Oligofructose in infant formula and gut bacteria
What it found
Infants fed formula with added oligofructose had a bigger rise in gut bifidobacteria over 8 weeks than infants fed formula without it, and softer stools.
Their hydration stayed normal.
What they found
Studies in people
Bifidobacteria rise
Over 8 weeks, bifidobacteria in stool rose more in the oligofructose group than in the control group. The rise in the oligofructose group was similar to that in breastfed infants.
Other gut bacteria
Changes in Bacteroides, clostridia, Lactobacillus/Enterococcus and Staphylococcus were similar between the two formula groups. There were no differences between either formula group and the breastfed group for any of these bacteria.
Stool softness
At week 8, infants in the oligofructose group had softer stools than the control group, on a 5-point scale from hard to watery. Their stool consistency fell between the control and breastfed groups.
Stool frequency
There was no significant difference in the number of stools per day between the two formula groups. Both formula groups passed fewer stools per day on average than breastfed infants.
Hydration
Doctors assessed hydration as normal for all infants at every check. There was no significant difference between the formula groups in wet diapers per day or in weight at week 8.
Gut inflammation marker
Levels of calprotectin, a marker of gut inflammation, did not change significantly in the oligofructose group compared with the control group. Levels in both formula groups were similar to each other and lower than in breastfed infants.
What the authors conclude
“Infant formula with 3.0 g/L OF promoted bifidobacteria growth and softer stools without adversely affecting stool frequency or hydration.”
Also in their conclusions
- They conclude that adding 3.0 g/L oligofructose to an infant formula increased bifidobacteria over 8 weeks, similar to breastfed infants and more than a control formula.
- They say formula-fed infants receiving oligofructose had softer stools than those on control formula, more like breastfed infants, without more frequent stools or harm to hydration.
- They state that the study supports the safety and tolerability of an oligofructose-containing infant formula, including hydration status.
How it was done
The authors wanted to see whether adding oligofructose to infant formula could make the gut bacteria and stools of formula-fed infants more like those of breastfed infants, and whether it affected hydration.
They randomly assigned 95 formula-fed infants to a control formula or the same formula with 3.0 g/L oligofructose for 8 weeks, and also followed 50 breastfed infants. Stool samples were tested at set times, and parents recorded stool frequency and consistency.
What it can’t tell you
- The study lasted 8 weeks, so it cannot show whether the changes in gut bacteria or stools last longer.
- It cannot show whether these changes lead to fewer infections or other health benefits.
- It cannot show what happens at other doses of oligofructose or in other groups of infants.
Who paid
- Conflicts
- Declaration of Conflicting Interests: The author(s) declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: Susan Wernimont, Robert Northington, Manjiang Yao, and Jodi Bettler are employees of Nestlé Nutrition. Martin Kullen was an employee of Wyeth Nutrition at the time of the study and is currently employed by DuPont Nutrition & Health, Wilmington, Delaware.
The paper
- Title
- Effect of an α-lactalbumin-enriched infant formula supplemented with oligofructose on fecal microbiota, stool characteristics, and hydration status: a randomized, double-blind, controlled trial
- Type
- Randomised controlled trial
- Evidence
- Studies in people
- Summarised from
- Full text
- Cite
- Wernimont S, Northington R, Kullen MJ, Yao M, Bettler J (2015). Effect of an α-lactalbumin-enriched infant formula supplemented with oligofructose on fecal microbiota, stool characteristics, and hydration status: a randomized, double-blind, controlled trial. Clinical pediatrics. doi:10.1177/0009922814553433Free full textPubMed 25297064DOI
Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error