The Health Benefits of Brewer's Yeast

The potential benefits of Brewer's yeast include treating diabetes, irritable bowel syndrome (IBS), and respiratory ailments such as the common cold and the flu. It is also used in alternative medicine to prevent diarrhea and aid digestion.

Brewer's yeast is formed as a byproduct of beer-making. There is little research to back up the purported health claims about brewer's yeast and some possible side effects to be aware of.

Health Benefits

Brewer's yeast is the dried, deactivated (dead) cells of the fungus Saccharomyces cerevisiae. It is a rich source of B vitamins, protein, and minerals. One of those minerals—chromium—may help with controlling blood sugar. 

However, there is little research to back up the purported health benefits of taking brewer's yeast. Even so, alternative health experts claim the nutrients in it are beneficial.

Diarrhea

Researchers once thought brewer's yeast might treat diarrhea caused by the bacterium Clostridioides difficile (also known as C. diff).

However, more recent research has found that Saccharomyces boulardii, a different type of yeast that's also a probiotic, is effective against C. diff infection.

Irritable Bowel Syndrome

Brewer's yeast may help treat symptoms of irritable bowel syndrome (IBS). IBS is a digestive disorder that often causes abdominal pain, gas, diarrhea, and constipation.

According to a 2017 review of studies, people with IBS who took brewer's yeast were 51% more likely to have at least a 50% reduction in IBS symptoms compared to placebo.

It's important to note that this research review included only two trials and 579 participants in total. While promising, this research should be considered preliminary.

Upper Respiratory Tract Infections

Some people use brewer's yeast to treat the common cold, flu (influenza), and other upper respiratory tract infections. It isn't clear how brewer's yeast may fight these infections.

Some proponents claim it boosts the immune response in a way that helps your body "treat itself." Early, weak evidence suggests there may be something to this.

Some evidence also suggests that brewer’s yeast supplements may make upper respiratory tract infections less severe if you take it after you get sick.

Type 2 Diabetes

Brewer's yeast contains a form of chromium called glucose tolerance factor (GTC). GTC has been shown to improve the insulin response. Insulin is a hormone that helps convert sugar to energy.

GTC may help increase the activity of insulin in your blood. That might help treat insulin resistance, a condition that can lead to type 2 diabetes.

Early research on brewer's yeast for adults with type 2 diabetes is promising:

• A 2013 study reported a 9% drop in blood sugars.
• A 2015 study reported a small but positive effect on blood sugars.

Another 2013 study suggested brewer's yeast improved blood pressure (hypertension) in people with type 2 diabetes:

• Systolic pressure (upper number) dropped an average of 4.1 millimeters of mercury (mmHg).
• Diastolic pressure (lower number) fell 5.7 mmHg.

Safety

Brewer's yeast is generally considered safe for short-term use. However, it may cause side effects and negative drug interactions. It's also not safe for people with certain conditions.

Side Effects

Even "natural" treatments can cause side effects. In some people, brewer's yeast may cause:

• Headaches
• Stomach upset
• Gas
  

Contraindications (Who Shouldn't Take It)

Brewer's yeast isn't right for everyone. You may need to limit or avoid brewer's yeast if you have any of the following conditions:

• Yeast allergy
• Recurrent vaginal yeast infections
  
• Ulcerative colitis or Crohn's disease (animal research suggests it may worsen them.)
• Weakened immune systems for an organ transplant or advanced HIV (It may trigger a fungal infection.)

Pregnancy or Breastfeeding

Some animal studies have shown the strain of yeast in brewer's yeast may help increase milk production, but human studies haven't been done to confirm these findings.

Very little is known about the safety of brewer's yeast during pregnancy or breastfeeding. Ask your healthcare provider before using it.

Diabetes

Monitor your blood sugars carefully if you're on diabetes medications and start taking brewer's yeast. It may cause dangerously low blood sugar (hypoglycemia).

Drug Interactions

Brewer's yeast may interact with certain medications. Always let your healthcare provider and pharmacist know everything you're taking, including natural and nutritional treatments.

Check with your healthcare provider before combining brewer's yeast with any of the following medications.

Monoamine Oxidase Inhibitors (MAOIs)

MAOIs are often used to treat depression. They include:

• Marplan (isocarboxazid)
• Nardil (phenelzine)
• Emsam (selegiline)
• Parnate (tranylcypromine)

MAOIs work by keeping your body from breaking down tyramine (a substance in some foods). Brewer's yeast has large amounts of tyramine.

Taking brewers yeast with an MAOI could lead to a tyramine spike. That can cause a sudden rise in blood pressure known as a hypertensive crisis.

Demerol (Meperidine)

The narcotic Demerol (meperidine) is used to treat moderate to severe pain. It can also cause a hypertensive crisis when combined with brewer's yeast.

Antifungal Drugs

Brewer's yeast may interfere with antifungal drugs such as:

• Diflucan (fluconazole)
• Lamisil (terbinafine)
• Sporanox (itraconazole)

If you're taking brewer's yeast and have a fungal infection (including a yeast infection), be sure to let your healthcare provider and pharmacist know about the brewer's yeast (and anything else you're taking.) They can advise you as to the safest course of action.

Dosage and Preparation

No guidelines have been established for using brewer's yeast safely or effectively.

Brewer's yeast is available in tablet and powder forms. Tablets often come in doses of 250 to 1,000 milligrams. Brewer's yeast powder is usually mixed with water or other beverages. Most manufacturers recommend 1 to 2 tablespoons daily.

Brewer's yeast has a bitter flavor that some people don't like. It may help to mix it into a smoothie or juice.

What to Look For

You can find brewer's yeast online and at many health food stores.

Not all brewer's yeast products are the same. This is especially true of powdered brewer's yeast, which varies from brand to brand. Powders may be cheaper than tablets, but the nutrient content may be higher in the tablet. Check the label to be sure.

Try to choose 100% brewer's yeast without any fillers, additives, or sweeteners. Check to see if the packaging lists all the nutritional information, including the daily value (DV) of vitamins, minerals, protein, fiber, and fat. Many products don't.

Brewer's Yeast vs. Nutritional Yeast

Brewer's yeast is made from Saccharomyces cerevisiae. It is the byproduct of beer-making. The yeast cells are removed, pasteurized, and deactivated.

Nutritional yeast is also Saccharomyces cerevisiae but does not come from brewing. Rather, it is grown on corn, rice, or other types of grain.

Although they are almost the same thing, brewer's yeast has a bitter flavor, while nutritional yeast has a nutty, cheesy taste and a flakier texture.

Because of the more pleasant taste, vegetarians and vegans often use nutritional yeast in replacements for creamy or cheesy sauces or instead of parmesan cheese on pasta.

Beer Yeast and Baker's Yeast

Brewer's yeast is available in drugstores and health food stores. Beer yeast is usually only found in businesses that sell beer-brewing supplies.

Even so, beer yeast is often labeled as "brewing yeast." Unlike brewer's yeast, it is still active and can be bloomed (grown) to give beer its yeasty taste and fizzy carbonation.

The same applies to baker's yeast—sometimes it's used for brewer's yeast while others use it means active dry yeasts used to make bread rise.

Because the names can be confusing, store your brewer's yeast with your vitamins and medicine rather than in the pantry or spice cabinet. If you're not sure about a product's intended use, read the label or ask someone at the store.

Summary

Brewer's yeast is the deactivated form of the fungus Saccharomyces cerevisiae, which is different than the active form of yeast used in baking and beer making.

Some alternative medicine practitioners recommend taking brewer's yeast to help with IBS, diarrhea, colds, the flu, and diabetes. Little evidence supports the health benefits of brewer's yeast, and it may cause side effects and interact with certain medications.

Talk to your healthcare provider before taking brewer's yeast to be sure the possible benefits outweigh the risks.