Xanthan gum breakdown by human gut bacteria
What it found
Certain gut bacteria can break down xanthan gum, and this ability is common in people from industrialized countries.
In mice with human gut microbes, xanthan gum helped these bacteria grow.
What they found
Studies in people
Bacteria that break down xanthan gum
About half of the cultures from 60 adults grew on xanthan gum and made it less thick. A single uncultured bacterium in the Ruminococcaceae family was present in all these cultures.
Presence in different populations
The Ruminococcaceae xanthan-degrading genes were found in all industrialized populations sampled, but not in the non-industrialized populations tested.
Animal and lab studies
Enzymes for xanthan gum breakdown
The Ruminococcaceae bacterium makes enzymes that cut the xanthan gum backbone into smaller pieces. Another gut bacterium, Bacteroides intestinalis, then uses these pieces for growth.
Xanthan gum in mice
In germfree mice given human gut microbes, feeding xanthan gum increased the levels of the Ruminococcaceae bacterium and helped B. intestinalis colonize.
What the authors conclude
“Our work demonstrates the existence of a potential xanthan gum food chain involving at least two members of different phyla of gut bacteria and provides an initial framework for understanding how widespread consumption of a recently introduced food additive influences human microbiomes.”
Also in their conclusions
- They conclude that xanthan gum can drive expansion of specific gut bacteria in industrialized human microbiomes.
- They say that human studies are required to definitively test whether xanthan gum changes the human microbiome.
- They suggest that the abrupt introduction of a new dietary component may drive changes in microbiome ecology with potentially broad impacts.
How it was done
The authors wanted to understand what happens to xanthan gum in the digestive tract, because little was known about how it interacts with gut bacteria.
They studied gut bacteria from 80 adults, then 60 more, and grew them on xanthan gum in the lab. They also fed xanthan gum to germfree mice colonized with human gut microbes.
What it can’t tell you
- This study cannot show whether these changes in gut bacteria affect human health.
- The mouse results may not apply to people.
- The study cannot prove that xanthan gum caused the differences seen between industrialized and non-industrialized populations.
Who paid
- Funding
- Funded by NIDDK NIH HHS; NCATS NIH HHS (from the PubMed record).
- Authors work at
- University of Michigan, USA; Norwegian University of Life Sciences, Norway; DOE Joint Genome Institute, USA
The paper
- Title
- Mechanistic insights into consumption of the food additive xanthan gum by the human gut microbiota
- Type
- Study
- Evidence
- Studies in people · animals · lab
- Summarised from
- Full text
- Cite
- Ostrowski MP, La Rosa SL, Kunath BJ, et al (2022). Mechanistic insights into consumption of the food additive xanthan gum by the human gut microbiota. Nature microbiology. doi:10.1038/s41564-022-01093-0Free full textPubMed 35365790DOI
Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error