Study · Nutrients · 2024Conflicts declared

Polydextrose and betaine change gut bacteria in mice and colon model

What it found

In obese mice and a lab model of the human colon, polydextrose and betaine changed the mix of gut bacteria and the acids they make.

The colon model did not show a clear change in a gut-made antioxidant called ergothioneine.

What they found

Animal and lab studies

Gut bacteria in mice

In mice on the high-fat diet, polydextrose raised Bifidobacterium and Bacteroidota in feces. Betaine plus polydextrose also raised Bifidobacterium and Bacteroidota compared with the high-fat diet alone.

Enterobacteriaceae in mice

Enterobacteriaceae were higher in the feces of mice given polydextrose than in mice on the high-fat diet alone. Adding betaine to polydextrose lowered Enterobacteriaceae compared with polydextrose alone.

Liver ergothioneine in mice

Ergothioneine in the liver rose 1.6-fold with betaine and 2.0-fold with betaine plus polydextrose compared with the low-fat diet. No significant change was seen in muscle.

Colon model bacteria

In the lab model of the human colon, polydextrose and polydextrose plus betaine increased Faecalibacillus, Neglecta timonensis, and Blautia faecis. They decreased Lachnospiracea incertae sedis.

Colon model acids

Polydextrose and polydextrose plus betaine raised acetic, propionic, and butyric acids in the later parts of the colon model. They lowered 2-methylbutyric acid.

Ergothioneine in colon model

Ergothioneine was found in all colon model samples, ranging from 5 to 91 ng/mL. There was no significant difference in ergothioneine production between any of the groups.

What the authors conclude

“Supplemental betaine and polydextrose alter gut microbiota, as was demonstrated in both obese mice and a simulated human colon model.”
Saarinen MT, Forssten SD, Evans K, et al, 2024

Also in their conclusions

  • They conclude that supplemental betaine and polydextrose alter gut microbiota in both obese mice and a simulated human colon model.
  • They state that the human colonic simulation model was unable to detect a significant change in microbiota-based EGT production and thus could not explain the increase in EGT observed in the liver of betaine-fed mice.
  • They suggest that studies using isotopically labeled precursors with more accurate analytical methods may be needed to confirm EGT production in gut biomes.

How it was done

The authors wanted to understand whether gut bacteria help make ergothioneine, an antioxidant that increased in mouse liver after betaine or polydextrose was added to the diet.

Male mice were fed a high-fat diet for 8 weeks to make them obese, then for 4 more weeks they got the same diet with betaine, polydextrose, or both. A lab model of the human colon was also used, with stool samples from healthy adults, to test the same ingredients over 48 hours.

What it can’t tell you

  • The mouse part cannot show what happens in people.
  • The colon model is a lab setup, not a living human gut, so it cannot show real effects in people.
  • The study cannot show that changes in gut bacteria cause the rise in liver ergothioneine seen in mice.

The paper

Title
Effects of Betaine and Polydextrose on Intestinal Microbiota and Liver Ergothioneine in a High-Fat Diet-Fed Mouse Model and a Human Colonic Simulation Model
Type
Study
Evidence
Animals and lab studies
Summarised from
Full text
Cite
Saarinen MT, Forssten SD, Evans K, et al (2024). Effects of Betaine and Polydextrose on Intestinal Microbiota and Liver Ergothioneine in a High-Fat Diet-Fed Mouse Model and a Human Colonic Simulation Model. Nutrients. doi:10.3390/nu17010109Free full textPubMed 39796547DOI

Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error