This article explores possible relationships between migraine, irritable bowel syndrome (IBS), celiac disease (CD), and gluten sensitivity. These seemingly distinct medical entities curiously share many common epidemiological, psychosocial, and pathophysiological similarities. Considerable evidence is emerging to support a concept that experiencing significant threatening adverse events creates a state of hypervigilance in the nervous system, which associates with exaggerated response to future threats and episodic attacks of migraine and IBS. While this sensitizing response is generally considered to reside in the central nervous system, it may be possible that the initiation resides in the enteric nervous system as well. What appears to link migraine, IBS, and CD is a disease model of a genetically sensitive nervous system transformed into one that is hypervigilant, and that over time can often develop disabling and pervasive disease.