# Probiotic Brain Effects May Linger Weeks After You Stop Taking Them

*Probiotic effects on brain health are both transient and sustained for several weeks after discontinuation: a randomised controlled trial.*

- **Evidence Level**: Preliminary
- **Publication Types**: Journal Article
- **Journal**: Communications medicine
- **Sample Size**: 32 healthy older adults (average age 68)
- **Authors**: Hutchinson AN, Brummer RJ, Rode J
- **Published**: 2026-07-28
- **Topics**: probiotics, gut-brain axis, brain health
- **DOI**: https://doi.org/10.1038/s43856-026-01800-6
- **Original Source**: https://pubmed.ncbi.nlm.nih.gov/42521749/

## Summary

In healthy older adults, a probiotic's effects on brain activity and anxiety didn't all vanish once they stopped taking it. Some changes stuck around for 4 to 6 weeks after the last dose. This challenges the assumption that probiotics only work while you take them daily. Note this was a very small study.

## Practical Takeaway

This study suggests probiotic effects on the brain may outlast daily use.

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_Canonical: https://longevity-china.com/en/research/probiotic-brain-effects-may-linger-weeks-after-you-stop-taking-them · Part of Longevity Cities · Updated 2026-07-28_