Kefiran

PrebioticBest with a meal

What is it

Kefiran is an exopolysaccharide produced by Lactobacillus kefiranofaciens and related microorganisms in kefir grains. It is a soluble fiber-like polysaccharide composed of glucose and galactose units.

Evidence for 1 use

AI-assisted evidence assessment — talk to your doctor before relying on any single supplement.

Gut microbiota modulation

Mixed Evidence

Preclinical data suggests prebiotic and microbiota-modulating effects. Human evidence for isolated kefiran is sparse.

How it works

As a non-digestible polysaccharide, kefiran reaches the colon largely intact, where it can be fermented by resident microbiota into short-chain fatty acids. Animal and in vitro studies have reported antimicrobial, immunomodulatory, anti-inflammatory, and modest blood pressure-lowering activity. Direct human clinical evidence for isolated kefiran is limited. Most kefir clinical research evaluates the whole fermented product (which contains bacteria, yeasts, peptides, and kefiran) rather than the polysaccharide alone.

Dosage

There is no established evidence-based dose for isolated kefiran. Whole kefir intake in studies is typically 200–500 mL/day. DSLD label data is limited.

When and how to take it

When consumed as kefir, no specific timing needed. Take with meals.

1 commercial form

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Kefir-derived polysaccharide

Practical source is consumption of kefir.

Non-digestible; fermented in colon.

Safety

Considered safe at amounts consumed in fermented dairy products. Isolated polysaccharide supplementation has not been extensively studied for high-dose safety.

Who should be cautious

Generally well tolerated. People with dairy allergy or severe lactose intolerance should consider source.

Interactions

No clinically established interactions.

Food sources

Kefir (fermented milk)

Amount
Variable per cup
%DV
—

Frequently asked questions

Is kefiran a probiotic?⌄

No. Kefiran is a polysaccharide produced by kefir microbes; it is a prebiotic substrate, not a probiotic itself.

References

Kefiran on Wikidata — Wikidata link

Kefiran (PubChem CID 90908346) — PubChem link

Kefiran on NIH DSLD (US supplement label database) — NIH Dietary Supplement Label Database link

Research on Kefiran (PubMed search) — PubMed link

Track Kefiran with Pilora

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Evidence-based·How we grade evidence

Disclaimer: These statements have not been evaluated by the FDA. This page is educational, not a substitute for personalized medical advice. Evidence grades are AI-assisted assessments — talk to your doctor before starting any new supplement, especially if you’re pregnant, breastfeeding, on medications, or managing a chronic condition.