Candida, Clostridia, and the Gut–Brain Axis: Effects on Mood, Brain Fog, and Mental Health
The gut is home to trillions of microorganisms that play a critical role not only in digestion, but also in brain health and mental well-being. Through the gut–brain axis—a complex communication network linking the gastrointestinal tract and the nervous system—imbalances in gut microbes can influence inflammation, stress responses, and neurotransmitter pathways.
Candida and Clostridia are two microbial groups that commonly inhabit the gut and are typically harmless. However, when the gut ecosystem is disrupted, particular species may contribute to symptoms such as brain fog, fatigue, mood changes, and anxiety.
This evidence-based review examines the current research on Candida, Clostridia, and the gut–brain connection. It explores underlying biological mechanisms, clinical implications, and safe, science-informed approaches to assessment and treatment—without overstating causation or promoting unnecessary interventions.






