Carboxymethylcellulose and colitis in mice with IBD gut bacteria
What it found
In mice carrying gut bacteria from people with active inflammatory bowel disease, carboxymethylcellulose in drinking water led to more colon inflammation than polysorbate-80 or plain water.
This was an animal study.
What they found
Animal and lab studies
Colon inflammation
Mice given carboxymethylcellulose had higher fecal lipocalin-2, a marker of gut inflammation, than mice given polysorbate-80 or water, starting one week after treatment began and staying higher throughout. Blinded tissue scores also showed more inflammation in the rectum and proximal colon with carboxymethylcellulose.
Inflammatory cytokines
After 28 days, mice given carboxymethylcellulose had higher expression of several inflammatory cytokine genes in the colon than mice given polysorbate-80 or water. The increases were significant for interferon-gamma and interleukin-12p40 compared with water.
Gut bacteria changes
Carboxymethylcellulose did not significantly change the overall bacterial composition, but it significantly decreased a group of viruses called Caudoviricetes (bacteriophages). Polysorbate-80 showed a non-significant trend toward increasing Actinobacteria and Proteobacteria.
Body weight
All mice gained weight over the 28 days, with no difference between groups at any time. Mice given either emulsifier gained slightly less weight than water controls.
Microbial diversity
Microbial diversity was significantly different between polysorbate-80 and carboxymethylcellulose groups, with higher diversity after polysorbate-80 and lower after carboxymethylcellulose.
What the authors conclude
“This study shows that CMC has detrimental effects on colonic immunologic and histologic parameters in ex-GF IL10 −/− mice colonized with pooled IBD fecal transplants, inducing greater inflammation in this model than does P80.”
Also in their conclusions
- They conclude that CMC has detrimental effects on colonic immunologic and histologic parameters in this mouse model, inducing greater inflammation than P80.
- They state that these emulsifiers appear to act via different mechanisms, with P80 directly stimulating both aggressive and protective bacterial subsets, while CMC has no effect on bacterial composition but selectively decreases microbial diversity and bacteriophages.
- They suggest that a low CMC diet might be an alternative exclusion diet for people with Crohn's disease.
How it was done
The authors wanted to compare how two common food emulsifiers, carboxymethylcellulose and polysorbate-80, affect colitis and gut bacteria in an inflammatory setting, since previous work suggested they may act differently.
They transplanted pooled stool from three patients with active inflammatory bowel disease into germ-free mice lacking the IL10 gene. After three days, the mice received 1% carboxymethylcellulose or polysorbate-80 in drinking water, or water alone, for four weeks. Inflammation and gut bacteria were then measured.
What it can’t tell you
- This was a study in mice, so it cannot show what happens in people.
- The mice were genetically modified to lack the IL10 gene and had gut bacteria from people with inflammatory bowel disease, so results may not apply to healthy people or other conditions.
- The study lasted only four weeks, so longer-term effects are unknown.
Who paid
- Funding
- Funded by NIDDK NIH HHS; the US Public Health Service National Institutes of Health (NIH); NIH HHS; the Crohn's & Colitis Foundation (from the PubMed record).
- Conflicts
- The authors declare no conflict of interest relevant to these studies.
- Authors work at
- University of North Carolina at Chapel Hill, USA; Ferdowsi University of Mashhad, Iran; Shimane University, Japan
The paper
- Title
- The Emulsifier Carboxymethylcellulose Induces More Aggressive Colitis in Humanized Mice with Inflammatory Bowel Disease Microbiota Than Polysorbate-80
- Type
- Study
- Evidence
- Animals and lab studies
- Summarised from
- Full text
- Cite
- Rousta E, Oka A, Liu B, et al (2021). The Emulsifier Carboxymethylcellulose Induces More Aggressive Colitis in Humanized Mice with Inflammatory Bowel Disease Microbiota Than Polysorbate-80. Nutrients. doi:10.3390/nu13103565Free full textPubMed 34684567DOI
Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error