Gut Health Influences and Their Relationship to Cancer Diagnosis The importance of a functioning and healthy digestive tract features widely in both mainstream and complementary health journals. Underneath the macro view focusing on function and form is a multilayered system responsible for and contributing to healthy gut function at an extraordinarily intricate level. Barrier integrity (intestines large and small), the internal (luminal) or mucosal protective lining of the barrier, gut microbe balance for optimal digestion, and efficient absorption of nutrients by the barrier or gut wall comprise this system. Healthy gut function is becoming acknowledged as a complex interplay between gut flora (microbiota), gut wall permeability and mucosal immunology (See Figure 1). More specifically, disruption of the normal balance of gut flora is associated with obesity, malnutrition, inflammatory bowel disorders, neurological disorders and cancer (Lozupone, Stombaugh, Gordon, Jansson, Knight, 2012). Increased gut wall permeability is implicated in local (gut wall) and systemic manifestation of autoimmune, inflammatory and atopic diseases (Ulluwishewa, Anderson, McNabb, Moughan, Wells & Roy, 2011). A combination of both unbalanced gut flora and increased intestinal permeability creates havoc within the body, impairing the functioning of many systems, creating widespread inflammation and pain. Despite this understanding, uniform practical guidelines to promote good gut health based on current research are slow to change.
Figure 1 Relation between intestinal permeability, intestinal microbiota, and mucosal immunology. (Bischoff, Barbara, Buurman, Ockhuizen, Schulzke, Serino, Tilg, Watson & Wells, 2014) Gut Flora (Intestinal Microbiota): A vital part of healthy gut function relates to the health of our gut flora, or trillions of microbes living in our intestines. Influencing normal physiology and disease susceptibilities, our microbiota is a complicated and influential ecological system. Most gut microbes are beneficial, playing a role in facilitating the extraction of nutrients form our food, protecting against harmful external bacteria and contributing to normal immune function (Luzupone et al, 2012). When certain strains of bacteria become out of balance in the whole gut ecology, the implications for this can be experienced throughout the body. Importantly it is their balance and resilience that is more closely linked to health or disease. There are many factors influencing the status of healthy gut microbiome.
It is widely understood that how we are born influences the quality of microbiome (whole body beneficial bacteria) seeding we receive from our mother. Vaginal delivery ensures newborns receive bacteria from their mother and contributes to the ongoing development of the individual s microbiome. Our microbiome, including gut flora develops out of this genetic pool dramatically changing over the first three years of life, increasing diversity and stability of bacteria, important for future gut health in the adult. Along with delivery status, environmental exposure, hygiene, diet (familial and cultural), antibiotic use, breastfeeding status and birth order can all influence the potential resilience and diversity of the microbiota (Lozupoine et al, 2012; Bersen, de Jongste & van der Wouden, 2003). Resilience is an important factor in maintaining balanced gut flora. This relates to the differences observed in individual responses to changes in the gut flora by medicinal, environmental and dietary changes, and the subsequent proliferation or absence of disease states within the body. Diversity of and presence of co- operative bacterial strains enhances gut ecology resilience and is typically seen more in cultures with very high fiber diets (Lozupone et al, 2012). The influence of resilience and diversity are a hallmark of what is anecdotally know as a cast iron stomach, or the ability to withstand potential threats without a fundamental change to the gut ecology and therefore, function. More recently there has been mounting evidence that has identified the communication between gut flora and intestinal epithelium, and the influence of floral balance on the intestinal barrier integrity and function. Gut Wall Permeability: The function of the gut wall is bi- layered. Externally, providing a physical barrier and internally, a functional immunological barrier comprised of Tight Junctions (TJ), connectors between the epithelial cells on the internal surface of the intestines, and the mucosal immunological system. When balanced, they protect the body from antigens and pathogens, and from partially digested food molecules from entering the blood stream, creating serious inflammation and consequences for overall health.
Tight junctions (TJ) are are constantly being remodeled for a number of reasons. Apoptosis, or programmed cell death, necessary to replace intestinal epithelial cells over their life span, and poor molecular modeling due to lack of appropriate signaling (Bischoff et al, 2014). Both events create vulnerabilities in the barrier permeability if, for whatever reason, the process is unbalanced. vulnerability in gut barrier permeability can be short lived and repaired by healthy resilient gut bacteria, or longstanding, in which case it is usually accompanied by overgrowth of particular gut bacteria, reducing function and creating inflammation and disease. Processes or treatments that shorten the life span of epithelial cells exacerbate this vulnerability in gut barrier function. Examples of such treatments include chemotherapy and radiation. Both create an increased rate of apoptosis on these rapidly dividing epithelial cells as part of their systemic effects of treatment (Wardell & Bowen, 2013). Signaling pathways used by dietary components and several gut bacteria strains regulate TJ structure and assembly (Ulluwishewa, et al 2011). Absences of dietary components and/or imbalances in these specific bacteria affect the efficiency of repair to the gut wall. This effect can be cyclical. However, if ignored it can potentially create long term health issues related to leaky gut syndrome and dysbiosis. Deeper within the gut wall lie blood vessels, smooth muscle cells and components of the enteric nervous system. These components use signaling pathways to contribute to barrier regulation by monitoring mucosal health and activating specific defense mechanisms during times of threat to membrane integrity (Birschoff et al, 2014). Specific cells located in the gut wall produce serotonin and histamine. Regulation and re- uptake of serotonin contributes to levels of histamine and inflammatory response in the body. Particular bacterial species can colonize the mucous layer on the internal surface of the gut (lumen). When out of balance, this process creates a thickness in the mucoid layer, impairing absorption of nutrition and causing deregulation of TJs (Bischoff et al, 2014). Relevance to People With Cancer: The link between a diagnosis of cancer and imbalance in gut flora and permeability is not certain, however, leaky gut and dysbiosis certainly predispose individuals to chronic
inflammatory states, immune dysfunction- both of which are implicate in abnormal cell growth and proliferation. Cause and effect of gut dysfunction in this case is not certain however, from a logical viewpoint, the dysfunction of the immune system present in cancer development implies some level of long term impairment of effortless, healthy gut function. It is accepted that most people suffer some disruption to gut function during conventional cancer treatments. It is thought that the targeting by chemotherapy of rapidly dividing cells in the body can have a great impact on the integrity of TJs and gut microbe balance. This theory is bourne out by recent research, highlighting a possible connection between the effects of chemotherapy on the molecular structure of TJs and relationship to chemotherapy- induced gut toxicity (Wardell & Bowen, 2013). It is clear that people having chemotherapy treatments experience nutritional malabsorption, exposure to gut borne pathogens and imbalanced gut bacteria, creating inflammation, pain, nausea, diarrhea, anorexia, general frailty and infirmity. These effects on the individual and their gut health can be transitory or longstanding relational to pretreatment resilience and diversity of gut bacteria, and whether they seek active treatment to rectify the damage. What can help? Healthy gut function, particularly where damage, dysfunction and disease persist, is the realm of appropriately trained health practitioners. As discussed in preceding paragraphs, factors influencing healthy gut function are part of a vastly complex and finely tuned network of feedback loops, regulation and balance. We all have different genetic and cultural components driving the ecosystem of our digestive tract and as Westerners, we tend towards a less diverse combination of gut bacteria, reduced resilience and increase susceptibility for gut dysfunction. Response to any dietary and lifestyle changes can be slow, with long- term commitment and self- awareness being essential for success. People who have diagnosed or suspected gut dysfunction, particularly those who have undergone conventional medical treatment for cancer, referral to an experienced professional constitutes ethical professional practice. Naturopaths and Integrative Doctors with Biobalance training tend to have more comprehensive and up to date training of relevant nutrition, biochemistry and testing to support individualized needs for repair and restoration of gut health, both during and after cancer treatment.
Commonly, people are told to eat what they want while using conventional cancer treatments. They are encouraged to eat junk food of little to no nutritional value to help with predicted weight loss. It is thought that discussing dietary changes will create more stress for individuals and in some conventional medicine circles there is doubt regarding any positive impact of diet on the effect of treatment, minimizing of treatment side effects or prognosis of cancer. It is not uncommon to see bowls of chocolates or doughnuts in chemotherapy suites for consumption by patients and their carers. This is counterintuitive to healing and what is widely understood about supportive gut care. Hallmarks of supportive gut care include the consumption of whole, easily digestible, nutritious foods in small amounts, more frequently during the day. Limiting or avoiding grains, dairy and sugar, is reasonable given their effects on digestion, gut health and permeability and their almost direct conversion into sugars- a known stimulant to cancer growth. Qualified health practitioners often encourage the use of food diaries and meal plans to help identify reactions and facilitate behaviour changes and food choices. Complementary therapists will often recommend the consumption of organic produce where possible. While there is limited evidence that the nutrition is greater in organic produce, it is act of reduced ingestion of toxins and chemicals that is more important. Research has identified a role for pre and probiotics in building diversity in the gut microbiota, facilitating a cascade effect for gut permeability and nutrition absorption (Lozupone et al, 2012). Vitamins A & D play a vital role in regulation of gut permeability along with their other roles of regulating cell differentiation and proliferation (Birkoff et al, 2014). As Oncology massage therapists we can encourage oncology clients to seek professional advice regarding their gut health as part of their board of directors team approach to cancer treatment. Benefits could include minimization of gut related side effects common with conventional therapies, an improved ability to maintain resilient and diverse gut bacteria for flourishing health and an investment in their recovery following diagnosis and treatment.
While optimal gut functioning is complex, once good gut health is achieved, maintaining it can be deceptively simple. During occasional times of mild food obsession, I find the wise words of Michael Pollen in his book How to Eat, inordinately comforting. Eat food. Not too much. Mostly plants Bibliography: 1. Lozupone CA, Stombaugh JI, Gordon JI, Jansson JK, Knight R, 2012, Diversity, stability and resilience of the human gut microbiota, Nature, 489(7425):220-230. 2. Ulluwishewa D, Anderson RC, McNabb WC, Moughan PJ, Wells JM Roy NC, 2011, Regulation of Tight Junction Permeability by Intestinal Bacteria and Dietary Components, Journal of Nutrition, Critical Review, Pp 769-776. 3. Bischoff SC, Barbara G, Buurman W, Ockhuizen T, Schulzke J, Serino M, Tilg H, Watson A, Wells JM, 2014, Intestinal permeability- a new target for disease prevention and therapy, BMC Gastroenterology, 14:189. 4. Bersen RM, de Jongste JC, van der Wouden JC, 2003, Birth order and sibship size as independent risk factors for asthma, allergy, and eczema, Pediatr Allergy Immunol 14(6): 464-469. 5. Wardell HR, Bowen JM, 2013, Chemotherapy- induced mucosal barrier dysfunction: an updated review on the role of intestinal tight junctions, Current Opinion in Supportive and Palliative Care, 7(2): 155-161.