“Saccharomyces cerevisiae?”Here!baker's/brewer's yeast
Hasn’t appeared in a scanned product yet.
As a supplement
Talk to your doctor or pharmacist.
Roll Call does not check drug interactions or assess personal safety.
A species of yeast used widely in baking, brewing, and as a source of nutrients or live cultures in some supplements. It is a different species from the more studied probiotic strain Saccharomyces boulardii.
Why it’s used
Taken by some as a source of B vitamins, protein, or as a general probiotic, though claims vary by product.
What the evidence says
There is no NIH Office of Dietary Supplements fact sheet specific to this species, and clinical research on plain Saccharomyces cerevisiae (as distinct from S. boulardii) for digestive or immune effects is limited and inconsistent.
Where we looked
There was no paper to cite here, so this is the search instead — run it yourself and see what we saw.
- PubMed: 12860 records · searched September 2026
"Saccharomyces cerevisiae"[Title/Abstract] AND (review[pt] OR "safety assessment"[Title/Abstract] OR "risk assessment"[Title/Abstract] OR toxicology[Title/Abstract] OR toxicity[Title/Abstract] OR characterization[Title/Abstract] OR characterisation[Title/Abstract]) - PubMed: 35 records · searched September 2026
"Saccharomyces cerevisiae"[Title/Abstract] AND ("dietary supplements"[MeSH] OR supplementation[Title/Abstract] OR supplement[Title/Abstract] OR supplements[Title/Abstract] OR "oral administration"[Title/Abstract]) AND (randomized controlled trial[pt] OR clinical trial[pt] OR meta-analysis[pt] OR systematic review[pt]) AND humans[MeSH] - PubMed: 81483 records · searched September 2026
"Saccharomyces cerevisiae"[Title/Abstract]
This says what this database holds under these terms. It is not a finding that no research exists.
Context
Much of the probiotic literature that gets attributed loosely to "yeast" supplements actually concerns the distinct strain S. boulardii, which complicates comparison.
Rumors
Brewer's yeast supplements cause gas, bloating and headaches.
Does not support — suggestivehealth and safety evidence
Studied in: breastfeeding women using brewer's yeast as a galactagogue.
Measured as an outcome.
- Use and experiences of galactagogues while breastfeeding among Australian women (Peer-reviewed) · Funded by Australian Government Research Training Program Scholarship; NHMRC; The Hospital Research Foundation; Robinson Research Institute (government) · No conflicts declared
- Brewer’s Yeast - Drugs and Lactation Database (LactMed®) - NCBI Bookshelf (Regulatory) · Funding not checked
Who’s saying this
- Healthline — a publisher: health information publisher; part of RVO Health, backed by Red Ventures and UnitedHealth Group's Optum
How we know who this is
- “Healthline is a digital publisher and does not offer personal health or medical advice.” (their page)
- “Healthline is part of RVO Health, a company backed by Red Ventures and UnitedHealth Group’s Optum.” (their page)
Taking brewer's yeast promotes Candida yeast infections.
Does not support — suggestivehealth and safety evidence
Studied in: immunosuppressed mice with oropharyngeal/vaginal candidiasis.
Measured as an outcome.
- Saccharomyces cerevisiae CNCM I-3856 as a New Therapeutic Agent Against Oropharyngeal Candidiasis (Peer-reviewed) · Funding not checked
Who’s saying this
- The Health Board — a publisher: health information site funded by ads and affiliate commissions
How we know who this is
- “The Health Board provides evidence-based knowledge to live your healthiest, happiest life.” (their page)
- “We sustain our operations through affiliate commissions and advertising.” (their page)
Brewer's yeast lowers blood sugar and helps control type 2 diabetes.
Supports — suggestivehealth and safety evidence
Studied in: adults aged 35-55 with type 2 diabetes mellitus.
Measured as a biomarker.
- Brewer's Yeast Improves Glycemic Indices in Type 2 Diabetes Mellitus (Peer-reviewed) · Funded by Research Undersecretary of Tehran University of Medical Sciences
Who’s saying this
- Healthline — a publisher: health information publisher; part of RVO Health, backed by Red Ventures and UnitedHealth Group's Optum
How we know who this is
- “Healthline is a digital publisher and does not offer personal health or medical advice.” (their page)
- “Healthline is part of RVO Health, a company backed by Red Ventures and UnitedHealth Group’s Optum.” (their page)
Brewer's yeast increases breast milk supply.
Does not support — establishedhealth and safety evidence
Studied in: mothers of preterm infants in NICU.
Measured as an outcome.
- Brewer’s Yeast - Drugs and Lactation Database (LactMed®) - NCBI Bookshelf (Regulatory) · Funding not checked
- Use and experiences of galactagogues while breastfeeding among Australian women (Peer-reviewed) · Funded by Australian Government Research Training Program Scholarship; NHMRC; The Hospital Research Foundation; Robinson Research Institute (government) · No conflicts declared
Who’s saying this
- milky-mama.com — we haven’t checked who runs this site yet
Feeding brewer's yeast to dogs repels fleas and ticks.
Does not support — suggestivehealth and safety evidence
Studied in: dogs.
Measured as an outcome.
- Failure of brewer's yeast as a repellent to fleas on dogs (Peer-reviewed) · Funding not checked
Who’s saying this
- Only Natural Pet — a retailer: sells natural pet products from 200+ brands, including its own line
How we know who this is
- “Only Natural Pet was founded in Boulder, Colorado in 2002.” (their page)
- “At Only Natural Pet, every product we carry is vetted to meet our high standards for health, safety and sustainability.” (their page)