Overview
Migraine is a complex neurological disorder characterized by recurrent episodes of moderate-to-severe headache, often unilateral and pulsatile, accompanied by nausea, photophobia, and phonophobia. Affecting over one billion people worldwide, it is the second leading cause of disability globally. The gut brain axis is increasingly implicated in migraine pathophysiology.
Microbiome Associations
Migraine patients show altered gut microbiome composition, with enrichment of nitrate-reducing bacteria — organisms that convert dietary nitrate to nitrite and nitric oxide (NO). Excess NO is a known migraine trigger through vasodilation and CGRP release. Taxa enriched in migraine include certain Streptococcus and Haemophilus species. Depletion of butyrate-producing Faecalibacterium and Roseburia has also been reported, suggesting impaired gut barrier function.
Metal Associations
Magnesium deficiency is one of the most consistent findings in migraine, present in up to 50% of patients during attacks. Magnesium modulates NMDA receptor excitability and serotonin receptor function. Iron metabolism is altered — serum ferritin levels correlate inversely with migraine frequency in some studies. Copper and zinc imbalances have been reported but findings are inconsistent.
Associated Conditions
Migraine shows strong comorbidity with irritable-bowel-syndrome (shared gut-brain axis dysfunction), depression (serotonin pathway overlap), celiac disease (gluten as trigger, shared nutrient malabsorption), and Helicobacter pylori infection. The gut-brain overlap suggests shared microbial and metabolic underpinnings rather than coincidental co-occurrence.
Open Questions
Whether microbiome-targeted interventions (probiotics, dietary modification of nitrate intake) can reduce migraine frequency remains an active area of clinical investigation with preliminary but encouraging results.
Cross-References
- gut brain axis — primary mechanistic framework
- magnesium — deficiency and neuronal excitability
- nitric oxide — microbial nitrate reduction as trigger
- irritable-bowel-syndrome — gut-brain comorbidity