Published in the Journal of Dietary Supplements, the research showed that 12 weeks of supplementation with two Lactiplantibacillus plantarum strains relieved stress, increased the number of bowel movements and improved stool consistency in constipated older adults.
Dr. Maria Rodriguez-Palmero Seuma, medical director at AB-Biotics and co-author of the study, said the research adds to existing evidence that AB-Biotics and Kaneka’s Innerim-branded product supports gastrointestinal (GI) health, immunity and quality of life.
“The findings suggest that this probiotic blend may effectively support both gastrointestinal function and mental well-being in elderly individuals,” she told NutraIngredients.
“Given that the underlying pathophysiology of constipation and its impact on mental health are similar across age groups, it is likely that these benefits could also extend to the broader adult population. However, further studies in diverse cohorts would help confirm the generalizability of these results.”
Study details
The effect of probiotics on constipation is well-researched, with a number of randomized clinical trials showcasing their ability to improve stool frequency and consistency.
However, most studies have been conducted in individuals with chronic constipation, with few studying healthy, older populations.
The researchers from AB-Biotics and Kaneka studied the effects of two strains of L. plantarum (KABP 031 and KABP 032) in group of adults between the ages of 50 and 85 with normal BMI.
“These two strains were originally isolated from the gut of healthy individuals, and the species are commonly present in a balanced gut microbiome,” Dr. Rodriguez-Palmero Seuma said. "In vitro studies have demonstrated that both strains possess promising properties that may support immune modulation and gut barrier function, making them strong candidates for use in a probiotic targeting gastrointestinal health."
To conduct their study, the researchers selected 70 participants who had five or less bowel movements per week, with at least a quarter of bowel movements being type 1 or 2 on the Bristol Stool Scale.
Half were randomized to the probiotic group and half to the control (maltodextrin) for 12 weeks. All participants were advised not to change their diet or exercise regimen and were given a multivitamin and mineral supplement to determine whether the probiotic would increase nutrient absorption.
Both groups were then assessed at the half-way point (42 days) as well as at the end of the supplemental period to identify changes to stool frequency and consistency, as well as gastrointestinal symptoms, nutrient uptake and perceived stress levels.
The gut-brain axis
Compared to the placebo group, participants in the probiotic group saw improvements in stool frequency and constipation after just 42 days, with Bristol Stool Chart scores increasing to over three on average, which is within the healthy range.
Dr. Rodriguez-Palmero Seuma said Innerim may support constipation by producing acetate, which can reinforce the intestinal barrier and limit pathogen invasion, thereby normalizing transit time and microbial composition.
“Its anti-inflammatory properties, including modulation of cytokines and reduction of reactive C-protein levels, may also relieve low-grade inflammation often associated with constipation,” she added. “Plus, Innerim enhances the immune response by activating key immune cells—T-helper, T-suppressor, B lymphocytes, NK cells—and reducing TGF-β1, contributing to a healthier gut environment that supports regular motility."
Levels of perceived stress also improved in the probiotic group, with just 9.4% reporting moderate stress levels compared to 37.9% in the placebo.
The researchers suggested that this improvement is likely due to the probiotic’s ability to influence the gut-brain axis.
“These improvements may be attributed to enhanced bowel habits, as constipation is known to negatively affect both quality of life and psychological well-being,” said Dr. Rodriguez-Palmero Seuma.
The study did not observe any between group differences in nutrient levels, suggesting that the probiotic did not improve the ability of the gastrointestinal tract to absorb vitamins and minerals. However, larger studies in more diverse populations may be needed to see such effects, Dr. Rodriguez-Palmero Seuma noted.
“While no statistically significant differences were observed in this specific population, the investigators suggest that future studies explore this combination in groups with a higher risk of nutritional deficiencies, where the potential impact may be more pronounced,” he said.
Source: Journal of Dietary Supplements. doi: 10.1080/19390211.2025.2507610. "Efficacy of Probiotic Supplementation with Lactiplantibacillus plantarum. Strains on Gastrointestinal Tract Function – A Randomized Controlled Trial." Authors: R. Singh, et al.
