A healthy gut, populated with beneficial bacteria, is a key to great health. At first blush it makes little sense what a bunch of microbes and the intestine have to do with autoimmune diseases, urinary infections, sinus infections, bronchitis, asthma, allergies, many types of skin rashes, and more. But it's true that the interaction of a healthy gut with our immune system is the cause, and the cure, for many common ailments.
Consider first that the largest part of the immune system surrounds the gut. The "gut associated lymphoid tissue" (GALT) provides about 80% of the infection-fighting white blood cells called lymphocytes. This lymphocyte arsenal includes immune system controllers called T cells, antibody producing B cells, and stealth defenders called natural killer cells.Second, there are over a trillion bacteria that live in our intestinal tract - more than all the cells in our body - and these bacteria have evolved with us over the eons. They are not just passengers on this journey through life, but rather they are active participants in our overall health. They depend on certain nutrients and behaviors that have been forged over thousands of years. If we do right by them, they will support and modulate our immune system, defend against infections, help break down our food, generate essential vitamins, metabolize hormones and bile acids, supply the intestine with energy, and stimulate the normal motility of the intestine.The normal functioning gut wall "teaches" the immune system how to behave, and the system is profoundly influenced by what is in the gut and what gets through the gut wall. A normal immune system relies on a normal gut. It starts at birth with the "inoculation" of bacteria during passage through the birth canal and is further supported through breastfeeding. During the first few years of life the ingestion of bacteria on food, dirt, and other "normal" things continues to instruct the immune system about tolerance. We can't simply attack everything that is foreign and have to learn a certain amount of tolerance.
The complex relationship between the beneficial bacteria and our immune system begins inside the gut. The lining of the intestine is covered with a "biofilm" of mucus and beneficial bacteria, much like a screen filter, providing a first line of defense against abnormal invaders. Below this filter lie block-shaped epithelial cells that are bound together by "tight junctions" providing very specific regulation of what is allowed to pass between the cells.The term "leaky gut" refers to damaged tight junctions allowing substances inside the gut to pass freely into the GALT. Leaky gut is well researched and we know that it can be caused by infections such as rotavirus or salmonella, medications such as ibuprofen, aspirin, steroids or antibiotics, as well as nicotine and alcohol. Certain beneficial bacteria protect and repair the tight junctions.With a total surface area of about 500 square yards, the intestine forms the largest interface between our system and the outside world. The gut lining is in constant contact with potential immune stimulators such as foodstuffs, toxins, microbes, parasites and allergens. Every single substance that passes through the gut wall is carefully "presented" to the immune system and undergoes a thorough identification process. Remember we have tolerance though and the immune system does not generate an attack on everything that comes through the gut wall.Here's where it starts to make more sense how a healthy gut can cure diseases in other parts of the body. The GALT is part of a larger network of immune systems that also include the NALT and BALT (nasal and bronchial associated lymphoid tissue) and primitive immune cells called "mast cells" which form the first line of defense being located throughout the skin, respiratory tract and the gut.The key here is that the immune cells from the GALT roam throughout the body and when they are activated they will disturb the other systems, leading to impaired defenses (e.g. bronchitis, sinusitis) or hypersensitive defenses (e.g. allergies, asthma, hives). Imbalances in the T-helper immune cells can lead to autoimmune diseases (overactive T-helper 1) or allergies (overactive T-helper 2).
The good news is that the different layers of function in the gut wall can be analyzed and repaired. A combination of simple tests can uncover problems in the gut interior, gut wall, and the immune system. Stool tests reveal the status of enzymes, good and bad bacteria, parasites, digestive residues, and inflammatory markers. A simple urine test can detect leaky gut. Blood tests can show immune system activation and diagnose immediate or delayed food allergies. Imbalances in the different branches of the immune system, namely T-helper 1 or 2, can be measured and treated to restore balance.Probiotics (pro + life) are live microorganisms which are administered into our system to confer a health benefit. We are learning that the hundreds of different species of beneficial bacteria do different things in the body. Some repair tight junctions and some prevent infections such as rotavirus, while others help digestion and aid in treating conditions such as irritable bowel syndrome. Specific strains are known to stimulate gut defenses and protective immune responses.When supplementing probiotics it is important to get a broad spectrum of bacteria and to get the product from a reputable company. My favorite is the routinely prescribed "Multi-Probiotic" from Douglas Labs. Other good brands include Jarrow, Enzymatic Therapy, PB8 and Therlac. Depending on the condition we routinely prescribe a dose of 5 to 50 billion organisms daily.Prebiotics are nondigestible nutrients that nourish and support the beneficial bacteria. Sometimes known as fermentable fiber, prebiotics include short or long chains of carbohydrates. The main types are inulin and fructooligosaccharides (FOS), and are found in foods such as Jerusalem artichoke, onion, garlic, bananas and asparagus. For healing leaky gut we use amino-acid based formulas containing L-Glutamine, such as "Intestamine" from Douglas Labs.With a holistic view of the intestinal-immune interaction, disturbances in the various communication systems can be identified and repaired. Welsh poet George Herbert said it well: "Take all that is given whether wealth, love or language, nothing comes by mistake and with good digestion all can be turned to health." Scott Rollins, M.D., is board certified with the American Board of Family Practice and the American Board of Anti-Aging and Regenerative Medicine. He specializes in bioidentical hormone replacement, thyroid and adrenal disorders, fibromyalgia and other complex medical conditions. He is founder and medical director of the Integrative Medicine Center of Western Colorado (www.imcwc.com) and Bellezza Laser Aesthetics (www.bellezzalaser.com). Call 970-245-6911 for appointments or more information.