Every day, you breathe in the gas you made.
Sulfur gas made in the gut circulates through breath and bloodstream. The problem is that this gas is toxic.
Mitochondrial toxicity
These gases carry cellular-respiration toxicity in the same class as cyanide. When cellular energy production is suppressed, it leads to chronic fatigue and brain fog.
Limbic disturbance
Re-inhaling the gas at low dose every day disturbs the limbic system that regulates emotion — anxiety, obsession, irritability, unreality.
If tests say "nothing wrong" but anxiety, mental fog, and fatigue persist, it is worth suspecting not only a psychological cause but the gas you produce.
Anxiety has its own gas.
| Mental symptom | Implicated bacteria | Gas |
|---|---|---|
| Anxiety disorder | Fusobacterium + E. coli | methyl mercaptan |
| Depression · bipolar | Eggerthella | hydrogen sulfide |
A pattern of methyl mercaptan detected in "anxious, restless patients with bloating" — the same organism (Fusobacterium) is implicated in bad breath, anxiety, and colorectal cancer.
A chemical made in the gut touches the brain directly.
The "gut-brain axis" is not an abstract figure of speech — it is a real route by which a measurable gas reaches the brain and emotional centers. That is why digestive symptoms and mental symptoms so often come together.
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The English-language writing on breath gases, the limbic system, and the gut origins of mood lives on Substack.
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