Probiotics and gut
What 4 graded rows on probiotics agree on for gut, and where they differ. Counted side by side, never averaged.
Consensus finder Rows from the Probiotics page, reviewed Oct 21, 2026 How it decides
What the rows agree on
Each block and row is one graded row from the Probiotics page, with its PubMed record.
Your question
Probiotics and gut
4 rows · 7,886 peopleSplit. 2 rows found an improvement and 2 found no difference.
- AGrade A× 1
- BGrade B× 1
- ∅No effect× 2
- Rows
- 4
- Trials
- 4
- At least: a review without a trial count
- People
- 7,886
- Pooled reviews may count some twice
Where they differ
From the rowsThe best-graded row, grade A, is a meta-analysis of 4,780 people (2015) and found an improvement. 2 rows are graded No effect, our grade for adequately powered trials that found no effect.
The 2 rows that found an improvement were larger: a median of 3,044 people, against a median of 899 people for the 2 rows that found no difference.
The 2 rows that found an improvement are pooled reviews of several trials; the 2 rows that found no difference are single studies.
The 2 rows that found no difference are newer (2018) than the 2 rows that found an improvement (2015).
The rows
2 improved · 2 no difference- AGrade ADiarrhea risk during antibiotic treatment · Improved
Meta-analysis · n 4,780 · 2015 · Children and adults taking antibiotics in 21 RCTs
Various doses (no clear dose-response per ODS) · Not stated in the abstract
Antibiotic-associated diarrhea fell from 18.7% to 8.5% (RR 0.47; number needed to treat 10): in children from 20.9% to 8.8%, in adults from 17.4% to 8.2%. C. difficile-associated diarrhea fell significantly in children only.
- BGrade BDiarrhea risk during antibiotic treatment · Improved
Meta-analysis · n 1,308 · 2015 · Children and adults taking antibiotics in 11 RCTs
4 x 10^8 to 12 x 10^10 CFU (per ODS) · 10 days to 3 months (per ODS)
Antibiotic-associated diarrhea fell from 22.4% to 12.3% (RR 0.49; low quality of evidence). Separately, the reduction was significant in children (5 RCTs, n=445) but not in adults (6 RCTs, n=863), except in a subset on H. pylori eradication therapy.
- ∅No effectModerate-to-severe illness and diarrhea duration in children with acute stomach illness · No difference
RCT · n 971 · 2018 · Children 3 months to 4 years with acute gastroenteritis at 10 US pediatric emergency departments
1 x 10^10 CFU twice daily · 5 days
Moderate-to-severe gastroenteritis within 14 days: 11.8% with LGG vs 12.6% with placebo (RR 0.96). No differences in diarrhea duration (median 49.7 vs 50.9 hours), vomiting, day-care absence or household spread.
- ∅No effectModerate-to-severe illness and diarrhea duration in children with acute stomach illness · No difference
RCT · n 827 · 2018 · Children 3 to 48 months with gastroenteritis at 6 Canadian pediatric emergency departments
4.0 x 10^9 CFU twice daily · 5 days
Moderate-to-severe gastroenteritis within 14 days: 26.1% with the probiotic vs 24.7% with placebo (odds ratio 1.06). No differences in diarrhea or vomiting duration, unscheduled visits or adverse events.