• Event Brief
  • Humans & the Microbiome

Roundtable Brief: The Microbiome in Human Health, Ottawa

Jun 29 / 17
On April 5, 2017, Fellows of CIFAR’s program in Humans & the Microbiome held a roundtable discussion with funding partners and key individuals in the public health sector on the role of the microbiome in human health. The roundtable highlighted the program’s current understanding and gaps in knowledge about how microbes affect human health, development and cultural evolution, and their plans for how to they aim to shed new insights on these areas over the next few years. Discussions with participants explored where the program’s research intersect with core issues and areas of interest of their organizations, of which water, public health, antibiotics, nutrition and relevance to the brain were key themes of the conversation. This report summarizes the key discussion points from that roundtable.


All animals are colonized by large numbers of microorganisms on surfaces such as skin, mucosal membranes, teeth, and in GI tract. These microbes are collectively referred to as the microbiota. These microbes are numerous, outnumbering human cells by 10 times.

Microbes play an important role in our health, social behaviour and evolution. For example, gut microbes help us digest food, educate our immune system, influence the development and functioning of our nervous system. Disturbing the microbiota then by antibiotics and lifestyle changes can lead to poor health outcomes. In terms of behavior and evolution, good microbes can help humans adapt to new environments. 

A major benefit of the microbiota is to provide “colonization resistance” against incoming pathogens and there is mounting evidence that the microbiota plays an active role in this type of protection.

Over the past 50 years, we have seen a dramatic drop in the rates of infectious diseases including measles, mumps, hepatitis A, rheumatic fever and tuberculosis. At the same time, we have seen surges in immune disorders such as Crohn’s disease, multiple sclerosis, asthma and type 1 diabetes. This disappearing microbial diversity begs the question if we are living too cleanly and the need to better understand the role for microbes in human disease. 

To date, the microbiota has been associated with many conditions include type I diabetes, autism, allergies, obesity, cancer, and asthma to name a few. The complex interactions between the microbiota and humans is being actively explored and striking correlations are being found for particular disease states. There is however a need for research to move beyond correlative studies to ones that go to causality in order to understand the impact of the microbiome.

Researchers are discovering that many previous unsuspected areas of human health, such as childhood development, are being influenced by the microbes living within us. For example, the maternal microbiome has been shown to affect baby before and after birth with long-term consequences.

The Humans & the Microbiome program is probing the role of the microbiota in areas of human development, evolution and society (e.g. socio-cultural relations and change). The integration of health and anthropology makes this program particularly unique amongst other major international microbiome-based initiatives, giving it the potential to be truly transformative as a result. The broad range of funders is a reflection of the program’s reach and its importance to various stakeholders.

This multidisciplinary nature of the program is allowing the program to explore the role of the microbiome beyond just human health and disease. Non health-related questions being tackled include what is the history of the human microbiome and how does it change across generations, geographies and ethnicities? How has it co-evolved with humans to help us adjust to changing food supplies and new diseases? Has it actually guided human behaviour and cultural practices? Should we consider humans as ‘superorganisms’ or ‘holobionts’, inseparable from our microbes and our environment? And what does this mean to our understanding of what it is to be human?

The program currently has 19 Fellows & Advisors, spanning a variety of disciplines and geographic areas. Expertise in the program to date is provided in the areas of Microbiology, developmental and stem cell biology, metabolism and human physiology, evolutionary biology, history and social science, and anthropology.

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