Making Migraine Easier to Stomach: The Role of the Gut Brain Immune Axis in Headache Disorders.

Headache disorders place a significant burden on the healthcare system, with this being the leading cause of disability in those under 50 years. Novel studies have interrogated the relationship between headache disorders and gastrointestinal dysfunction, suggesting a link between the gut-brain-immune (GBI) axis and headache pathogenesis. Although the exact mechanisms driving the complex relationship between the GBI-axis and headache disorders remain unclear, there is a growing appreciation that a healthy and diverse microbiome is necessary for optimal brain health. This review article investigates the role of the GBI-axis in dietary triggers of headache disorders and the evidence indicating that diet can be used to alleviate headache severity and frequency. We then synthesized the relationship between the GBI-axis and post-traumatic headache. Finally, we highlight the scarcity of literature regarding paediatric headache disorders, and the role that the GBI-axis plays in mediating the relationship between sex-hormones and headache disorders. There is potential for novel therapeutic targets for headache disorders if we increase understanding of the GBI-axis in their etiology, pathogenesis, and recovery.