Xylooligosaccharides (XOS) and gut bacteria

What 2 graded rows on xylooligosaccharides (xos) agree on for gut bacteria, and where they differ. Counted side by side, never averaged.

Consensus finder Rows from the Xylooligosaccharides (XOS) page, reviewed Oct 21, 2026 How it decides

What the rows agree on

Each block and row is one graded row from the Xylooligosaccharides (XOS) page, with its PubMed record.

Supplement

Xylooligosaccharides (XOS) Choose another

2 rows · 92 people

They agree: both rows found an improvement.

No difference

Improved

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

From the rows

The best-graded row, grade D, is a randomized trial of 60 people (2012) and found an improvement.

The rows run from 32 to 60 people, published from 2012 to 2014: 2 single studies.

2 improved

Grade DGut bacteria and butyrate · Improved
RCT · n 60 · 2012 · Healthy volunteers on a high-fat diet
5 g XOS a day (or 3 g inulin + 1 g XOS) · 4 weeks
XOS alone raised faecal Bifidobacterium and butyrate and lowered acetate and p-cresol; only the inulin-XOS mix lowered blood LPS and inflammatory gene responses.
Row on the Xylooligosaccharides (XOS) page · PubMed 22264499 (opens PubMed)
Grade DGut bifidobacteria · Improved
RCT · n 32 · 2014 · Healthy adults
1.4 or 2.8 g a day · 8 weeks
Bifidobacteria rose in both XOS groups vs placebo, more at 2.8 g; lactobacilli, stool pH and short-chain fatty acids did not change, and XOS caused no significant gut side effects.
Row on the Xylooligosaccharides (XOS) page · PubMed 24513849 (opens PubMed)