Research

Mixed

Depression and insomnia are associated with specific alterations in gut microbiota composition, including decreased Bacteroidetes and increased Firmicutes/Actinobacteria, suggesting a bidirectional link between mental health and gut ecology.

If you have depression or insomnia, your gut health may be a contributing factor. While not a cure-all, addressing gut health through diet and potentially probiotics may support mental health treatment.

ModerateSupportsMEDIUM confidence
Zheng et al. (85) found that depressed patients had increased relative abundance of Actinobacteria and Firmicutes but decreased abundance of Bacteroidetes... These findings suggest that depression might damage the gut-microbiota equilibrium, reducing the anaerobic population and increasing the number of aerobic inhabitants.
Yuanyuan Li et al. · Frontiers in Psychiatry · 2018

Why this rating

Observational human studies show consistent trends but variability; animal models confirm causality.

Source

The Role of Microbiome in Insomnia, Circadian Disturbance and Depression

Yuanyuan Li et al. · Frontiers in Psychiatry · 2018

DOI 10.3389/fpsyt.2018.00669

narrative_reviewCited 294×
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DOI resolved against Crossref · corpus check 2026-06-10

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