# Probiotic Anxiety Randomized Trial: What the Evidence Says
Canonical: https://www.migaku.app/guides/probiotic-anxiety-randomized-trial-evidence-review
Category: evidence-review
Summary: Probiotic Anxiety Randomized Trial has 2 source documents in the current Migaku evidence database. The strongest available sources in this first pass are rand
Last reviewed: 2026-06-04
Reviewed by: Migaku Evidence Review
# Probiotic Anxiety Randomized Trial: What the Evidence Says

## Quick Answer

Probiotic Anxiety Randomized Trial has 2 source documents in the current Migaku evidence database. The strongest available sources in this first pass are randomized trial, so conclusions should be framed as evidence-aware guidance rather than medical advice.

## Key Takeaways

- This page is generated only from sources stored in the Migaku evidence knowledge base.
- Current evidence mix: 2 randomized trial.
- Claims should be interpreted with the source type, study design, population, and publication date in mind.
- This article is educational and does not replace care from a qualified clinician.

## Evidence Map

| Source | Evidence type | Level | Date | Identifier |
| --- | --- | ---: | --- | --- |
| Probiotic supplementation for anxiety symptoms in people with Parkinson’s disease: a randomized, double-blind, placebo-controlled trial | randomized trial | 2 | 2026-04-25 | 10.1038/s41531-026-01364-1 |
| A Randomised, Double-Blind, Placebo-Controlled Trial of Probiotic and Postbiotic Strains in Healthy Adults with Self-Reported Anxiety: Effects on Mood, Vitality, Quality of Life and Perceived Stress. | randomized trial | 2 | 2026-04-16 | 10.3390/brainsci16040419 |

## What The Sources Report

- , 3 5 - 6 7, 8 9, 10 11 In addition to its hallmark motor symptoms, Parkinson's disease (PD) is associated with a wide range of non-motor features. [Lam Joyce S. T. (2026); evidence level 2]
- While both medication classes are useful in the appropriate setting, SSRIs can cause sleep disturbances, somnolence, and gastrointestinal issues, and benzodiazepine use increases the risk of cognitive impairment and falls. [Lam Joyce S. T. (2026); evidence level 2]
- Probiotics and postbiotics are gaining attention for their potential to modulate mood and stress via microbiome-related mechanisms, but human evidence remains limited, particularly in non-clinical populations. [Day R (2026); evidence level 2]
- Objectives: We aimed to assess the effects of a two-strain combination of live microorganisms alongside a two-strain combination of heat-treated inactivated microorganisms on outcomes associated with anxiety, mood, perceived stress, and quality of life in healthy adults experiencing mild stress. [Day R (2026); evidence level 2]

## How To Read This Evidence

Evidence level 1 generally reflects systematic reviews or meta-analyses. Level 2 includes randomized trials, guidelines, or public-health guidance. Level 3 usually reflects observational or narrative-review evidence. Level 4 is weaker or early-stage evidence. The level is a sorting aid, not a final quality grade.

## Practical Interpretation

There is trial evidence in the current set, but population and intervention details still matter. For probiotic anxiety randomized trial, the next editorial step is to add more targeted sources and separate strong findings from early or indirect evidence.

## Limits Of This First Pass

This is a small-batch MVP article. It uses the first ingested sources for this topic and should be expanded with more targeted searches, license review, and human editorial checks before being treated as a definitive review.

## References

- Lam Joyce S. T. (2026). Probiotic supplementation for anxiety symptoms in people with Parkinson’s disease: a randomized, double-blind, placebo-controlled trial. DOI: 10.1038/s41531-026-01364-1. PMCID: PMC13125604. PMID: 42034654. License: CC BY 4.0. https://pmc.ncbi.nlm.nih.gov/articles/PMC13125604/
- Day R (2026). A Randomised, Double-Blind, Placebo-Controlled Trial of Probiotic and Postbiotic Strains in Healthy Adults with Self-Reported Anxiety: Effects on Mood, Vitality, Quality of Life and Perceived Stress.. DOI: 10.3390/brainsci16040419. PMCID: PMC13114223. PMID: 42041827. https://pmc.ncbi.nlm.nih.gov/articles/PMC13114223/

## Safety Note

Health information can change, and individual risk depends on medical history, medications, pregnancy status, age, and diagnosis. Talk with a qualified clinician before changing treatment, supplement, or medication routines.