Microbiome / Gut Health
By Maris Paden
Background
The term microbiome refers collectively to the trillions of bacterial organisms that primarily live in the gut (Ursell et al. 2012). These symbiotic organisms include archaea, protists and fungi, making up more than 90% of the cells in the entire body (Warinner & Lewis 2015). While the terms microbiome and microbiota are colloquially interchangeable, microbiome technically refers to the “community” of cells and their genes, while microbiota refers to the cells themselves (Ursell et al. 2012). Altogether, the microbiome weighs as much as the average human brain. As can be seen by the world cloud in Figure 1 below dietitians associate the term with bacteria, the gut, diet, and health. However, the microbiome has many functions beyond digestion. The microbiome contains an extraordinary diversity of genes and is linked to “immunologic, hormonal, and metabolic homeostasis” (Salvucci 2014, 8). It also plays critical roles in vitamin production, allergies, heart disease, chemotherapy effectiveness and more. Recent scientific evidence also suggests there are links between the microbiome and anxiety, depression, autism, and schizophrenia (Amato 2016). The more scientists learn about the microbiome, the more power they are giving it in determining health and disease (Guinane and Cotter 2013).
Research on the microbiome is booming. As an offshoot of the 1990 Human Genome Project, the National Institute of Health (NIH) began the Human Microbiome Project (National Institutes of Health 2017). This project is a developing research study that aims to better understand the microbial communities that live inside the human body and the roles they play in health and disease. It is currently focusing on the areas of pregnancy and preterm birth, the onset of Inflammatory Bowel Disease, and the onset of Type 2 diabetes in relation to the microbiome (National Institutes of Health 2017). In addition to getting regular sleep and exercise, fermented foods such as pickles and kombucha, as well as Greek yogurt are beneficial to maintaining gut (Callaway 2015).
Figure 1. Essential Probiotics ““Human Microbiome vs. Microbiota: What’s the Difference?” Word Cloud by SCD Probiotic Dieticians (2016).
Perspectives and Controversy
The microbiome has been particularly controversial in its relation to Clostridium difficile and other gastroenterological disorders (Wolf-Meyer 2017). There has been tremendous success with the use of fecal microbial transplants (FMTs) in treating Clostridium difficile, irritable bowel syndyome, constipation, and neurological conditions such as Parkinson’s (Rohlke and Stollman 2012). This procedure takes a healthy microbiome from the stool of a donor and transplants it into the sick patient. In a 2015 TEDx talk, Dr. Mark Davis, a naturopath, discusses how this works and the benefits that can ensue from the process. The talk can be viewed here: “Fecal Transplants & Why You Should Give a Crap,” to gain the perspective of a FMT advocate. However, this process is experimental and is not covered by United States medical insurance plans. While some patients are willing to pay as much as $10,000 for the procedure, others are attempting FMTs at home after acquiring stool donations from friends and family (Wolf-Meyer 2017). Because of the Food and Drug Administration’s restriction of FMTs to approved clinics, patients are conducting these risky procedures without medical-practitioner oversight, endangering both the already sick patients as well as the scientific validity of the procedure (Wolf-Meyer 2017). These at-home procedures threaten the government’s control over the medical practice and subsequent control over the human body. For a person unable to gain access to affordable healthcare, at-home procedures are a critical and positive step to restoring gastro-intestinal health. Advocates for FMTs are likely to continue to lobby for more affordable access to this procedure, be it in a clinical setting or a controlled home environment.
A second relevant controversy surrounding the microbiome is the high rate of caesarean section births in the United States and subsequent infant immunity (Salvucci 2014). As aforementioned, the explosion of research on the microbiome has revealed its inextricable link to the immune system. Much of a newborn’s microbiome composes as it passes through the vaginal canal, a hub for microbial bacteria (Salvucci 2014). Babies born via caesarean section do not pass through the vaginal canal and are not exposed to entire populations of bacteria. Recent studies are suggesting that babies born through C-section have lower diversity of microbiota (Salvucci 2014). Hospitals that are aware of this take vaginal swabs from the mother and touch the bacteria to the baby’s mouth and face. However, critics propose that babies are first exposed to their mother’s microbiome in utero, not during birth, and that the weaker microbiome stems hereditarily from the mother (Salvucci 2014). Further research is needed to validate either of these claims.
Historical Context
Historical documents show studies on the microbiome began as early as the 17th century. In 1680, the Dutch scientist Antonie van Leewenhoek compared his oral and fecal microbiota to assess bacterial variety (Ursell et al. 2012). In the past three centuries, most of the research on the microbiome has been conducted on affluent, metropolitan individuals from Western society, leading our understanding of the diversity in the microbiome to be limited. Recent technology is now enabling scientists and anthropologist to begin to analyze the evolution of the microbiome through the feces and dental plaque of human ancestors (Warinner & Lewis 2015). Gastrointestinal experts have found support to demonstrate that industrialization, sanitation, and globalization have changed the human relationship with microbiota (Warinner & Lewis 2015). Scientific evidence suggests that “diseases of civilization” such as allergies are exacerbated by changes in living condition, diet, and antibiotics (Warinner & Lewis 2015). The ancestral microbiome is characterized by a greater diversity of microbiota than present today. Anthropologists and bio-archeologists are finding evidence to suggest that when humans transitioned from a hunter-gatherer society to an industrialized diet, they lost a population of microbiota high in anti-inflammatory properties (Warinner & Lewis 2015). This may have contributed to the rise of chronic inflammatory diseases in modern people. Additionally, the rise of antibiotics has wiped out some colonies of microbiota entirely (Wolf-Meyer 2017). Understanding the evolution of the microbiome can provide greater insight to human adaptation to climate change, human migration, and expand our definition of what it means to be human. By analyzing changes in the early microbiome, society will gain a deeper understanding of the environmental factors that led early humans to disperse, and the social forces that emerged from such migration. Microbiome experts hope to teach the public that the human body functions in a partnership with the trillions of bacteria living inside it, and these bacteria must be cared for to maintain digestive health, immunity, and more (Salvucci 2014).
Connection to Politics of Health
This term is connected to politics of health because of its links to biopower (Foucault 1978). Biopower is a term coined by Michel Foucault and refers to the subjugation of bodies and control of a population. The government and other bodies of power utilize biopower to control populations through concepts such as racialization, gendering, and normalization (Wolf-Meyer 2017). However, the microbiome rejects these classifications, defying any attempt of control. Medications that may work to control one person’s gastrointestinal diseases may not work on another. The trillions of bacteria living in the gut and other places within the body are highly diverse and constantly evolving, leading scientists and doctors alike to struggle to control the microbiome (Wolf-Meyer 2017). Despite their inability to manage the collective of organisms, scientists are giving the microbiome more and more determinative power in health (Wolf-Meyer 2017). Each person’s combination of microbiota is as unique and complex as that person’s DNA. The sequencing of conventionally accepted “healthy” microbiomes reveals that there are limitless combinations of what “healthy” and therefore “normal” can be. Without a standard for “normal” and “regular,” it is more difficult for the powerful to classify someone as abnormal and irregular. Furthermore, as more people begin to address their microbiome at home, be it through changes in diet and behavior or experimental fecal microbial transplants, the government loses its grasp of control on medicine, making the microbiome an agent to stand against biopower (Wolf-Meyer 2017).
This rejection of scientific control also ties closely to the concept of demedicalization. Demedicalization is the process by which something ceases to be viewed as an illness or disorder (Halfmann 2011). Though the medical establishment attempts to medicalize the microbiota, the inability to regulate and control the microbiota makes this extremely difficult. At-home procedures like FMTs and simple diet tips are demedicalizing the microbiome as individuals are able to cater their own care. Additionally, the great diversity of the microbiome between individuals proves it is not a “one-size fits all” entity to treat. Individuality gives people agency with their own microbiome, enabling them to self-analyze what helps and what doesn’t without the care of a doctor (Salvucci 2014).
Bibliography
Amato, Katherine R. “An Introduction to Microbiome Analysis for Human Biology Applications.” American Journal of Human Biology, 2016. doi:10.1002/ajhb.22931.
Callaway, Ewen. “Microbiomes Raise Privacy Concerns.” Nature News. May 11, 2015. Accessed September 25, 2017. http://www.nature.com/news/microbiomes-raise-privacy-concerns-1.17527.
Foucault, Michel. 1978. The history of sexuality. New York: Pantheon Books.
Guinane, Caitriona M., and Paul D. Cotter. “Role of the Gut Microbiota in Health and Chronic Gastrointestinal Disease: Understanding a Hidden Metabolic Organ.” Therapeutic Advances in Gastroenterology 6.4 (2013): 295–308. doi:10.1177/1756283X13482996.
Halfmann, Drew. “Regonizing medicalization and demedicalization: Discourses, practices, and identities.” Sage Journals, 2011. doi: 10.1177/1363459311403947.
“Human Microbiome Project – Microbiome Project Program Highlights.” National Institutes of Health. May 4, 2017. Accessed September 18, 2017. https://commonfund.nih.gov/hmp/programhighlights.
“Human Microbiome vs. Microbiota: What’s the Difference?” Essential Probiotics, 10 Feb. 2016, www.essentialprobiotics.com/human-microbiome-vs-microbiota-whats-difference/.
Rohlke, F., & Stollman, N. (2012). Fecal microbiota transplantation in relapsing Clostridium difficile infection. Therapeutic Advances in Gastroenterology, 5(6), 403–420. http://doi.org/10.1177/1756283X12453637
Salvucci, Emiliano. “Microbiome, Holobiont and the Net of Life.” Critical Reviews in Microbiology, 2014, 1-10. doi:10.3109/1040841x.2014.962478.
Ursell, Luke K., Jessica L. Metcalf, Laura Wegener Parfrey, and Rob Knight. “Defining the Human Microbiome.” Nutrition Reviews 70 (February 2012). doi:10.1111/j.1753-4887.2012.00493.x.
Warinner, Christina, and Cecil M. Lewis. “Microbiome and Health in Past and Present Human Populations.” American Anthropologist 117, no. 4 (2015): 740-41. doi:10.1111/aman.12367.
Wolf-Meyer, Matthew J. “Normal, Regular, and Standard: Scaling the Body through Fecal Microbial Transplants.” Medical Anthropology Quarterly 31, no. 3 (2017): 297-314. doi:10.1111/maq.12328.
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