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Dysbiosis

EN: dysbiosis · related terms: microbiome, holobiont, postbiotics
Definition Dysbiosis is a disruption of the balance in the microbiome: a shift in composition, diversity or function that reduces the resilience of the ecosystem. It is not a single disease, but a state that is linked to a wide range of complaints — from digestive problems to a raised inflammatory tone.

In plain language

A healthy microbiome is like a well-functioning team: diverse, balanced and resilient. Dysbiosis is when that team falls out of balance — beneficial species disappear, less desirable ones gain the upper hand, or diversity declines. This can happen after a course of antibiotics, through a one-sided, low-fibre diet, chronic stress, poor sleep or illness. The consequences are often vague and broad: a bloated feeling, irregular stool, fatigue or lowered resistance. Important to know: dysbiosis is not a diagnosis you can simply attach to a complaint — it is a descriptive term for imbalance, and the link with disease is often not yet fully understood. The good news is that the microbiome is resilient: with fibre-rich nutrition, variety and rest, the balance can often restore itself.

The science behind

Dysbiosis is an umbrella term for a deviation from a 'healthy' microbiome profile. Because no single universal healthy composition exists, dysbiosis is usually described functionally: loss of diversity, a decline in beneficial butyrate producers, overgrowth of certain taxa, or a shifted metabolite output.

Loss of butyrate producers. A decline in species such as Faecalibacterium prausnitzii reduces the production of butyrate, with consequences for the gut barrier and inflammation regulation.
Barrier weakening. Fewer short-chain fatty acids and a disrupted mucus layer can increase the permeability of the gut wall ('leaky gut' as a hypothesis).
Inflammatory tone. A shift towards more pro-inflammatory signals (for example via lipopolysaccharides) is associated with low-grade inflammation.
Cause or consequence? In many conditions it is still unclear whether dysbiosis plays a role as cause, consequence or accompanying phenomenon.

Recovery usually focuses on the underlying drivers: fibre-rich and varied nutrition, sensible antibiotic use, sleep and stress regulation. My InnerSelfie describes microbial imbalance as one supportive observation within the broader picture, never as a conclusive explanation. This reading is supportive and observational — not a medical diagnosis.

Related concepts

Where appropriate — support: at signs of imbalance, targeted fibre or strain support can help give beneficial micro-organisms room again. Discover the My Key Nutrients range.

Further reading

Balance and resilience of the microbiome are covered in depth in HOST by Petra Van Gucht. See the books →

Scientific references

• Lee et al. (2024), The human gut microbiome in health and disease.
• Nature, Signal Transduction & Targeted Therapy — microbiota review (s41392-022-00974-4).
Specialized Pro-resolving Mediators — Resolution of Inflammation.

Frequently asked questions

What is dysbiosis?
A disrupted balance in the microbiome: reduced diversity or function that lowers the resilience of the ecosystem.
What causes dysbiosis?
Often a combination: antibiotics, a low-fibre or one-sided diet, chronic stress, poor sleep, illness or ageing.
Can dysbiosis be restored?
The microbiome is resilient. Fibre-rich, varied nutrition, rest and sensible antibiotic use usually support the recovery of balance.
Is dysbiosis a disease?
No. It is a descriptive term for imbalance, not a diagnosis. The link with specific conditions is often not yet fully clarified.