What’s the Latest in Prebiotic Research?

April 2025 Edition

A double-blind randomised controlled trial of prebiotic supplementation in children with autism: effects on parental quality of life, child behaviour, gastrointestinal symptoms, and the microbiome

Autism spectrum disorder (ASD) is a neurodevelopmental disorder that affects one in every 44 children. ASD is characterized by impaired social communication and interaction, a narrow interest scope, repetitive behaviors, and unusual sensory responses. The restrictive and repetitive behaviors and sensory dysregulation contribute to increased anxiety and difficulty during social occasions such as mealtimes. Additionally, reports indicate that at least half of children with ASD experience chronic gastrointestinal (GI) symptoms (e.g., constipation, diarrhea, abdominal pain). With a rising interest in the bidirectional gut-brain communication demonstrated in animal models, the effect of modulating the gut microbiome to affect neurological behaviors becomes an intriguing concept. While no distinct microbiome signatures are reported for autism, consistent findings of low microbial diversity and low Bifidobacterium abundance have been reported, although not clear whether it relates to the low dietary diversity seen in ASD or the condition per se. As such, this randomized, double-blind study assessed the effects of a prebiotic intervention versus placebo on behavior, gastrointestinal symptoms, and downstream effects on parental quality of life (pQOL). Thirty-three children with autism (aged 4 to 10 years) with parent dyads were randomly assigned to either 2.4 g/d of galactooligosaccharides (GOS) or maltodextrin (placebo) for six weeks. Stool samples were collected at the baseline and follow-up visits with validated questionnaires to measure social and mealtime behavior change, gastrointestinal symptoms, and pQOL. No significant group differences were reported for behavioral variables and only marginal for GI symptoms. However, Bifidobacterium increased three-fold following prebiotics (p < 0.001) with no change in control. Future trials with larger sample sizes of children experiencing more severe symptoms may be warranted to further explore the effects of prebiotics in children with ASD.

 

Key takeaways:

    • ASD is characterized by challenging behavioral symptoms, with reports of chronic GI symptoms experienced by half of children with this condition.
    • This prebiotic intervention study is the first to investigate the impact of microbiome modulation in ASD children on pQOL.
    • No significant differences were reported in behavioral or GI symptoms associated with ASD, but a significant bifidogenic effect on the microbiome was reported in response to GOS.

 

Access to the study: https://pubmed.ncbi.nlm.nih.gov/38291245/

Reference: Palmer, J. K., van der Pols, J. C., Sullivan, K. A., Staudacher, H. M., & Byrne, R. (2025). A Double-Blind Randomised Controlled Trial of Prebiotic Supplementation in Children with Autism: Effects on Parental Quality of Life, Child Behaviour, Gastrointestinal Symptoms, and the Microbiome. Journal of autism and developmental disorders, 55(3), 775–788. https://doi.org/10.1007/s10803-024-06239-z

Effect of inulin supplementation on fecal and blood metabolome in alcohol use disorder patients: A randomised, controlled dietary intervention

Alcohol use disorder (AUD) is a chronic, relapsing, psychiatric disorder that significantly affects the health of the individual and poses challenges for them, their family, and society. AUD is associated with various neuropsychiatric symptoms, including cognitive impairments and behavioral changes, and it can significantly impact composition and function of the gut microbiota. AUD is further accompanied by nutritional imbalance, including insufficient dietary fiber (DF) intake. Data reports that alcohol consumption clearly leads to alterations in the circulating metabolome (mainly complex lipids and amine-derivatives), with inulin showing potential in modulating the blood metabolome. However, this effect has not been studied in AUD patients. As such, this randomized, double-blinded, placebo-controlled study investigated the effect of inulin (prebiotic DF) versus placebo in patients suffering from AUD during three weeks of alcohol withdrawal to identify microbial-derived metabolites that could be involved in metabolic and behavioral status. Fifty AUD patients were supplemented with inulin or maltodextrin (placebo) for 17 days, with the dose gradually being increased from 4 to 16 g over the intervention period. Fecal microbiota composition, plasma and fecal metabolomics, blood markers of inflammation, hepatic alterations, and psychological assessment were analyzed before and after the intervention. Fecal metabolomics revealed 14 metabolites that were significantly modified by inulin relative to placebo, including an increase in N8-acetylspermidine and a decrease in indole-3-butyric acid, 5-amino valeric acid betaine, and bile acids. Thirteen plasma metabolites also differentiated both treatments with higher levels reported with inulin versus placebo in long-chain fatty acids, medium-chain acylcarnitines, and sphingomyelin species, and reduced 3-methylhistidine. Fecal Lachnoclostridium correlated with 6 of the identified fecal metabolites, whereas plasma lipidic moieties positively correlated with fecal Ruminococcus torques group and Flavonifractor. Interestingly, parameters reflecting liver alterations are inversely correlated with sphingomyelin. Altogether, this study demonstrated that three weeks of inulin supplementation during alcohol withdrawal leads to specific and different changes in the plasma and fecal metabolomics of AUD patients, with some of the gut microbiota-related metabolites being correlated with liver function.

Key takeaways:

    • AUD is characterized by gut microbial dysbiosis and insufficient dietary fiber intake.
    • This study investigated the effects of dietary inulin fiber on the fecal and plasma metabolome in AUD patients during a three-week alcohol withdrawal period.
    • Inulin supplemented group reported specific changes in both plasma and fecal metabolomes of AUD patients, with some metabolites correlating with liver function.
    • Findings suggest potential links between the gut microbiota, metabolomics, and behavioral parameters in AUD patients, indicating a potential benefit from inulin supplementation on metabolic and behavioral outcomes during alcohol withdrawal.

Access to the study: https://pubmed.ncbi.nlm.nih.gov/39864520/

Reference: Amadieu, C., Ahmed, H., Leclercq, S., Koistinen, V., Leyrolle, Q., Stärkel, P., Bindels, L. B., Layé, S., Neyrinck, A. M., Kärkkäinen, O., De Timary, P., Hanhineva, K., & Delzenne, N. M. (2025). Effect of inulin supplementation on fecal and blood metabolome in alcohol use disorder patients: A

randomised, controlled dietary intervention. Clinical nutrition ESPEN, 66, 361–371. https://doi.org/10.1016/j.clnesp.2025.01.046

Indicators of improved emotion behavior in 6-14-year-old children following a 4-week placebo controlled prebiotic supplement intervention at home with a parent

Mental health issues among children and young people are increasing. Prebiotics are psychobiotic compounds that improve emotional well-being and cognition via their gut microbiome modulatory effects. While these compounds have demonstrated their potential to improve health and well-being in adults, the evidence supporting their benefits for children and young people is inconsistent. This randomized, double-blinded, placebo-controlled study investigated the potential benefits of a GOS supplement to enhance emotional well-being among children and young people in a home setting. The primary endpoints were trait anxiety and emotional behavior, while the secondary outcomes were depression levels and cognitive function. Fifty-three healthy children (6–14 years) randomly received 7.5 g/day of the prebiotic product (5.5 g GOS) or placebo (maltodextrin) for 28 days under parental guidance. Baseline (day 0), endline (day 28), and follow-up (day 56) measures were recorded. While the study results showed no statistical significance, some trends were noteworthy. Trait anxiety levels decreased over time in both groups, with a more pronounced decrease observed in the GOS group (p=0.09 at endline, p=0.031 at follow-up). The GOS group also exhibited reduced negative emotional response compared to placebo (p=0.105) and decreased levels of post-trial depression over time (p=0.015). Future studies should implement larger sample sizes to adequately power the trial arms, contributing to a more comprehensive understanding of the potential benefits of prebiotics in this population.

Key takeaways:

    • Cases of mental health issues are increasing among children and young people.
    • This study evaluated the potential of an easily accessible GOS supplement to enhance the well-being of children and young people by targeting emotional behavior, cognition, and nutrient intake.
    • GOS supplementation for 28 days at 5.5 g/day showed encouraging trends in enhancing well-being in children and young people.

 

Access the study: https://pubmed.ncbi.nlm.nih.gov/40025494/

Reference: Johnstone, N., & Cohen Kadosh, K. (2025). Indicators of improved emotion behavior in 6-14-year-old children following a 4-week placebo controlled prebiotic supplement intervention at home with a parent. Nutrition journal, 24(1), 34. https://doi.org/10.1186/s12937-025-01098-5

The effect of prebiotics and probiotics on levels of depression, anxiety, and cognitive function: A meta-analysis of randomized clinical trials

The rising prevalence of anxiety and depressive disorders worldwide is associated with an increase in morbidity and mortality. Besides neurological, environmental, genetic, personality, and inflammatory factors leading to depression, cognitive impairment may be another contributing factor to both anxiety and depression. Recent data suggests that mental health is linked to the health of the gut microbiome. This meta-analysis evaluated the effects of consuming biotics (pre, pro, and syn) on the levels of depression, anxiety, and cognitive function. Four databases, including PubMed, Cochrane Library, Scopus, and Web of Science, as well as ClinicalTrial.gov were searched from their inception to May 5, 2024, to retrieve relevant randomized controlled trials with full-text available in English, published in peer-reviewed journals, and with validated outcome measures for anxiety, depression, and cognitive function. Analysis of the search results showed that biotics consumption significantly reduced anxiety (p=0.0139) and depression (p=0.0335) and significantly improved cognitive function in the study participants. 4295 participants were included in the analyses for anxiety (2194 in the experimental group and 2101 in the control group), 3179 participants for depression (1603 in the experimental group and 1576 in the control group), and 915 participants for cognitive function (470 in the experimental group and 445 in the control group). Although some results were inconsistent, most studies support the efficacy of biotics in reducing symptoms of anxiety and depression and improving cognitive function. Future research may explore optimal conditions for biotic usage and their mechanism of action.

 

Key takeaways:

    • The meta-analysis evaluated the effects of consuming prebiotics and probiotics on depression, anxiety, and cognitive function.
    • MEDLINE (PubMed), Cochrane Library, Scopus, Web of Science, and ClinicalTrials.gov were searched for relevant randomized clinical trials with validated outcomes for depression, anxiety, and cognitive function.
    • With 4295 participants included in the analysis for anxiety, 3179 for depression, and 915 for cognitive function, a significant reduction was observed in anxiety and depression, along with a significant improvement in cognitive function.

 

Access the study: https://pubmed.ncbi.nlm.nih.gov/40038860/

Reference: Zandifar, A., Badrfam, R., Mohammaditabar, M., Kargar, B., Goodarzi, S., Hajialigol, A., Ketabforoush, S., Heidari, A., Fathi, H., Shafiee, A., & Pourjafar, H. (2025). The Effect of Prebiotics and Probiotics on Levels of Depression, Anxiety, and Cognitive Function: A Meta-Analysis of Randomized Clinical Trials. Brain and behavior, 15(3), e70401. https://doi.org/10.1002/brb3.70401