Weissella cibaria JW15,
does it really help with Enhanced immune function and defense against infection?
research showsIn a double-blind RCT of 100 participants, JW15 at 1×10^10 CFU/day for eight weeks increased NK-cell activity, while IFN-γ and IgG1 did not change significantly. The study did not test whether colds or infections were reduced, and evidence from one strain, one trial, and immune surrogate markers supports C.
ads claimImmune enhancement, viral defense, and cold prevention are distinct claims. The trial directly supports only NK-cell activity under specified assay conditions.
Useful facts when choosing a product
- Original recognition 2022-20 coexists with duplicate recognition 2022-35 for the same ingredient.
- The daily intake is JW15 1×10^10 CFU; strain identity and guaranteed viable count matter.
- People with illness or immune vulnerability need professional advice.
Chamgap Semantic Classification Code
Candidate index · review held
UNK.weissella-cibaria-jw15.UNK.immune-function-and-defense-against-infection.improve.placeboUnknown > Weissella cibaria JW15 > Unknown > immune function and defense against infection > Improvement claim > Placebo
An automated migration candidate, not an issued permanent code; exact claim scope remains under review. This machine-generated migration candidate helps retrieval but is not a permanent assignment. The original verdict ID and URL remain authoritative.
What the research actually shows
Lee 2018 randomized 100 nondiabetic adults to JW15 at 1×10^10 CFU/day or placebo for eight weeks and analyzed 82. NK-cell activity increased, but IFN-gamma and IgG1 did not change significantly, and infection incidence was not measured. Funding came from a Rural Development Administration program. The same ingredient has both the original recognition number 2022-20 for the National Institute of Agricultural Sciences and duplicate recognition number 2022-35 for Huons Foodience.
Why this is classified as C (47)
A strain-specific 100-participant RCT exists, but evidence is one trial using NK-cell surrogate markers without clinical infection outcomes, supporting C with 47 points.
Counterpoint. A positive human signal remains for the immune-marker subclaim, but it does not extend to defense against infection.
Rejudgment record. Reassessment (cross-check reflected) — A publicly funded RCT analyzed 82 of 100 participants; only the NK-cell surrogate was positive, IFN-gamma and IgG1 were null, and infection incidence was not measured
Sub-claim grades by effect
This ingredient is marketed for several effects. A single overall grade blends strong and weak claims together, so each effect is graded separately here. The overall grade reflects the strongest disconfirming or core claim.
| Effect (sub-claim) | Grade | Basis |
|---|---|---|
| Improvement of immune markers (NK cells) | C | Surrogate marker only |
| Protection against actual infections | ? | Infection incidence was not measured |
Cross-check — AI research and Codex final gate
Evidence Table
| Study | Design | Sample | Funding | Endpoint | Result | Weight |
|---|---|---|---|---|---|---|
| Lee et al. 2018 | 8-week randomized double-blind placebo-controlled trial | 100 enrolled; 82 analyzed | Rural Development Administration cooperative research program | NK-cell activity, cytokines, and immunoglobulins | NK-cell activity increased, but IFN-γ and IgG1 were not significant and infection incidence was not assessed. | Key |
| Jang et al. 2021 | Phenotypic and genomic strain-safety assessment | JW15 and comparator strains | Rural Development Administration | Antibiotic resistance, hemolysis, toxic metabolites, and virulence genes | Supports candidate-probiotic safety characterization, not clinical immune efficacy. | Safety only |
Receipt — 4 References
All 4 cited sources were verified for existence at the original page (as of 2026-07-17).
Final verification and publication gate: Codex · Evidence date: 2026-07-17 · Corrections: none
Cite this verdict
[Chamgap] Weissella cibaria JW15 x enhanced immune function and defense against infection — Evidence Grade C·47. 4 cited sources checked. Source: https://chamgap.com/en/verdicts/immunity/weissella-cibaria-jw15-immunity-infection-defense/ · CC BY 4.0CC BY 4.0 — free to use with attribution; do not distort grades, numbers, or verdict meaning.
What this document does and does not do
Chamgap is an information source. It reports what research has and has not confirmed; it does not tell readers what to take or buy. That decision belongs to readers and, when needed, medical or legal professionals. This verdict reflects literature available up to the search date and may change as new research appears. Nothing here is medical advice.