The Emerging Role of Gut Microbiota in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS): Current Evidence and Potential Therapeutic Applications.
Varesi, Angelica, Deumer, Undine-Sophie, Ananth, Sanjana et al. · Journal of clinical medicine · 2021 · DOI
Quick Summary
Many people with ME/CFS experience stomach and digestive problems alongside their fatigue and pain. This review explores how the bacteria living in our gut might be different in ME/CFS patients and could be contributing to symptoms. The researchers found that people with ME/CFS tend to have fewer types of gut bacteria compared to healthy people, and they discuss how treating the gut microbiome might help reduce ME/CFS symptoms overall.
Why It Matters
This review connects gastrointestinal symptoms—commonly reported but often overlooked—to the biological underpinnings of ME/CFS, opening new therapeutic avenues. Understanding the role of the gut microbiota could lead to targeted interventions that address multiple ME/CFS symptoms simultaneously rather than treating them in isolation.
Observed Findings
- Altered composition and decreased overall diversity of gut microbiota in ME/CFS patients compared to healthy controls
- Gastrointestinal problems are commonly reported in ME/CFS populations, sometimes occurring independently of formal GI diagnoses
- Genetic factors, prior infections, and other environmental influences may contribute to microbiota alterations in ME/CFS
- Dysbiosis may lead to intestinal barrier dysfunction with potential systemic immune and neurological consequences
- Several ME/CFS cases show concurrent or comorbid GI conditions including IBS and Crohn's disease
Inferred Conclusions
- The gut microbiota represents a previously underexplored mechanism linking gastrointestinal symptoms to broader ME/CFS pathophysiology
- Therapeutic interventions targeting the microbiota may offer a holistic approach to alleviating multiple ME/CFS symptoms
- Future research should prioritize longitudinal studies and mechanistic investigations to clarify causal relationships between dysbiosis and ME/CFS
Remaining Questions
- Does dysbiosis precede ME/CFS onset or develop as a consequence of the disease and its associated behaviors (e.g., reduced activity, dietary changes)?
- Which specific microbiota modifications or interventions (probiotics, prebiotics, dietary changes) are most effective for improving ME/CFS symptoms?
- How do genetic predisposition, trigger infections, and other risk factors interact to produce the observed dysbiosis patterns in ME/CFS populations?
- Can microbiota profiling be developed as a diagnostic or prognostic biomarker for ME/CFS?
What This Study Does Not Prove
This systematic review does not establish that dysbiosis causes ME/CFS or prove that microbiota-targeted therapies will effectively treat the condition; it identifies an association and potential mechanisms. The review cannot determine whether altered microbiota are a primary driver, secondary consequence, or incidental finding in ME/CFS. Individual studies included may not have controlled for confounding variables such as diet, medication use, or comorbid conditions.
Topics
Tags
Metadata
- DOI
- 10.3390/jcm10215077
- PMID
- 34768601
- Review status
- Machine draft
- Evidence level
- Established evidence from major reviews, guidelines, or evidence maps
- Last updated
- 7 April 2026