In a healthy intestinal tract, bacteria are plentiful. There are more bacteria in our intestinal tract than there are cells of “our” entire body. In fact, there are about ten times more of “them” than there are cells we consider to be “us.” We normally harbor about four hundred types of organisms in our intestines. Some are oxygen-loving, but most are anaerobic, meaning they thrive only when oxygen is not present. This has made them challenging to study, since they die when we expose them to air. Still, they are among the most essential and prevalent of our gastrointestinal flora friends. From a human perspective, there are lots of beneficial roles for these industrious bacteria. Some of them include:
Immune support: About seventy percent of our immune system is located in the digestive tract. “Probiotic” bacteria enhance many of the functions of the immune system, acting independently as an adjunct to our cells’ immune system.
Digestion and absorption of foods: The digestion of certain foods, especially carbohydrates, is facilitated by the friendly organisms of the small intestine. The foods we eat nourish their colonies. All we take in, whether food or thought, is important for determining the health of internal bacterial colonies. Each type of bacteria has its favorite diet. The kinds of bacteria most associated with vibrant health thrive upon naturally fermented foods like sauerkraut, miso, yogurt, and kefir, as well as certain fats and animal foods including saturated fats. They also require some types of fiber found in vegetables, fruits, and whole grains. They do best when we are calm, happy, and relaxed.
Barrier to pathogenic bacteria: Healthy bacteria crowd out the unwelcome visitors. When beneficial microbes that evolved along with our GI tracts colonize this region, there is not much space available for imbalanced flora to take hold. Bacteria also secrete chemical mediators that support their own species and others with whom they are harmonious. These same chemical mediators suppress bacteria that are incompatible.
Prevention of allergies: Beneficial bacteria teach the immune system to distinguish between the antigens of harmless and helpful flora and foods, and potentially dangerous ones. Allergies are a type of oversensitivity. During an allergy, the body overreacts, sensing harm in things that are not innately harmful. The presence of flourishing colonies of beneficial bacteria decreases the incidence of allergies.
Manufacture of vitamins: There is evidence that healthy forms of E. coli manufacture vitamin K in the human intestinal tract. In some animals, vitamin B12 is manufactured by intestinal flora. Humans, however, must consume this vitamin from animal food sources.
Elimination of toxins: Probiotic bacteria eat many of our waste products, breaking them down to component nutrients. These are recycled. What is not used is eliminated within the feces.
Stimulation of tissues: Probiotic bacteria are essential for normal development of the intestinal tract. Certain tissues like the lymphoid Peyer’s patches of the intestinal tract, and the entire large intestine, require the presence of healthy bacteria for growth and maturation.
Prevention of disease: Imbalanced and reduced numbers of healthy flora are found in people with inflammatory bowel diseases like Crohn’s disease and ulcerative colitis. There are also imbalances observed in most people with irritable bowel syndrome, asthma, eczema, and autoimmune illnesses.
Two thousand years ago Hippocrates observed that the health of the entire body begins in the gut. Today we understand that our health is intertwined with that of the intestinal microbes. The extent to which healthy bacteria sustain our gastrointestinal health can be dramatized by just one example. It actually takes ingestion of more than ten million salmonella bacteria to sicken a healthy person or animal with good levels of supportive intestinal bacteria. But if one were artificially raised in a sterile environment, without any gastrointestinal flora, a mere ten bacteria would be sufficient to cause disease. As our own bacteria care for us, they are providing a good home, in us, for their offspring. Our thriving means that they are fruitful and multiply.
This “Transforming Health” inspiration is from Marcey Shapiro, MD, Integrative Medicine Physician
Excerpted from Transforming the Nature of Health: A Holistic Vision of Healing That Honors Our Connection to the Earth, Others, and Ourselves by Marcey Shapiro, MD, North Atlantic Books, copyright © 2012 Marcey Shapiro. Reprinted by permission of publisher.
Stay tuned for more thoughts from Marcey Shapiro, MD, on “Transforming Health” and Heart Centered Living.