Scientists have found that mixing fermented kefir with diverse prebiotic fibers produces stronger anti-inflammatory effects than taking omega-3 supplements or fiber alone. The combination, tested over six weeks in healthy adults, reduced a wider range of inflammatory markers in the blood than either approach by itself.
The study, led by researchers at the University of Nottingham, compared three popular dietary supplements: omega-3 fatty acids (500 mg daily), inulin fiber (20 grams daily), and a synbiotic blend of goat’s milk kefir plus 18 different prebiotic fibers. All three interventions lowered inflammation compared to controls who took nothing, but the synbiotic group showed the most dramatic changes.
Why the Combination Works Better
The synbiotic approach reduced seven different inflammatory proteins, including IL-6 and interferon-gamma, both linked to chronic disease risk. By contrast, omega-3 and fiber each lowered just one or two markers, primarily TNF-alpha. The effect sizes for the synbiotic group were notably larger: reductions in proteins like SIRT2 and 4EBP1 exceeded those seen with the other supplements by a substantial margin.
What makes the combination special? Kefir delivers live bacteria and yeasts from fermentation, including dozens of lactic acid bacteria strains. The prebiotic mix, containing fibers from sources like psyllium husk, maitake mushroom, quinoa, and chickpeas, feeds these microbes once they reach the gut. This creates a synergistic effect: the fiber nourishes the bacteria, which then produce metabolites like butyrate that calm inflammation throughout the body.
Butyrate levels rose significantly in the synbiotic group, and higher butyrate correlated with lower IL-6, a pro-inflammatory cytokine implicated in cardiovascular disease and metabolic disorders. This suggests the gut microbiome acts as a mediator, translating dietary components into systemic anti-inflammatory signals.
“Our study shows that while all three dietary approaches reduced inflammation, the synbiotic, combining fermented kefir with a diverse prebiotic fibre mix, had the most powerful and wide-ranging effects.”
The study enrolled 104 participants across three trials. The synbiotic trial included 40 people who consumed 170 ml of kefir plus 10 grams of the prebiotic blend daily, while others took omega-3 capsules, inulin fiber, or nothing. Blood samples were analyzed using Olink’s 96-protein inflammation panel, which captures a broad snapshot of immune activity.
Implications for Gut and Metabolic Health
Participants taking the synbiotic also saw reductions in total cholesterol, LDL, and non-HDL cholesterol, though these changes did not correlate directly with inflammatory protein shifts. The researchers note that the synbiotic group experienced drops in mucosal chemokines like CCL25 and CCL28, which are linked to gut lining inflammation and conditions like inflammatory bowel disease.
Dr. Amrita Vijay, who led the study, emphasized that the interaction between beneficial microbes and dietary fiber may be crucial for supporting immune balance. The findings align with earlier research showing that fermented foods produce more robust immune changes than isolated fiber supplements.
“This suggests that the interaction between beneficial microbes and dietary fibre may be key to supporting immune balance and metabolic health.”
The study has limitations. Sample sizes were modest, and the omega-3 and fiber groups were older on average than the synbiotic and control groups, which required statistical adjustments. The researchers did not analyze gut microbiome composition directly, though they plan to include metagenomic profiling in future work to clarify how synbiotics alter microbial communities and metabolic pathways.
Still, the results suggest that combining probiotics and prebiotics may offer a more effective, accessible dietary strategy for reducing inflammation than single supplements. The synbiotic used in the trial is commercially available, raising the possibility of translating these findings into practical recommendations, pending further testing in people with inflammatory conditions.
The next phase will involve trials in participants with specific health conditions to determine whether the synbiotic approach can deliver therapeutic benefits beyond what was observed in healthy volunteers.
Journal of Translational Medicine: 10.1186/s12967-025-07167-x
ScienceBlog.com has no paywalls, no sponsored content, and no agenda beyond getting the science right. Every story here is written to inform, not to impress an advertiser or push a point of view.
Good science journalism takes time — reading the papers, checking the claims, finding researchers who can put findings in context. We do that work because we think it matters.
If you find this site useful, consider supporting it with a donation. Even a few dollars a month helps keep the coverage independent and free for everyone.