Gut Feelings: The Microbiome and our health. 

This is a book written by Susie Flaherty and Our Health and is written by MIT press, 2022 

The recent epidemic notwithstanding, the next generations seem more prone to epidemics of chronic, non-infectious, inflammatory diseases.  There is a radical change required in the health care model as suggested by the authors to counter that by centering on the emerging body of research into the human microbiome. Rather than treat the microorganisms that populate the people’s guts as enemies, there must be better understanding of the complex ecosystem each human carries within, and work to create more holistic, preventative health interventions.  

Microorganisms have tremendous potential. This has caused medicine and science to take note.  When people view microorganisms through the lens of germ theory and infectious diseases, they treat it as a conflict between microbial ecosystems. The treatment is usually to prescribe antibiotics without discriminating between the microorganisms. Even if microorganisms contribute to diseases, they live in symbiosis with human hosts and can be instrumental in treating diseases ranging from cancer to neurological conditions. The authors content that microorganisms live in complex sophisticated civilizations that we did not appreciate yet. 

The Human Genome project made significant strides over three decades in addressing chronic inflammatory illnesses via better understanding genetics’ role in those diseases. Yet only 2% of the potential therapeutic targets have been addressed. They call the coexistence of humans and microorganisms a “coevolutionary destiny” 

Our lifestyle and the environment affect the microbiome’s composition which plays a significant role in the immune system function.  The microbiome extends beyond our body and connects us to a global ecosystem of microbes that live everywhere from soil to other creatures. The implications on our health and disease can be understood only when we consider the whole of the earth’s ecosystem as a continuous circle of life. 

Environmental factors that deplete the diversity of gut microbiota trigger poor health. It has been seen in some cases that when people change their dietary habits, overuse antibiotics, and overly sanitize human environments, they lose ancient microorganisms. This forms the hypothesis for “missing microbes” by Martin Blaser. For example, the East African hunter-gatherer tribe – whose diets and lifestyles resemble that of our predecessors, host several beneficial microorganisms that are found absent in other demographics. 

This forms the basis for the suggestion that the prevalence of chronic inflammatory disease in the West with a loss of microbial diversity which can then be addressed by fortifying the probiotics.  But there is no study that can differentiate the probiotics and map the human microbiome as the scientists did with the genome.  

The Human Microbiome project has had five primary aims since its inception which include: 

1. Isolate and identify microbial genome sequences, much like the Human Genome Project. 

2. Establish whether a “core microbiome” exists  

3. Find the relationship between alterations in the microbiome and disease. 

4. Develop new technologies and tools  

5. Reflect on the legal, ethical and social dimensions of microbiome sequencing. 

Good health outcomes entail balancing a complex ecosystem of microorganisms. This is evident in the conditions of homeostasis where there is a balance between states of health and disease.  This approach is paralleled and employed by holistic healing modalities – such as traditional Chinese medicine.  

The microbiome includes microorganisms such as bacteria, fungi, viruses, parasites, protozoa, archaea and yeast. So, bacteria is not the only kind that needs to be studied. Viruses or “virome” are also a key contributor to disease and its effects on health.  

The authors suggest a framework to consider much more complex and multidimensional explanations of the drivers of human health and disease with the notion of “five pillars” which are: genetic predisposition; exposure to certain environmental factors such as pollution; depleted mucosal barrier; immune system dysregulation; and a lack of balance in the microbiome. The easiest to manipulate are gut permeability, immune system function, and the microbiome.  

The gut microbiome influences the development or severity of many disease symptoms including the Gut inflammatory disorders, Obesity, Autoimmunity, Neurological and behavioral disorders, Cancer. A preventative approach to health care will employ predictive computational models.  

The authors argue that we have the power to stop these epidemics of non-infectious, chronic inflammatory diseases, if our scientific discoveries could be put in the microbiome domain at the service of the public health policies.  

The future holds promise with: 

Prebiotics trigger the activity of the colon bacteria. 

Probiotics ingest bacteria such as lactobacillus that people can use to balance the microbiome and boost immune function.  

Correlations are being mapped between strains of probiotics and the treatment of specific diseases. 

Synbiotics – the synergistic combination of prebiotics and postbiotics which can ensure desirable strains of bacteria colonize and survive in the gut. 

Postbiotics – include organic acids, peptides and enzymes. One way of consuming postbiotics is through fermenting foods.  

Psychobiotics – Microbiome research could result in the creation of a new class of probiotics to treat nervous system diseases such as mental health disorders and neurodegenerative diseases. 

Emerging health strategies include everything from prebiotics to psychobiotics. 

The authors summarize that these emerging fields of science benefit demand our investments in our time, talent, and resources to develop a roadmap for translating current and future scientific information into implementable clinical interventions that could change our collective destiny for the better.