Did you know that at least 90% of our bodies’ cells are not human? They are bacteria that live mostly in our digestive system (about 3 pounds worth!), as well as on our skin, in the lungs, and within the urinary and genital tracts.
These are “good” bacteria that help prevent disease by reducing growth of “bad” bacteria that can cause harm. These good bacteria also produce some nutrients that we need, help digest our food, provide energy in the form of short chain fatty acids, and stimulate our immune systems. And, just being there in sufficient numbers, they crowd out other bacteria that could cause us harm. The make-up of this bacterial flora varies from person to person, and may account for our variable risks for certain diseases.
Pharmacist, Dr. Kelly Dowhower Karpa, wrote Bacteria for Breakfast, Probiotics for Good Health after using probiotics (supplements of good bacteria) to cure her 2-year-old son’s infection of C. Difficile bacteria that was resistant to all antibiotics that his doctors tried. She did extensive research into how these good bacteria keep us healthy before beginning to write and, although some parts of her book are quite technical with explanations designed to answer questions doctors may have, the book is written for the general public. The goal of her book is to educate patients themselves, and to enable them to discuss their gut health with physicians. I will present a brief overview of some of the topics she discusses.
The book focuses on bacteria that live in our digestive systems, from the mouth where they prevent bad breath and dental cavities that can be caused by unfavourable bacteria, to the intestines where imbalances can promote inflammatory diseases. It explains how the stomach is designed to produce acid that kills bacteria that may be in our food but when acid is chronically suppressed with commonly used medications, such as Zantac, Losec (Prilosec), Nexium, etc., or is naturally reduced these bacteria are more likely to survive and the risk of gut infections is increased.
Food allergies can occur when overgrowth of bacteria damages the lining of the bowel, allowing undigested food particles to pass through into the blood stream, triggering allergic reactions to these large proteins that are not normally found in blood (termed “leaky gut syndrome”). This “leakiness” is also associated with inflammation, severe infection, organ failure and even death. Wide-spread activation of the immune system can lead to inflammation, severe allergies, asthma, eczema and even anaphylaxis (a life-threatening allergic response).
The incidence of these immune-related conditions has exploded in the past 50 years, suggesting non-genetic factors are involved. Two major changes are increased hygiene resulting in less exposure to various bacteria, and change in diet with more sterile pre-packaged food and less fresh, fermented and dried foods that would contain various bacteria. Our first exposure to bacteria usually occurs during birth, when passing through the birth canal, so babies born by Cesarian Section do not receive this initial dose of good bacteria and sometimes never develop an ideal gut flora. As well, if the mother has a less than ideal balance of bacteria, then this is what is passed on to the baby.
The effect of our bacterial flora can easily be seen in changes in the daily elimination function of the bowel. After treatment with a course of antibiotics, which kill healthy bacteria along with the infectious bacteria being treated, bowel function often changes with development of either diarrhea or constipation that can be corrected with supplements of good bacteria (probiotics). You may have noticed a difference in your digestion after eating fermented foods that still contain live bacteria. Chronic constipation that is resistant to various laxatives or returns as soon as the laxative is discontinued, will also sometimes respond to a course of probiotics. Keep in mind that probiotic supplements generally contain much more bacteria than you would get in foods like yoghurt, and might be preferred when trying to correct a serious imbalance in gut bacteria.
Dr. Karpa also explains an additional hypothesis for how bacteria may increase our risk for disease in detail with supporting evidence from studies. Although complex, I will try to explain this briefly…
The gastrointestinal tract is considered to be the largest immune system organ, and it communicates with the immune system throughout the body by producing immune particles called cytokines. Good bacteria activate the immune system, by stimulating production of cytokines that create a low-level inflammation. Some of these cytokines also enable production of the thick layer of mucous that protects the cells that line our digestive system. Still other cytokines are produced that limit the amount of inflammation that is created.
If we do not have the correct balance of cytokine-producing bacteria, we could be missing the protective mucous layer (allowing damage to occur in the intestinal wall with resulting leakage of undigested food proteins), we could be lacking enough stimulation of the immune system (leading to poor protection against common infections) or we could become less able to block excessive inflammation (leading to autoimmune diseases like allergies, asthma, inflammatory bowel disease, rheumatoid arthritis, etc.). The book cites many examples of improvement in chronic health conditions with adequate supplementation of probiotics (or good bacteria) and explains in detail how changes in gut flora are connected with various health conditions.
Disturbed gut flora has been described as potentially playing a critical role in the development of various autoimmune diseases (where the body’s immune system attacks an organ system) such as:
Inflammatory bowel disease
Type 1 diabetes
Rheumatoid arthritis
Hashimoto’s Disease (thyroiditis)
The book also briefly describes the benefit that some patients experience by also adding pancreatic enzymes or plant enzymes to help digest food, leading to a reduction in food allergies presumably by increasing the breakdown of proteins they contain. This might be another avenue to discuss with your physician if you have chronic severe food allergies.
As a pharmacist, I believe it is preferable to prevent disease or to treat the root cause, if possible, rather than to simply control the symptoms. I think this is why I found this subject fascinating and wanted to share a little of this information with you.
Other recent research I have stumbled across, suggests that gut bacteria may also be associated with changes in the frontal lobe of the brain that could be associated with autism or schizophrenia. Another report suggests a possible association between gut bacteria and the ability to create the protective myelin sheath (the covering that insulates nerve cells) that is destroyed in degenerative nerve diseases like Multiple Sclerosis. Probiotics have even been noted to increase the beneficial effect of vaccines. So you can easily see that many problems may originate with imbalances in the digestive system’s bacteria, and research continues to look for these associations and how they occur.
If you are interested in reading further, here is information on the book I have reviewed:
