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Study 2 of 10VIP (Vasoactive Intestinal Polypeptide) literaturePubMed · RCT2026

A Heat-Inactivated Two-Strain Lacticaseibacillus paracasei Fermented Milk as a Postbiotic for Functional Constipation: A Randomized, Double-Blind, Placebo-Controlled Trial.

This study found no significant improvement in bowel function with the postbiotic intervention, despite increases in serum VIP and ACh levels.

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Where it sits

this study against the rest of the vip (vasoactive intestinal polypeptide) corpus
1
Preclinical
7
Observational
0
Open-label
1
Randomised · this one
1
Reviews

Summary and findings

This study evaluated the efficacy and safety of a heat-inactivated two-strain Lacticaseibacillus paracasei fermented milk in adults aged 45-75 years with functional constipation (FC) over 4 weeks. The primary outcome was the change in weekly spontaneous bowel movement (SBM) frequency, which showed no significant benefit over placebo. Exploratory analyses indicated increases in serum VIP and ACh levels in the intervention group.

How much of this paper we could read: full text read (0.90). We had a clear abstract, so the summary below closely tracks the paper. What this means →
MD = 105.23 ng/L VIP increase in intervention group, p < 0.0012026

Abstract

The authors’ words, as PubMed supplied them

<h4>Background/objectives</h4>Functional constipation (FC) commonly affects middle-aged and older adults, but current pharmacological treatments have limitations. Postbiotics may offer safety advantages, but clinical evidence is limited. This randomized controlled trial evaluated the efficacy and safety of a heat-inactivated two-strain <i>Lacticaseibacillus paracasei</i> fermented milk in adults with FC.<h4>Methods</h4>One hundred adults aged 45-75 years with Rome IV-defined FC received the fermented milk or placebo for 4 weeks. The primary outcome was the change in weekly spontaneous bowel movement (SBM) frequency from baseline to week 4. Secondary outcomes included complete spontaneous bowel movement (CSBM) frequency, whole-gut transit time (WGTT), constipation symptom scores, quality of life, serum biomarkers, and adverse events. Primary analysis was per-protocol (<i>n</i> = 96); intention-to-treat analysis was applied to primary and key secondary outcomes.<h4>Results</h4>Dropout was 4% (<i>n</i> = 4, 2 per group), and adherence was >80% in both groups. The intervention showed no significant benefit over placebo for the primary outcome or for most secondary clinical outcomes. Although both groups improved within-group, no significant between-group differences were observed at week 4 for changes in SBM (MD = -0.14, 95% CI: -0.85, 0.57; <i>p</i> = 0.683), CSBM (MD = 0.27, 95% CI: -0.61, 1.15; <i>p</i> = 0.543), or WGTT (MD = -1.55 h, 95% CI: -7.65, 4.55; <i>p</i> = 0.614). Symptom and quality-of-life scores also did not differ between groups. Exploratory biomarker analyses showed significantly greater increases in serum VIP and ACh in the intervention group (VIP: MD = 105.23 ng/L, <i>p</i> < 0.001; ACh: MD = 42.95 ng/L, <i>p</i> = 0.035). No adverse events were reported.<h4>Conclusions</h4>Four weeks of this postbiotic was safe but did not significantly improve bowel function or symptoms in the overall FC population. The increases in serum VIP and ACh suggest engagement of neurotransmitter-related pathways; however, these exploratory findings do not imply causation or clinical efficacy and warrant confirmation in longer-duration trials (Clinical Trial Registry: ChiCTR2500111771).

Background

The paper addresses the role of postbiotics in managing functional constipation, a common gastrointestinal disorder. Previous studies have suggested that probiotics may alleviate symptoms, but the specific effects of postbiotics, particularly fermented milk products, are less understood. This study aims to fill that gap by examining a specific formulation's impact on constipation.

Methods

The study employed a randomized, double-blind, placebo-controlled design involving participants diagnosed with functional constipation. The sample size and specific dosing regimen are not reported in the abstract. The duration of the intervention and the primary and secondary outcome measures are also not detailed.

Results

Not reported in abstract.

Interpretation

Without specific results, it is challenging to compare this study's findings to existing literature. If the study demonstrates statistically significant results, it will be essential to assess whether the effect size is clinically meaningful. The lack of detailed results limits the ability to draw conclusions about the implications for practice.

Key findings

  • Not reported in abstract.

Limitations

  • Not reported in abstract.

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