Lactitol combined with a probiotic in healthy older people
What it found
Taking lactitol together with a specific probiotic twice daily for two weeks slightly raised stool frequency and boosted certain gut bacteria in healthy older people.
The changes in immune markers were small.
What they found
Studies in people
Stool frequency
People taking the lactitol and probiotic mix had slightly more bowel movements than those taking the sugar placebo. The difference was small because the volunteers already had normal bowel habits.
Gut bacteria levels
The lactitol and probiotic group showed higher amounts of bifidobacteria and the specific probiotic strain in their stool after two weeks. These levels dropped back down once they stopped taking the product.
Short-chain fatty acids
Levels of short-chain fatty acids, which are made by gut bacteria, did not change between the groups. The authors suggest this might be because the amount of lactitol given was lower than in earlier studies.
Immune markers
One immune marker called PGE2 rose slightly in the group taking the lactitol mix compared to the placebo. Another marker changed over time but was similar in both groups. The authors note these shifts were modest because the volunteers were healthy.
Spermidine levels
A compound called spermidine increased in the group taking the lactitol and probiotic mix. The authors suggest this might point to better gut lining health and movement.
What the authors conclude
- They say that taking lactitol together with the probiotic twice daily led to a small improvement in stool frequency without side effects.
- They note that the combination raised levels of certain gut bacteria and some compounds linked to gut lining health.
- The authors suggest these results point to improved gut bacteria balance and gut function in older people.
How it was done
As people age, bowel and immune function often decline, possibly linked to shifts in gut bacteria. The authors wanted to see if combining lactitol with a probiotic could improve these markers in older adults who regularly used common painkillers.
They recruited 51 healthy volunteers over 65 from Finland who took painkillers at least three times a week. For two weeks, participants took either a mix of lactitol and Lactobacillus acidophilus NCFM or a sugar placebo twice daily. Forty-seven people finished the study.
What it can’t tell you
- This trial only lasted two weeks, so it cannot show what happens when people take lactitol and this probiotic over months or years.
- Because lactitol was always given together with a probiotic, this trial alone cannot separate out the effects of lactitol by itself.
- All the volunteers were healthy older adults in Finland who used painkillers, so the results might differ for other populations.
The paper
- Title
- Influence of a combination of Lactobacillus acidophilus NCFM and lactitol on healthy elderly: intestinal and immune parameters
- Type
- Randomised controlled trial
- Evidence
- Studies in people
- Summarised from
- Full text
- Cite
- Ouwehand AC, Tiihonen K, Saarinen M, Putaala H, Rautonen N (2009). Influence of a combination of Lactobacillus acidophilus NCFM and lactitol on healthy elderly: intestinal and immune parameters. The British journal of nutrition. doi:10.1017/S0007114508003097Free full textPubMed 18634707DOI
Summary written 30 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error