EpiCor (dried yeast fermentate)

Also called EpiCor, dried yeast fermentate, Saccharomyces cerevisiae fermentate, yeast postbiotic.

Best grade C across 5 graded outcomes Other Last checked Oct 21, 2026

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The short answer

From 10 sources

EpiCor is a dried baker's-yeast fermentate. In maker-funded trials, 500 mg a day for 12 weeks cut cold and flu-like symptoms in adults, eased hay-fever congestion, and lowered symptom severity in children, though not how often they got sick. A pilot trial found modest bloating and stool benefits. Nearly all studies were company-run.

Every graded outcome on this page

5 rows · line = participants

Grade CCold and flu symptoms in childrenColds and flun 256
Grade CCold and flu-like symptoms in vaccinated adultsColds and flun 116
Grade CCold and flu-like symptoms in unvaccinated adultsColds and flun 116
Grade CSeasonal hay-fever symptomsHay fevern 96
Grade CBloating and constipation symptomsDigestionn 80
2 more graded outcomes, in the evidence chapter

Key facts

What it is: A dried fermentate of Saccharomyces cerevisiae (EpiCor); a whole fermentation product, not a live probiotic^2,3
Top studied outcomes: Cold/flu-like symptoms in adults (C), hay-fever nasal congestion (C), cold/flu severity in children (C), bloating and stool form (C, subgroups)^2,3,4,5,6
Studied dose: 500 mg once a day in every trial, for 6 to 12 weeks^2,3,4,5,6
Null results: No effect on symptom severity in unvaccinated adults, and no change in how often children caught colds^3,6
Who paid: Trials were run or sponsored by the maker (Embria Health Sciences, later Cargill)^3,5,6,7
Safety data: Human trials lasted up to 12 weeks; lab tests found no genotoxicity or CYP1A2/CYP3A4 induction, and a 1-year rat study found no toxicity^4,6,9

What it is

EpiCor is a branded dried fermentate of baker's yeast (Saccharomyces cerevisiae), sold as a 500 mg immune supplement.

How it works

Proposed

In two small crossover studies in healthy adults (12 and 30 people), a single 500 mg dose shifted circulating immune-cell activation markers and lowered some cytokines (such as interferon-gamma and IL-8) within 1 to 3 hours compared with placebo. In a pilot trial it also changed gut bacteria. How these short-term changes relate to fewer symptoms has not been shown.^7,8,5

Forms

Form

The form on this page
Form	Elemental %	Absorption (human data)	GI tolerance	Studied for
Dried yeast fermentate (EpiCor)	Varies²Not applicable (a whole fermentation product, not a single compound)	No human absorption data. Single 500 mg doses changed blood immune markers within 1 to 3 hours in two small crossover studies.^7,8	Adverse events were similar to placebo in the hay-fever trial, the 2010 adult trial reported a better safety profile than placebo, and children tolerated it over 84 days.^3,4,6	Cold and flu-like symptoms, hay fever, gut comfort (500 mg/day)

What the human research says

Human trials only, one row per outcome. The form line shows what each trial actually tested. Grades follow our evidence-grading policy.

Trial map

5 graded outcomes, largest study first

5 graded outcomes: 2 improved, 3 mixed. The largest, a 2024 randomized trial of 256 people on cold and flu symptoms in children, found mixed results.

By sizeTable

1Cold and flu symptoms in children

Mixed · Grade C · RCT, 256 people, 2024

Children aged 4 to 12 attending school or daycare in Ontario, Canada, during the 2022-2023 flu season

Dose, result and source

Every graded outcome on this page, largest study first
Outcome	Found	People	Study	Who was studied
Cold and flu symptoms in children	Mixed	256	Grade C · RCT, 2024	Children aged 4 to 12 attending school or daycare in Ontario, Canada, during the 2022-2023 flu season
Cold and flu-like symptoms in unvaccinated adults	Mixed	116	Grade C · RCT, 2010	Adults with no recent seasonal influenza vaccination
Cold and flu-like symptoms in vaccinated adults	Improved	116	Grade C · RCT, 2008	Healthy adults recently vaccinated for seasonal influenza
Seasonal hay-fever symptoms	Improved	96	Grade C · RCT, 2009	Healthy adults with documented seasonal allergies and allergic rhinitis (US Midwest pollen season)
Bloating and constipation symptoms	Mixed	80	Grade C · Pilot RCT, 2017	Adults with gastrointestinal discomfort and reduced bowel movements (Belgium)

Every graded row

5 rows

Form tested

Showing 5 of 5 outcomes. Human trials only.

Grade CCold and flu symptoms in childrenColds and fluMilder colds, not fewerRCT
n 256 · 2024

Mixed Total symptom-severity scores, sore throat and muscle aches were lower with EpiCor during colds; placebo users were 1.73 times more likely to use cold/flu medicine. How often children had symptoms did not differ.

Design: RCT, n = 256, 2024
Population: Children aged 4 to 12 attending school or daycare in Ontario, Canada, during the 2022-2023 flu season
Form: EpiCor postbiotic (dried yeast fermentate)
Dose: 500 mg per day
Duration: 84 days
Source: Reference 6 · PubMed 38942887 (opens PubMed)

Grade CCold and flu-like symptoms in vaccinated adultsColds and fluFewer, shorter symptomsRCT
n 116 · 2008

Improved Participants taking EpiCor had significantly fewer cold/flu-like symptoms and a shorter duration of symptoms than those on placebo.

Design: RCT, n = 116, 2008
Population: Healthy adults recently vaccinated for seasonal influenza
Form: EpiCor dried yeast fermentate
Dose: 500 mg once daily
Duration: 12 weeks
Source: Reference 2 · PubMed 18335698 (opens PubMed)

Grade CCold and flu-like symptoms in unvaccinated adultsColds and fluLower incidence; no change in severityRCT
n 116 · 2010

Mixed Fewer people had cold/flu-like symptoms (incidence p = 0.01); the shorter duration was not significant (p = 0.10) and severity did not differ (p = 0.90).

Design: RCT, n = 116, 2010
Population: Adults with no recent seasonal influenza vaccination
Form: EpiCor dried yeast fermentate
Dose: 500 mg once daily
Duration: 12 weeks
Source: Reference 3 · PubMed 20180695 (opens PubMed)

Grade CSeasonal hay-fever symptomsHay feverLess nasal congestionRCT
n 96 · 2009

Improved During peak pollen weeks 1 to 6, nasal congestion (p = 0.04) and runny nose (p = 0.005) were less severe, with 12.5 fewer days of congestion; eye discharge did not improve significantly. Salivary IgA rose; adverse events were similar to placebo.

Design: RCT, n = 96, 2009
Population: Healthy adults with documented seasonal allergies and allergic rhinitis (US Midwest pollen season)
Form: EpiCor dried yeast fermentate
Dose: 500 mg once daily
Duration: 12 weeks
Source: Reference 4 · PubMed 19672568 (opens PubMed)

Grade CBloating and constipation symptomsDigestionSome symptoms better in subgroupsPilot RCT
n 80 · 2017

Mixed Bloating and fullness improved only in the moderate-symptom subgroup; stool consistency improved in the whole group at 2 weeks; the rise in stool frequency was not significant (p = 0.083).

Design: Pilot RCT, n = 80, 2017
Population: Adults with gastrointestinal discomfort and reduced bowel movements (Belgium)
Form: EpiCor dried yeast fermentate
Dose: 500 mg per day
Duration: 6 weeks
Source: Reference 5 · PubMed 28870194 (opens PubMed)

What the numbers add up to

Each point is worked out from the data and the sources numbered on this page, with the arithmetic shown under it. It adds no new data and is not medical advice.

Milder, not always fewer, colds

Results are mixed by outcome: one adult trial found fewer and shorter symptoms, a second found fewer colds but no change in severity, and the children's trial found milder colds but no fewer of them.^2,3,6

Evidence comes from the maker

The adult trials involved Embria Health Sciences employees and paid consultants, the gut trial was commissioned by Embria, and the 2024 and 2026 studies were co-written by Cargill staff. No independent replication was found.^3,5,6,7

Studied doses

Doses used in research, shown against the official limits. They describe the studies, not a recommendation for you.

Studied doses in research, not advice. These are amounts used in research, not personal advice. Your clinician or pharmacist can say what fits you.

Doses studied in human trials

Doses studied in human trials ranged from a single studied dose: 500 mg of EpiCor once a day, for 6 to 12 weeks in adults and for 84 days in children aged 4 to 12.^2,3,4,5,6

When trials measured an effect

2 outcomes

How long trials ran before effects were measured
Outcome	Measured at	Basis
Stool consistency	Week 2	6-week pilot in 80 adults: stool consistency improved in the whole group after 2 weeks; bloating eased at weeks 2 and 4 in the moderate-symptom subgroup⁵
Hay-fever nasal congestion	Weeks 1 to 6 (peak pollen)	12-week trial in 96 adults: nasal congestion and runny nose were less severe during the highest-pollen weeks 1 to 6⁴

Interactions and safety

Published interactions only: each row cites a source. No row means none was found in our sources, not that a combination is safe.

Interactions

0 agents

None found in our sources.

Check with what you take

Kept on this device only

Add what you take. We list every interaction our evidence profiles cite between EpiCor and your picks, and between your picks.

Add a supplement or medicine

Most cited:

Add a supplement or medicine you take to check it against EpiCor.

Starting from one medicine? The interaction checker rates how serious each pair is, on a curated list of 19 entries for 11 medicines. This cabinet has no severity rating: it lists every interaction row our supplement pages cite.

Who should be careful

2 groups

Pregnancy, breastfeeding and children: LactMed has no EpiCor entry. Its brewer's yeast entry (dead Saccharomyces cerevisiae cells, a different product) found no valid human studies on milk supply and mostly gastrointestinal side effects reported by nursing mothers. NCCIH notes that many supplements have not been tested in pregnant women, nursing mothers or children; one EpiCor trial enrolled children aged 4 to 12.^10,1,6
Medicines and surgery: NCCIH advises that supplements may interact with medications or pose risks before surgery, and to tell your health care providers about everything you use. In lab tests EpiCor did not induce the drug-metabolizing enzymes CYP1A2 or CYP3A4; no human drug-interaction study exists.^1,9

Safety

2 notes

Human safety data come from trials of 6 to 12 weeks.

Trial reports: Adverse events were similar to placebo in the hay-fever trial, the 2010 adult trial reported a better safety profile than placebo, and children aged 4 to 12 tolerated 500 mg a day for 84 days.^4,3,6
Lab and animal toxicology: No genotoxicity in bacterial or mouse lymphoma cell assays, no mitogenic effect on human lymphocytes, and no toxic signs or tissue damage in rats fed it for 14 days, 90 days or 1 year; the highest doses tested (1,500 mg/kg a day for 90 days, 800 mg/kg a day for 1 year) were the no-adverse-effect levels.⁹

How to read the label

What to check on the Supplement Facts panel.

How to read the label

1 checks

Look for 500 mg of EpiCor

Every trial used 500 mg of EpiCor a day. Combination products add other ingredients, such as vitamin D, that the trials did not test.^2,3,4,6

Have the bottle? Photograph its Supplement Facts panel and see each line, epicor (dried yeast fermentate) included, beside the doses and forms the trials used in Label X-Ray.

Where to buy EpiCor (dried yeast fermentate)

Products from brands we partner with that contain EpiCor (dried yeast fermentate). Check the amount per serving against the doses studied above, and the label for other ingredients.

EpiCor (dried yeast fermentate) products from partner brands

1 product Paid links · we earn a commission

HerbsProSource Naturals Epicor with Vitamin D-3, 500 mg, 60 capsules
1 capsule: EpiCor dried yeast fermentate 500 mg plus vitamin D3 2,000 IU (the trials used EpiCor without vitamin D)
$26.59one-timeChecked Oct 15, 2026
Shop at HerbsPro (paid link, opens in new tab)

Frequently asked questions

Short answers to common questions; the numbers link to the sources below.

Common questions

6 answers

Is EpiCor a probiotic?

No. EpiCor is a dried fermentate of baker's yeast (Saccharomyces cerevisiae): the yeast is fermented and dried into a powder, so it does not contain live organisms the way a probiotic does. The 2024 children's trial calls it a postbiotic.^2,3,6

Does EpiCor mean fewer colds or milder ones?

Two 12-week adult trials of 116 people each found fewer cold/flu-like symptoms with 500 mg a day; one also found shorter symptoms, the other no change in severity. A children's trial found milder but not fewer colds.^2,3,6

Can children take EpiCor?

A trial gave 500 mg a day to 256 children aged 4 to 12 for 84 days and found it well tolerated. NCCIH notes that many supplements have not been tested in children, so ask a pediatrician.^6,1

Is the research independent?

No. The trials were run, commissioned or co-written by the maker, Embria Health Sciences, and later Cargill.^3,5,6

What are the side effects of EpiCor?

Trials reported few problems: adverse events were similar to placebo in the hay-fever trial, the 2010 adult trial reported a better safety profile than placebo, and children tolerated 500 mg a day for 84 days. Lab and rat studies found no genotoxicity or organ damage.^4,3,6,9

Is EpiCor safe to take long term?

Human trials lasted at most 12 weeks, so longer use is unstudied in people. Rats fed it for 1 year showed no toxic signs or tissue damage at up to 800 mg/kg a day.^2,3,9

Sources

10 sources: trial abstracts, NIH fact sheets and reference databases. Numbers in the text link here.

Sources cited on this page

10 sources

1Using Dietary Supplements WiselyFact sheet National Center for Complementary and Integrative Health (NCCIH), 2019 · nccih.nih.gov
2Effects of a modified yeast supplement on cold/flu symptoms.RCT Urol Nurs, 2008 · PMID 18335698
3Immunogenic yeast-based fermentate for cold/flu-like symptoms in nonvaccinated individuals.RCT J Altern Complement Med, 2010 · PMID 20180695
4Immunogenic yeast-based fermentation product reduces allergic rhinitis-induced nasal congestion: a randomized, double-blind, placebo-controlled trial.RCT Adv Ther, 2009 · PMID 19672568
5A yeast fermentate improves gastrointestinal discomfort and constipation by modulation of the gut microbiome: results from a randomized double-blind placebo-controlled pilot trial.Pilot RCT BMC Complement Altern Med, 2017 · PMID 28870194
6Efficacy of a yeast postbiotic on cold/flu symptoms in healthy children: A randomized-controlled trial.RCT Pediatr Res, 2024 · PMID 38942887
7A yeast-derived postbiotic fermentate rapidly modulates inflammatory cytokines and immune surveillance markers in healthy adults: a randomized double-blind placebo-controlled cross-over trial.Crossover RCT Front Nutr, 2026 · PMID 42625679
8Antioxidant bioavailability and rapid immune-modulating effects after consumption of a single acute dose of a high-metabolite yeast immunogen: results of a placebo-controlled double-blinded crossover pilot study.Crossover RCT J Med Food, 2011 · PMID 21501093
9Safety evaluation of a proprietary food-grade, dried fermentate preparation of Saccharomyces cerevisiae.Animal study Int J Toxicol, 2012 · PMID 22222580
10Brewer’s YeastDatabase LactMed (NCBI Bookshelf), 2026 · ncbi.nlm.nih.gov

What changed

Every dated change to this page: what changed, who made it and why.

Change log

2 entries

Dated changes to this page
Date	Change	Who and why
Oct 21, 2026key facts, who should avoid, safety, time to effect, FAQ, questions, related	Added the 2012 EpiCor safety evaluation (no genotoxicity, no CYP1A2 or CYP3A4 induction in lab tests, no toxicity in rats for up to 1 year) as a safety section and medicines note; a breastfeeding note citing LactMed's brewer's yeast entry (LactMed has no EpiCor entry); time-to-effect rows from the gut pilot (week 2) and hay-fever trial (weeks 1 to 6). Replaced FAQ items that repeated the page's own questions (what it is, hay fever) with probiotic status, side effects and long-term safety; added page questions and goal-hub links. Interactions: no human interaction study, LiverTox or LactMed entry for EpiCor exists, so the list stays empty. PubMed searched through October 2026 for newer EpiCor or yeast-postbiotic human trials: none beyond the 2024 children's trial and the 2026 crossover already cited.	Writer: Kymata Health EditorialTrigger: A–Z audit against docs/supplements/AUDIT-STANDARD.md
Oct 15, 2026all	Initial editorial evidence review. Every PMID checked against NCBI E-utilities esummary (title, year, journal; none retracted) and each cited abstract read; every number in the evidence rows comes from the abstracts. Funding and conflicts disclosed per study from the abstract statements: Embria Health Sciences employees and consultants (2010 trial), Embria-commissioned gut pilot (2017), Cargill co-authors (2024 children's trial and 2026 crossover). The 2008 and 2009 abstracts name no funder, so we note the same team's Embria ties instead. Safety rows use NCCIH's general supplement guidance only; no EpiCor-specific page exists on our approved safety sources (ODS, NCCIH, LactMed, LiverTox, Health Canada, EMA). Where to buy: Source Naturals Epicor with Vitamin D-3 (label checked 2026-10-15).	Writer: Kymata Health EditorialTrigger: new page

Supplement & Nutrient Encyclopedia. Educational information only; it is not medical advice and does not replace a clinician. Dietary supplements are not intended to diagnose, treat, cure or prevent any disease. Statements about supplements have not been evaluated by the FDA.