What is the gut often referred to as, due to its complex nervous system?

The gut is commonly referred to as the "second brain" because it houses a complex network of neurons known as the enteric nervous system. This system contains approximately 100 million neurons, which is more than either the spinal cord or peripheral nervous system. The enteric nervous system operates independently but communicates with the central nervous system (the brain) and plays a crucial role in managing digestive processes, reflecting how closely the gut and brain are interconnected.

This concept highlights the significant influence that gut health can have on overall physical and emotional well-being. The "second brain" is also implicated in processes such as mood regulation, as neurotransmitters like serotonin are produced in the gut. This term emphasizes the growing understanding of the gut-brain axis and underscores the holistic nature of health, where emotional, mental, and physiological aspects are interconnected.