Resistant starch fermented by infant gut bacteria in lab tests
What it found
In lab tests, gut bacteria from infants could break down resistant starch, and this ability increased after babies started solid foods.
The starch also boosted levels of Bifidobacterium and Bacteroides in the weaning samples.
What they found
Animal and lab studies
Fermentation before weaning
In lab tests, stool bacteria from preweaning infants broke down resistant starch, shown by a drop in pH and a rise in short-chain fatty acids. This means the bacteria could ferment the starch even before solids.
Fermentation after weaning
After infants started solid foods, their gut bacteria fermented resistant starch even more, with higher short-chain fatty acid production. The ability to ferment the starch increased with weaning.
Bacterial diversity
In weaning infants, resistant starch increased the variety of gut bacteria (Shannon diversity index) compared to controls. No such increase was seen in preweaning samples.
Helpful bacteria
In weaning samples, resistant starch boosted the numbers of Bifidobacterium and Bacteroides, and increased the ratio of Bacteroidetes to Firmicutes. These changes were not seen in preweaning samples.
Modified starch
A chemically modified resistant starch (HAMSA) had similar effects on gut bacteria as the unmodified one. Both increased Bifidobacterium and Bacteroides in weaning samples.
What the authors conclude
“This study confirms that faecal inocula, whether preweaning or at weaning infants has the capacity to utilise HAMS and HAMSA as a potential substrate.”
Also in their conclusions
- They conclude that infant gut bacteria can ferment resistant starch, and this ability increases after solids are introduced.
- They say resistant starch may work as a prebiotic in infants, but this needs to be tested in real feeding studies.
- They advise that further studies are needed to find a safe dose of resistant starch for babies and children.
How it was done
The authors wanted to see if resistant starch, which acts as a prebiotic in adults, could also be fermented by infant gut bacteria. They thought this might help shape the gut bacteria during a key developmental window.
They collected stool samples from 17 healthy infants before weaning and again within 10 weeks after starting solids. They mixed the samples with resistant starch in lab dishes and measured fermentation products and bacterial changes after 24 hours.
What it can’t tell you
- This was a lab study using stool samples, so it cannot show what happens inside a baby's gut.
- The results cannot prove that eating resistant starch would cause the same bacterial changes or any health benefits in infants.
Who paid
- Conflicts
- The authors declare no conflict of interest
- Authors work at
- Monash University, Australia; Flinders University, Australia; Edith Cowan University, Australia
The paper
- Title
- Resistant Starch is Actively Fermented by Infant Faecal Microbiota and Increases Microbial Diversity
- Type
- Study
- Evidence
- Animals and lab studies
- Summarised from
- Full text
- Cite
- Gopalsamy G, Mortimer E, Greenfield P, Bird AR, Young GP, Christophersen CT (2019). Resistant Starch is Actively Fermented by Infant Faecal Microbiota and Increases Microbial Diversity. Nutrients. doi:10.3390/nu11061345Free full textPubMed 31208010DOI
Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error