Study · Food & function · 2016Abstract only

Guar gum fiber fermentation differs widely between six people

What it found

In lab tests using stool samples from six people, partially hydrolyzed guar gum produced different amounts of short chain fatty acids and gas from person to person.

One donor's fatty acid levels fell by 24 hours, suggesting faster fermentation.

What they found

Animal and lab studies

Gas production varied

Gas production ranged from 59 to 80 mL per 0.5 g fiber at 12 hours and 85 to 93 mL per 0.5 g fiber at 24 hours across the six donors.

Butyrate levels differed

At 12 hours, butyrate concentrations ranged from 6.99 to 23.84 micromoles per milliliter, and at 24 hours from 8.78 to 22.84 micromoles per milliliter.

Total fatty acids varied

Total short chain fatty acid concentration at 24 hours ranged from 42.85 to 91.17 micromoles per milliliter, a more than 2-fold difference between donors.

Fatty acid ratio

The average short chain fatty acid ratio for the six donors was 30:45:25 for acetate, propionate and butyrate, similar to other fermentable fibers tested in lab systems.

One donor fermented faster

Donor 6 had lower short chain fatty acid concentrations at 24 hours, indicating a quicker fermentation process than the other five donors.

Fatty acids fluctuated

All short chain fatty acids measured fluctuated greatly among the six individuals within 24 hours of analysis.

What the authors conclude

“With over a 2-fold difference in SCFA production, significant differences were found among healthy individuals fecal microflora when exposed to PHGG.”
Carlson J, Esparza J, Swan J, Taussig D, Combs J, Slavin J, 2016

Also in their conclusions

  • They found significant differences among healthy individuals' fecal microflora when exposed to partially hydrolyzed guar gum.
  • They note that short chain fatty acid development in the distal intestine increases metabolizable energy from the diet but varies greatly among people based primarily on the composition and changes of their gut microflora.
  • They state that results of in vitro fermentation analyses are limited by the wide variation found with fecal donor.

How it was done

The authors note that changes in short chain fatty acid production from fermenting dietary fibers in the colon have been widely studied, but few studies look at differences between individuals exposed to the same fiber.

They fermented partially hydrolyzed guar gum in lab tests with fecal samples from six donors aged 23 to 68, and measured gas and short chain fatty acid production at 12 and 24 hours.

What it can’t tell you

  • We summarised it from the abstract only.
  • These are lab tests using stool samples, so they cannot show what happens inside the human gut.
  • The results come from only six donors, so they may not reflect the wider population.
  • The study measured fermentation products, not health effects in people.

The paper

Title
In vitro analysis of partially hydrolyzed guar gum fermentation differences between six individuals
Type
Study
Evidence
Animals and lab studies
Summarised from
Abstract only
Cite
Carlson J, Esparza J, Swan J, Taussig D, Combs J, Slavin J (2016). In vitro analysis of partially hydrolyzed guar gum fermentation differences between six individuals. Food & function. doi:10.1039/c5fo01232ePubMed 26862979DOI

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