Fructooligosaccharide supplements and the gut in 11 men
What it found
In 11 Japanese men, fructooligosaccharide supplements increased Bifidobacterium in feces, but fructose piled up in the feces of only some of them.
Fecal IgA tended to rise, and blood monocytes fell during supplementation.
What they found
Studies in people
Bifidobacterium increased
The number of Bifidobacterium in feces rose significantly during fructooligosaccharide supplementation. The total number of fecal bacteria did not change significantly across the group.
Fructose in some feces
Three of the 11 men had clearly more fructose in their feces during the fructooligosaccharide phase. The other participants did not show this rise.
Fructose metabolism genes
The men who accumulated fructose in their feces had gut microbiomes almost lacking genes for enzymes that break down fructose. Those who did not accumulate fructose had more of these genes.
Fecal IgA
Fecal IgA tended to increase during fructooligosaccharide intake in some individuals, but the change was not significant across the group.
Blood monocytes
The number of monocytes in blood was significantly lower during the fructooligosaccharide phase than before it, and stayed lower in the post phase. Other blood immune cell subsets mostly showed no significant differences.
Microbial diversity
A measure of fecal microbial diversity was significantly lower during fructooligosaccharide intake than before or after. The authors call this reduction surprising.
What the authors conclude
“Since the study was conducted with only 11 male participants, the results cannot be generalized, and further studies are necessary with a larger sample size, and the inclusion of females in future research, to obtain more comprehensive conclusions.”
Also in their conclusions
- They conclude that there is large inter-individual variability in the gut ecosystem and its response to fructooligosaccharide supplementation.
- They suggest that differences in the gene expression of enzymes involved in fructose metabolism contribute to individual differences in fructose breakdown after fructooligosaccharide intake.
- They state that because the study had only 11 male participants, the results cannot be generalized, and further studies with a larger sample size and including females are necessary.
How it was done
Most findings on fructooligosaccharide supplementation came from animal studies, and results in people were limited. The authors wanted to test whether its effects on the gut ecosystem and health benefits vary between individuals.
Eleven Japanese males aged 30 to 50 took 12 g of a fructooligosaccharide syrup daily for four weeks, after a two-week baseline and followed by a three-week post phase. Feces and blood were collected twice at each of the three phases.
What it can’t tell you
- The study was small, with only 11 men, so the results may not apply to other people.
- It cannot show whether the same changes would happen in women or in people of other ages.
- It cannot show the long-term effects of fructooligosaccharide supplementation, since the intervention lasted only four weeks.
Who paid
- Funding
- Funded by Japan Aerospace Exploration Agency (from the PubMed record).
- Conflicts
- The authors declare no conflict of interest.
- Authors work at
- Laboratory for Intestinal Ecosystem, Japan; Yokohama City University, Japan; Kagawa Nutrition University, Japan
The paper
- Title
- Integrated Multi-Omics Analysis Reveals Differential Effects of Fructo-Oligosaccharides (FOS) Supplementation on the Human Gut Ecosystem
- Type
- Study
- Evidence
- Studies in people
- Summarised from
- Full text
- Cite
- Kato T, Kagawa M, Suda W, et al (2022). Integrated Multi-Omics Analysis Reveals Differential Effects of Fructo-Oligosaccharides (FOS) Supplementation on the Human Gut Ecosystem. International journal of molecular sciences. doi:10.3390/ijms231911728Free full textPubMed 36233028DOI
Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error