Polydextrose and soluble maize fibre in healthy men
What it found
In 21 healthy men, eating 21 g a day of polydextrose or soluble maize fibre in snack bars increased gas and bloating slightly, but also increased stool bulk and lowered some harmful gut compounds.
The men reported only slight discomfort.
What they found
Studies in people
Gas and bloating
Flatulence and distension were greatest when the men ate either fibre. Reflux was greater with soluble maize fibre than with no fibre. All tolerance scores were low, meaning only slight discomfort.
Harmful gut compounds
Faecal ammonia, 4-methylphenol, indole and branched-chain fatty acids were lower when the men ate either fibre compared with no fibre.
Short-chain fatty acids
Faecal acetate, propionate and butyrate were lower with polydextrose than with soluble maize fibre or no fibre.
Stool bulk and pH
Stool wet weight was greatest with soluble maize fibre. Stool dry weight tended to be greater with polydextrose. Faecal pH was lower with soluble maize fibre than with no fibre.
Bifidobacteria
Bifidobacterium concentrations were higher with soluble maize fibre than with no fibre. Lactobacillus and E. coli did not differ.
What the authors conclude
“These functional fibres appear to be beneficial to gut health while leading to minimal gastrointestinal upset.”
Also in their conclusions
- They say these functional fibres appear to be beneficial to gut health while leading to minimal gastrointestinal upset.
- They suggest that polydextrose and soluble maize fibre may be good candidates as supplemental fibre sources in food products for humans.
How it was done
The authors wanted to see whether these two soluble fibres, which are added to foods, actually behave like traditional dietary fibre in the body and whether they cause gut discomfort.
Twenty-one healthy adult men ate snack bars with either 21 g of polydextrose, 21 g of soluble maize fibre, or no added fibre for 21 days each, in random order. Stool was collected over the last 5 days of each period and the men kept daily records of gut symptoms.
What it can’t tell you
- This was a small study in healthy adult men, so the results may not apply to women, children, or people with gut conditions.
- The study lasted only 21 days per fibre, so it cannot show what happens over longer periods.
Who paid
- Authors work at
- University of Illinois, USA
The paper
- Title
- Digestive physiological outcomes related to polydextrose and soluble maize fibre consumption by healthy adult men
- Type
- Randomised controlled trial
- Evidence
- Studies in people
- Summarised from
- Full text
- Cite
- Boler BM, Serao MC, Bauer LL, et al (2011). Digestive physiological outcomes related to polydextrose and soluble maize fibre consumption by healthy adult men. The British journal of nutrition. doi:10.1017/S0007114511002388Free full textPubMed 21736814DOI
Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error