The gut-brain axis is a complex bidirectional communication system linking the enteric and central nervous systems through neural, immune, endocrine, and microbial pathways. Disruption of this axis has been implicated in a wide range of health conditions, including gastrointestinal disorders, mental health disturbances, and metabolic dysregulation. Natural strategies such as psychobiotics, exercise, sleep hygiene, and stress reduction have been explored as methods to enhance this axis. However, an important holistic intervention—grounding, or earthing—has been largely overlooked. Grounding refers to direct physical contact with the Earth’s surface electrons, which immediately influences vagal tone, reduces inflammation, regulates circadian rhythms, and improves mood and digestive function. Because grounding simultaneously targets brain, autonomic, and digestive pathways, it may be uniquely suited to support and heal the gut-brain axis. This review synthesizes the growing medical evidence on how grounding affects vagal regulation, inflammation, emotional health, microbiome signaling, and digestive motility, and makes a case for grounding as a powerful, under-recognized tool in gut-brain axis restoration.