Research shows that there is such an extensive network of neurons lining the guts that scientists have nicknamed it our ‘second brain’. Our second brain, apart from handling digestion and nervousness, also helps determine our mental state and plays a role in certain diseases throughout the body. It doesn’t engage in any complex thought processes, but with its 100 million neurons it does enable us to control gut behavior independently of the brain and to ‘feel’ our inner world. Emotions are believed to be influenced by the nerves in the gut. 95 percent of the body’s serotonin is found in the bowels. Serotonin (The Confidence Molecule) is a chemical (a neurotransmitter) found in the body that carries signals along and between nerves in the brain, bowels and platelets. Among other things, serotonin is believed to contribute to our general state of well-being and happiness.
You can read more about this fascinating subject here: scientificamerican.com/article/gut-second-brain