The gastrointestinal (GI) tract is a crucial part of our physiology. It is of course the route of absorption of the nutrients we need for life, but it also happens to be the site of most of our immune system and a major source of neurotransmitters – the chemicals that determine our emotional state.

It is the intestinal immune system that is getting a great deal of attention among biomedical researchers. The GI immune system has to be very “smart” since it is one of the body’s most important gatekeepers. The gastrointestinal tract has to decide not only what food is and what is not, but also what is friend and what is foe among the billions of organisms that reside there.

How does the GI immune system get so smart?

It appears that our exposure early in life to intestinal bacteria is what tones and educates our immune system, and the disruption of this flora with antibiotics or poor diets can cause the immune system to misbehave in various ways (allergy, autoimmune diseases, etc.). This poorly regulated immune system can cause inflammation that may create problems in many parts of the body as diverse as the brain and the heart.

Our digestive and assimilation of food and nutrients is also a complex, multi-staged process. After chewing and mixing with salivary enzymes, the next place of digestion requires adequate secretion of hydrochloric acid by the stomach which is important to activate digestive enzymes down stream. This acid phase is often under-functioning and can be further compromised by acid blockers which have become very popular for treating reflux and heartburn.

Further down stream are a host of enzymes that break down the protein, fat and carbohydrates in our diet to a form that can be absorbed. Incomplete enzyme function can lead to malnutrition and possibly food allergy.

* The lining of the intestinal tract has to be smart and selective as well. If it is damaged (by medication, infections or other sources of inflammation), it can allow incompletely digested food items into our bodies with a variety of negative results. This increased intestinal permeability has been referred to as Leaky Gut Syndrome.

So, given the complexity and multiple functions of our gastrointestinal system, what should we do to maintain it in good working order?

Firstly, we should look at our diet. It should be nutrient dense (lots of vegetables and fruits) and should avoid highly processed and refined foods, especially sugars that cause disruptions of normal intestinal flora. Alcohol and drugs like Motrin can also damage the intestinal lining (leaky gut). The diet should also be high in soluble fiber (which feeds ‘healthy’ bacteria) and insoluble fiber (which promotes elimination).

The diet should avoid any foods to which the individual is allergic or hypersensitive (there are a number of ways to test for food allergy, including an Elimination Diet.)

If there is evidence of poor digestive function, supplemental enzymes may be taken with meals and there are even ways to promote increased stomach acid if necessary.

Finally, there is the question of intestinal flora. One often finds overgrowth of unhealthy bacteria, fungi and parasites, and these can be treated with natural agents or pharmaceuticals. Inadequate levels of the healthy ‘probiotic’ organisms can be addressed with supplements and in stubborn cases there are special diets (Specific Carbohydrate, Body Ecology) that can be employed to normalize intestinal flora. The leaky gut can be treated with nutrients that heal the intestinal lining.

It’s obvious that gastrointestinal balance is complex and may require a comprehensive effort at restoration but the benefits can have widespread effects on health and wellbeing.