S.cerevisiae is a rich dietary source of folate, a vitamin that helps prevent major birth defects [3, 82].
Oxidative stress is a major cause of high blood pressure in pregnancy that results in complications to the mother and fetus. S. cerevisiae reduced oxidative stress in maternal cord red blood cells, and the authors suggested that it may be useful in reducing oxidative damage to the fetus. However, this was a cell study, and their hypothesis has not been tested in living animals or humans [83, 84].
While the requirement for folate during pregnancy is well-established, the effect of brewer’s yeast on a pregnant woman or her unborn child is not certain. If you are pregnant, talk to your doctor about whether brewer’s yeast could be an appropriate addition to your diet.
Nicotinamide riboside (which is found in brewer’s yeast) extended the lifespan of yeast by increasing NAD synthesis and sirtuin activity .
It also promoted longevity in mice by improving mitochondrial function. Mitochondrial dysfunction is a key component in aging [86, 87].
These effects have not yet been tested in human studies. Much more research will be required to establish a link between brewer’s yeast and lifespan.
Side Effects & Precautions
This may not be a complete list of the potential side effects and interactions of brewer’s yeast. Talk to your doctor before supplementing to avoid unexpected adverse events.
- People allergic to candida, mold, or yeasts may react badly to brewer’s yeast [88, 89].
- Dietary intake of brewer’s yeast may increase the severity of Crohn’s disease and celiac disease in patients with antibodies to S.cerevisiae [90, 91, 92, 93].
- People who have kidney stones and gout should avoid brewer’s yeast (because of its high purine content) .
- Brewer’s yeast may worsen symptoms in people with eczema .
- Some brands of brewer’s yeast contain gluten and should be avoided in celiac disease patients .
Active yeasts used for fermentation (brewing and baking) have been observed to cause infections in people with candida or weakened immune system. On the other hand, supplemental brewer’s yeast contains killed S. cerevisiae with no potential to cause or worsen infections [1, 97, 98, 99].
Drug and Gene Interactions
Brewer’s yeast may interact with diabetes medications and lead to low blood sugar .
It has large amounts of tyramine, which can interact with monoamine oxidase inhibitors (MAOIs) and cause very high blood pressure .
People with MTHFR polymorphisms (MTHFR C677T and A1298C) have a reduced ability to process folic acid completely and thus should avoid brewer’s yeast fortified with synthetic folic acid [102, 103].
People with mutations in the Dectin-1, STAT1, STAT3, TLR4, and CARD9 genes may want to avoid brewer’s yeast because these variants are associated with impaired immunity and increased risk of fungal and yeast infections [104, 105, 106].
Genetic variants in the mannan-binding lectin (MBL) gene can lead to mannose-binding lectin deficiency, which is associated with higher anti-Saccharomyces cerevisiae antibody(ASCA) levels in Crohn’s disease patients [107, 108].
It’s important to talk to your doctor before adding brewer’s yeast to your diet or supplement regimen to avoid these or any other unexpected interactions.
How is Brewer’s Yeast Used
Brewer’s and nutritional yeasts are available in powder, liquid, or tablet form.
People who take brewer’s yeast as a supplement often take one to two tablespoons daily.
The powder form is usually mixed with water. You can also mix it into other beverages, such as juice, or add it to your smoothies. Have in mind that it’ll add a slightly bitter flavor to the drink. Some aren’t fans of the bitter aroma, but others enjoy it. It really comes down to experimenting with the flavors and finding the combination you like best.
Also, be sure to check the quality of the powder or tablets you’re buying. The powders are generally cheaper, but higher-quality supplements are less likely to contain additives or added sugars.
Buy Brewer’s Yeast
Brewer’s yeast is a nutrient-rich food with a variety of health benefits, including gut health support and preventing diarrhea.
This yeast is high in B vitamins, minerals, pre- and probiotics, and other healthful active compounds. Its characteristic bitter flavor can give your smoothies or juice a unique note. People who dislike bitter flavors may not like the taste of brewer’s yeast.
Note that some brewer’s yeast products contain gluten. If you’re sensitive to gluten, search for gluten-free brewer’s yeast, such as the type grown on beets.