Over growth of yeast in the gut disrupts the integrity of the lining of the intestine and can make patients. prone to develop food allergies. It disrupts gut neuropeptide production. The neuropeptide in the gut is. the same neuropeptide as in your brain. The disruption of the gut neuropeptide creates irritable bowel. symptoms which lead to irritable brain. Neuropeptides are âinformation moleculesâ, the basic units of a language used by cells throughout the.