Streptococcus salivarius K12 and bad breath

What 2 graded rows on streptococcus salivarius k12 agree on for bad breath, and where they differ. Counted side by side, never averaged.

Consensus finder Rows from the Streptococcus salivarius K12 page, reviewed Oct 21, 2026 How it decides

What the rows agree on

Each block and row is one graded row from the Streptococcus salivarius K12 page, with its PubMed record.

Your question

Ear infections2 Sore throat2 Bad breath2

Supplement

Streptococcus salivarius K12 Choose another

Streptococcus salivarius K12 and bad breath

2 rows · 108 people

Split. 1 row found an improvement and 1 found no difference.

No difference

Improved

Each block is one evidence row, sized by how many people it enrolled, with its grade inside.

Grade D× 1
No effect× 1

Rows: 2
Trials: 2
People: 108

Where they differ

From the rows

Trial sizeWhen published

The best-graded row, grade D, is a randomized trial of 80 people (2026) and found an improvement. 1 row is graded No effect, our grade for adequately powered trials that found no effect.

The row that found an improvement was larger: 80 people, against 28 people for the row that found no difference.

The row that found an improvement is newer (2026) than the row that found no difference (2020).

The rows

1 improved · 1 no difference

Grade DBad breath (volatile sulfur compounds) · Improved
RCT · n 80 · 2026 · Adults with halitosis (four groups: control, K12, tongue brushing, both)
Not stated in the abstract · 4 weeks, plus 4 weeks follow-up
Volatile sulfur compounds fell from baseline with K12, with tongue brushing and with both combined, most with the combination; organoleptic odour scores improved only in the combined group, and tongue coating did not fall with K12 alone.
Row on the Streptococcus salivarius K12 page · PubMed 41604763 (opens PubMed)
No effectBad breath linked to tongue coating · No difference
RCT · n 28 · 2020 · Adults with tongue-coating halitosis who did not scrape the tongue or use antiseptic rinse first (Beijing)
One tablet a day (CFU not stated in the abstract) · 30 days
Odour scores and sulfur compounds fell from baseline in the K12 group, but there were no differences from placebo in odour, sulfur compounds or tongue coating.
Row on the Streptococcus salivarius K12 page · PubMed 32227309 (opens PubMed)

Read onRead the full evidenceThe full evidence chapter on its page, with every outcome and its sources.