What’s the Latest in Prebiotic Research? – April 2023 Edition
Consumption of Solnul™ Resistant Potato Starch Produces a Prebiotic Effect in a Randomized, Placebo-Controlled Clinical Trial
While resistant starch’s prebiotic effects are well-characterized at high doses (i.e., 15-30 g/day), its effects at lower doses (i.e., <10 g/day) are yet to be evaluated. This three-arm, parallel, randomized, double-blind, placebo-controlled clinical trial assessed the effects of Solnul™ resistant potato starch (RPS) on the abundance of beneficial bacterial populations and stool consistency in healthy adults. Seventy-five participants received either 3.5 g or 7 g per day of RPS, or the placebo, for 4 weeks. The study explored the effects of RPS on the relative abundance of Bifidobacterium and Akkermansia, as well as scores of bowel movement consistency. Participants consuming 3.5 g/day of RPS experienced a significant increase in the relative abundance of both bacterial strains compared to the placebo. RPS at 3.5 g significantly reduced the number of diarrhea- and constipation-associated bowel movements compared to the placebo. The 7 g dose of RPS had a comparative effect to the 3.5 g dose. As such, this study is the first to demonstrate the prebiotic effects of low-dose RPS on beneficial bacteria and bowel movements.
- The prebiotic effect of resistant starch has been demonstrated at 15-30 g/day, but not at doses lower than 10 g/day.
- This study is the first to demonstrate the effects of small doses of RPS on the abundance of beneficial bacteria and stool consistency in healthy adults.
- Solnul™, an unmodified resistant potato starch, exhibits prebiotic effects at 3.5 g and 7 g as demonstrated by an increased abundance of Bifidobacterium and Akkermansia and reduced diarrhea- and constipation-associated bowel movements over a 4-week period.
Access to the study: https://www.mdpi.com/2072-6643/15/7/1582
Reference: Bush, J. R., Baisley, J., Harding, S. V., & Alfa, M. J. (2023). Consumption of SolnulTM Resistant Potato Starch Produces a Prebiotic Effect in a Randomized, Placebo-Controlled Clinical Trial. Nutrients, 15(7), 1582. https://doi.org/10.3390/nu15071582
Effects of a high-prebiotic diet versus probiotic supplements versus synbiotics on adult mental health: The “Gut Feelings” randomised controlled trial
Increasing research, including preclinical and clinical trials, has provided evidence of the “microbiota-gut-brain axis” as a bidirectional communication channel between the nervous system and the gut microbiota. This 8-week, 2×2 factorial, randomized, placebo-controlled, superiority trial studied 119 non-clinical adults with moderate psychological distress and low prebiotic intake (<3 g fiber/day). Participants were randomized to one of the four interventions, which involved 1) probiotic group, 2) prebiotic group, 3) synbiotic group, and 4) placebo group. The probiotic group received the probiotic supplement in addition to their usual diet; the prebiotic group received a high-prebiotic diet and the placebo supplement; the synbiotic group got the probiotic supplement and the high-prebiotic diet; and the placebo group received the placebo supplement and their usual diet. The primary outcome included the assessment of total mood disturbance (TMD) from baseline to 8 weeks while the secondary outcomes included depression, stress, sleep, and well-being measures. It was observed that the high-prebiotic diet reduced TMD relative to the placebo at 8 weeks of treatment, with no evidence of symptom betterment with either the probiotic or synbiotic treatments. Anxiety, stress, and sleep were also improved in response to the high-prebiotic diet, while the probiotic intervention had a tentative progress on well-being. This study provides evidence that high-prebiotic dietary intervention may improve anxiety, stress, sleep, and mood in adults with moderate psychological distress and low prebiotic intake, with no notable benefits with either the synbiotic or probiotic interventions, although further research may be necessary.
- The gut-brain axis is a bidirectional communication channel between the nervous system and gut microbiota.
- This study is the first RCT to examine the mental health outcomes of high-prebiotic dietary intake, a probiotic supplement, and the synbiotic combination of both.
- Eight weeks of high-prebiotic dietary intervention may improve self-reported mood disturbance, stress, anxiety, and sleep in non-clinical adults.
- Confirmatory studies in both non-clinical and clinical populations are needed.
Access to the study: https://pubmed.ncbi.nlm.nih.gov/36815026/
Reference: Freijy, T. M., Cribb, L., Oliver, G., Metri, N. J., Opie, R. S., Jacka, F. N., Hawrelak, J. A., Rucklidge, J. J., Ng, C. H., & Sarris, J. (2023). Effects of a high-prebiotic diet versus probiotic supplements versus synbiotics on adult mental health: The “Gut Feelings” randomised controlled trial. Frontiers in neuroscience, 16, 1097278. https://doi.org/10.3389/fnins.2022.1097278
Effects of a Synbiotic on Plasma Immune Activity Markers and Short-Chain Fatty Acids in Children and Adults with ADHD-A Randomized Controlled Trial
Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder with onset in childhood, affecting about 5% of children and adolescents and 3% of adults worldwide. Previous studies have revealed an altered gut microbiome in ADHD patients without confirming specific ADHD-associated gut bacterial taxa. This 9-week randomized, double-blind, placebo-controlled parallel trial aimed to explore the effects of a synbiotic formulation, Synbiotic 2000, on the plasma concentrations of immune-activity markers and short-chain fatty acids (SCFAs) in children and adults with ADHD. ADHD patients (n=182) aged 5-55 years old completed the intervention receiving either the Synbiotic 2000 or placebo (maltodextrin) with matching healthy adults (n=57). Synbiotic 2000 consisted of lyophilized 4 x 1011 CFU of Pediococcus pentosaceus 5-33:3/16:1, Lactobacillus casei ssp paracasei F19, Lactobacillus plantarum 2362, and 2.5 g of each beta-glucan, inulin, pectin, and resistant starch per dose. The results showed a higher than typical level of pro-inflammatory markers including soluble intercellular cell adhesion molecule-1 (sICAM-1) and soluble vascular cell adhesion molecule-1 (sVCAM-1) and lower SCFAs in plasma in individuals with ADHD, especially children on medication. Treatment with Synbiotic 2000 reduced levels of some pro-inflammatory markers compared to placebo and increased propionic acid levels in children with ADHD receiving medication. Further studies to determine the benefits of synbiotic intake on inflammation in ADHD patients are necessary.
- ADHD is a common neurodevelopmental disorder that develops in childhood and affects 5% of children and adolescents and 3% of adults globally.
- An altered gut microbiome has previously been observed in ADHD patients.
- This study explored the effects of a synbiotic formulation, Synbiotic 2000, on the plasma levels of immune activity markers and SCFAs in children and adults with ADHD.
- Synbiotic 2000 may be effective in reducing some pro-inflammatory markers and increasing propionic acid levels in children with ADHD.
Access the study: https://pubmed.ncbi.nlm.nih.gov/36904292/
Reference: Yang, L. L., Stiernborg, M., Skott, E., Xu, J., Wu, Y., Landberg, R., Arefin, S., Kublickiene, K., Millischer, V., Nilsson, I. A. K., Schalling, M., Giacobini, M., & Lavebratt, C. (2023). Effects of a Synbiotic on Plasma Immune Activity Markers and Short-Chain Fatty Acids in Children and Adults with ADHD-A Randomized Controlled Trial. Nutrients, 15(5), 1293. https://doi.org/10.3390/nu15051293
Effect of Synbiotics in Reducing the Systemic Inflammatory Response and Septic Complications in Moderately Severe and Severe Acute Pancreatitis: A Prospective Parallel-Arm Double-Blind Randomized Trial
Acute pancreatitis is characterized by pancreatic inflammation, causing significant morbidity and mortality when progression from benign to fulminant course leads to systemic inflammatory response syndrome (SIRS) and multiorgan dysfunction. As such, reducing the extent of inflammatory response and preventing organ damage and sepsis are the main goals of treatment. This prospective, parallel, randomized, double-blind, placebo-controlled, superiority trial evaluated the efficacy of synbiotics in reducing the systemic inflammatory response and septic complications in moderately severe and severe acute pancreatitis. Eighty-six patients were randomly assigned to the synbiotic arm to receive 1 g of a synbiotic containing both pre- (Streptococcus faecalis, Clostridium butyricum, and Bacillus mesentricus) and probiotics (Lactobacillus sporogenes) or placebo (control group) twice daily for 14 days. No significant difference in septic complications or inflammatory markers was observed, except for a significant reduction in the total leucocyte and neutrophil counts in the first seven days of synbiotic supplementation. A significant reduction was also observed in the length of hospitalization and bacteraemia, but not in non-septic morbidity or length of ICU stay. Lastly, the need for intervention and mortality was comparable. This study showed a limited impact of synbiotics on the reduction of septic complications in patients with moderately severe and severe acute pancreatitis, with significance only noted for a reduction in the length of hospitalization.
- Acute pancreatitis is a serious condition leading to significant morbidity and mortality.
- Limited trials have explored the efficacy of synbiotics in the prevention of septic complications in acute pancreatitis.
- The synbiotic supplement used in the study caused a significant reduction in bacteraemia and length of hospitalization when compared to the placebo.
- Larger RCTs are needed to draw concrete interpretations of the benefits of synbiotic supplementation in acute pancreatitis.
Access the study: https://pubmed.ncbi.nlm.nih.gov/35857241/
Reference: Rohith, G., Sureshkumar, S., Anandhi, A., Kate, V., Rajesh, B. S., Abdulbasith, K. M., Nanda, N., Palanivel, C., & Vijayakumar, C. (2023). Effect of Synbiotics in Reducing the Systemic Inflammatory Response and Septic Complications in Moderately Severe and Severe Acute Pancreatitis: A Prospective Parallel-Arm Double-Blind Randomized Trial. Digestive diseases and sciences, 68(3), 969–977. https://doi.org/10.1007/s10620-022-07618-1