A single dose of EpiCor postbiotic was associated with measurable changes in immune-related biomarkers within hours of consumption, according to a new human clinical study published in Frontiers in Nutrition.
The randomised, double-blind, placebo-controlled crossover trial involved 30 healthy adults who were aged 18-60.
Participants consumed either a 500 mg dose of EpiCor, a yeast-derived Saccharomyces cerevisiae fermentate, or a rice-flour placebo at separate clinic visits, with a one-week washout period between visits.
Blood samples were collected at baseline and one, two and three hours after consumption.
Researchers assessed circulating immune cell subsets and activation markers, alongside a panel of 27 cytokines, chemokines and growth factors.
The research was conducted at NIS Labs and funded by Cargill, the manufacturer of EpiCor.
Rapid immune response
Compared with placebo, EpiCor consumption was associated with significant changes in several immune-related biomarkers during the three-hour observation period.
At one hour, IFN-γ and IL-1ra levels were significantly lower after EpiCor consumption.
At two hours, significant reductions were observed for interleukins IL-4, IL-7 and IL-8.
IL-1β, IL-5 and TNF-α also showed downward trends.
The researchers did emphasise that the findings did not indicate broad suppression of immune activity. Instead, the changes were concentrated among specific inflammatory pathways and were accompanied by alterations in the distribution of CD25-positive immune cell subsets.
Changes in circulating immune cells did not reach statistical significance across all measures.
However, the researchers observed changes in the proportion of CD25-positive natural killer T cells and other immune cell populations, which they interpreted as consistent with altered immune cell trafficking.
The study therefore provides mechanistic insight into EpiCor's potential early biological effects, rather than demonstrating a new clinical immune-health outcome.
Postbiotic mechanism remains under investigation
The authors proposed that the rapid response could involve signalling between the gut and immune system, potentially including neuroimmune pathways and vagal signalling.
However, they stressed that the trial was not designed to directly test these mechanisms, meaning the proposed gut-vagus pathway remains a hypothesis.
The researchers did also note several limitations with the study, including the small sample size, the restriction to healthy adults and the short three-hour follow-up.
The study also only measured circulating biomarkers rather than clinical endpoints or direct measures of gut function.
This is particularly relevant as the postbiotic category continues to develop, with suppliers and manufacturers increasingly looking to substantiate health-positioning with robust human evidence.
As consumers become more discerning about claims made by supplements and functional nutrition products, science-backed ingredients with clinical and mechanistic data can help brands differentiate products and build credibility.
The authors concluded that the findings support further investigation of EpiCor as an acute nutritional modulator of immune signalling, while suggesting that these early responses could contribute to mechanisms underlying previously reported longer-term effects.
