Written by Chrystal Moulton, Science Writer. Results from subgroup analysis showed a significant decrease in CD25 expression on non-T cells and non-natural kill cells (P<0.05) following consumption of EpiCor®.

Gut health has long been an important topic in relation to overall health. Previous studies have demonstrated that disturbances in gut health can lead to significant chronic and cognitive disorders.^1-4 Probiotics in the form of fermentation products and capsules, as well as prebiotic products, have been marketed as remedies to support gut health.^5,6 However, postbiotic products, which comprise of components of inactive symbiotic microorganisms, have also been shown to exhibit beneficial changes in gut health.⁶ EpiCor® is formulated from a yeast (Saccharomyces cerevisiae) that has demonstrated clinical support for immune and gut health both in animal and human trials.^7-11 In the current study, researchers investigated the effects of a single dose of EpiCor® in human subjects on immune and inflammatory biomarkers.⁵

The study was designed as a randomized placebo-controlled crossover trial. Participants who were between 18-60 years of age with a BMI between 18-30 kg/m2 were recruited for the trial. All participants were required to conform to the requirements of the trial to be deemed eligible to participate and needed veins accessible for blood collection. The primary endpoints for this trial were:

1. Expression of CD25 and CD69 on cellular surface of natural killer cells
2. Changes in immune cell count

At the first visit, participants were required to consume the placebo or test product (based on their initial assignment) as a baseline, followed by a 1-week washout. Upon arrival, each participant completed a questionnaire to identify issues that may be affecting their health or overall stress levels. If answers to the questionnaire were satisfactory (no effect on health/stress detected), participants remained in the facility for baseline blood sample, followed by 3 additional samples collections after consumption of the placebo or test product at 1h, 2hrs, and 3hrs. After 1 week washout period, participants returned to the facility and the steps were repeated on the opposing protocol (either placebo or treatment) based on original assignment. The placebo product consisted of rice flour encapsulated in the same manner as EpiCor®, which was provided in a dark green veggie capsule at 500mg/capsule. Researchers used blood samples to evaluate 27 growth factors, cytokines, and chemokines, as well as immune cell count and their respective phenotypes that expressed CD25 and CD69 cell surface markers following consumption of either the test or placebo product.

A total of 30 eligible participants completed the study (males= 16, females=14). The average age of male participants was 31.1 ±11.2 years old, while female participants was 41.1 ±14.9years old. Mean BMI was 25.0 ±3.2 and 25.4 ±3.0 for female and male participants, respectively. Researchers observed a significant decrease in interferon-gamma and interleukin-1a one hour after consumption of EpiCor® compared to placebo (P<0.05). Two hours after consumption, researchers observed a significant decrease in interferon-gamma, interleukin-1a, interleukin-4, interleukin-7, and interleukin-8 (P<0.05). At hour 3, researchers observed a continued decrease in interleukin-1a and interleukin-8 (P<0.05). With regards to cell surface expression of CD25 and CD69 biomarker on immune cells, researchers observed non-significant changes specific only in non-T cell and non-natural killer cells. No changes were observed in other immune cell lines. During the trial, 3 participants were determined to represent a heterogenetic immunophenotype unlike the remaining 27 participants due to elevated CD25 expression (with no abnormalities). A subgroup analysis was conducted without data from those 3 participants. Results from subgroup analysis showed a significant decrease in CD25 expression on non-T cells and non-natural kill cells (P<0.05) following consumption of EpiCor®. No significant changes were observed for CD69 expression.

Overall, a single dose of EpiCor significantly reduced markers of inflammation like IL-1a, IL-4,7, and 8. Epicor® also demonstrated an immunomodulating trend affecting expression of CD25 on non-natural killer and non-T cells. Additional long-term studies will be needed to assess the anti-inflammatory and immunomodulating effects of EpiCor®.

Source: Jensen, Gitte S., David D. Cruickshank, Earvin AF Grinage, Dina Cruickshank, Krista Sanchez, Vicenta Garcia-Campayo, Neil D. Paton, and Justin B. Green. “A yeast-derived postbiotic fermentate rapidly modulates inflammatory cytokines and immune surveillance markers in healthy adults: a randomized double-blind placebo-controlled cross-over trial.” Frontiers in Nutrition 13 (2026): 1897550.

Click here to read the full text study.

Posted September 10, 2026.

Chrystal is a 2008 graduate of the University of Illinois at Chicago. She graduated with a bachelor’s in psychology with a focus on premedical studies and is a licensed project manager. She currently resides in Chicago.

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