The Gut, the Brain, and the Immune System

Our gastrointestinal system is responsible for 70% of the immunity in our body. Starting at the mouth it has contact with the exterior, being exposed daily to toxic substances and pathogens like virus and bacteria.

The gut immune system interacts directly with our gastrointestinal function in several ways; it can increase permeability, affect the contents by eliminating or allowing tolerance of antigens and even attack the mucous membrane as in Celiac and Chron’s disease.

It has been recently discovered that our gut has its own nervous system, similar to the central nervous system (CNS), with the capacity of processing information. As a result this intestinal nervous system communicates directly with the immune system. When a substance enters our digestive tract and the gut’s mini brain perceives it as unhealthy, it promptly activates the mucous membrane and motility to get rid of it, creating symptoms like abdominal pain and diarrhea. The immune system then becomes sensitized to the substance; a second exposure will trigger a coordinated increase in secretion of water into the intestine and spasm of the musculature. This action is mediated by the enteric nervous system (ENS), which has the ability of storing a series of programs to address different circumstances.

Healthandessence, Ursula Schmudt LAc

Stress has the same effect on our gut as the presence of an antigen. Due to the special connection between the gut and the brain, symptoms of a pathogen entering the area (abdominal pain and diarrhea) can be reproduced by mental stress.

Pathogens in our GI tract can also cross the blood brain barrier and cause inflammation in the brain. A common characteristic of neurodegenerative disorders like Parkinson’s, Alzheimer’s and MS is the presence of inflammation. Pathogens in our GI tract could cause neuro-inflammation in our brain. The similarity between the brain and the mini-brain of the gut could be the reason for a possible transfer of infection or inflammation between the two.

It is theorized that stomach pathogens, like Helicobacter Pilory, could affect the brain and induce Multiple Sclerosis, also Parkinson’s disease is more common in people that have suffered chronic constipation.

Our gastrointestinal system is closely connected to our respiratory system. It has been noted that people with inflammatory bowel disease have a higher incidence of broncho-pulmonary conditions; there is still no explanation for this. In Chinese medicine, the lung and the large intestine are related systems. This connection was established 4,000 years ago, now modern medicine is trying to explain this distal communication in which the lung replicates the inflammatory processes in the GI tract.

What this interconnection between gut, brain, lung, and immune system is showing us is the paramount importance of good digestion. What happens there reflects in other systems having the potential to create serious health problems.

Good quality food, water, efficient digestion and elimination, and stress management are integral for good health.

Ursula Schmidt, LAc


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