New Study Links Gut Bacteria to Multiple Sclerosis
The Breakthrough Study
In a powerful twin study, researchers analyzed identical twins where one twin has MS and the other doesn’t — allowing them to isolate differences not caused by genetics or early environment. They then transplanted the gut bacteria from those twins into lab mice genetically predisposed to develop MS-like symptoms. The mice who received gut bacteria from the twin with MS developed neurologic symptoms far more often than those who received bacteria from the healthy twin.
Two specific gut bacteria were flagged: Lachnoclostridium and Eisenbergiella tayi — present in higher levels in MS-affected twins and capable of triggering MS-like disease in mice. This is one of the most compelling lines of evidence showing that gut microbes may not just correlate with MS — they may actually cause or worsen it.
At the University of Iowa, the Mangalam Lab uncovered that a low ratio of Bifidobacterium to Akkermansia in the gut correlates with greater MS severity. Transferring that microbiome to mice caused inflammation and worsened disease — suggesting shifts in microbial balance may drive progression, not just reflect it.
What This Means (And Isn’t Saying)
This doesn’t mean your gut is 100% responsible for MS, or that adjusting gut bacteria alone is a cure. MS is complex, involving genes, immune factors, infections, vitamin D status, and more. But these studies suggest gut health may be a key therapeutic target — one that could revolutionize how we think about MS treatment and prevention.
How Gut Bacteria Could Impact MS (Simplified Biology)
Immune activation via gut-brain communication
The gut–brain axis is a two-way communication channel that includes the immune system, nerves (like the vagus nerve), and hormones. Gut bacteria help regulate immune balance. When that balance is off, pro-inflammatory T-cells (like Th17) may accelerate autoimmunity in the brain.Leaky gut and immune overreaction
Pathogenic bacteria can erode the gut lining, making it “leaky.” This allows inflammatory molecules into circulation, disturbing immune regulation and potentially attacking brain tissue.Microbial metabolites and immune signaling
Beneficial bacteria produce short-chain fatty acids (SCFAs), like butyrate, which help calm inflammation and support blood-brain barrier integrity. An imbalance can lead to decreased SCFAs and unchecked immune activity.
A Functional Medicine Roadmap for Gut-Targeted Support in MS
While the science evolves, here’s an evidence-aligned, practical plan you can use — ideally in partnership with a knowledgeable healthcare provider familiar with MS:
Phase 1: Stabilize + Rebalance
Anti-inflammatory diet: Focus on fiber-rich, prebiotic foods (if tolerated), wild fish, olive oil, and plenty of colorful vegetables.
Probiotic/prebiotic support: Choose well-researched strains like Bifidobacterium (e.g., B. infantis) and Lactobacillus.
Gut lining repair: Use L-glutamine, zinc carnosine, and immunoglobulins (SBI) to help heal permeability and improve immune tolerance.
Phase 2: Modulate Gut-Immune Interaction
Targeted microbial shifts: Work with a practitioner to evaluate gut testing (like comprehensive stool panels) and adjust with specific targeted supplements or foods.
Support SCFA production: If diet alone isn’t enough, consider high-quality butyrate supplements or specialized prebiotic blends.
Phase 3: Monitor & Maintain
Track symptom patterns and possible relapses in relation to diet, stress, and gut shifts.
Consider fecal microbiota transplant (FMT) — still experimental in MS but under study.
Explore helminthic therapy (with medical guidance) — early-phase trials show promise in immune modulation for autoimmune disorders like MS.
I am only suggesting these things as possibilities that you should absolutely research yourself and ask a trusted practitioner who is working with your specific case before diving into these things.
Why This Is Hopeful
Gut-focused interventions may favor treatment with fewer side effects than systemic immunosuppressants.
Dietary and lifestyle changes empower agency — not only symptom management but potentially influencing disease progression.
Microbiome-based biomarkers (like the Bifidobacterium:Akkermansia ratio) could one day guide personalized therapies.
Bottom line: While MS has many roots, the gut may play a surprisingly central role — and we now have some strong proof that certain gut microbes aren't just markers of disease, but may be part of its cause. As research deepens, this opens doors to gentle, precision healing strategies rooted in diet, gut health, and immune balance.
"All disease begins in the gut," - Hippocrates (c. 460 BCE - c. 375 BCE)
References
Yoon Hongsup, et al. “Multiple sclerosis and gut microbiota: Lachnospiraceae from the ileum of MS twins trigger MS-like disease in germfree transgenic mice — An unbiased functional study.” Proceedings of the National Academy of Sciences of the United States of America (PNAS), May 6, 2025;122(18):e2419689122. DOI: 10.1073/pnas.2419689122 PubMed
Ghimire Sudeep, et al. “Specific microbial ratio in the gut microbiome is associated with multiple sclerosis and disease severity.” Proceedings of the National Academy of Sciences of the United States of America (PNAS), March 2025. DOI: 10.1073/pnas.2413953122 PubMedPNAS
“Mangalam Lab’s research uncovering a key link between gut microbiota and multiple sclerosis (MS).” University of Iowa, Department of Pathology News, March 26, 2025.