THE MICROBIOME SUMMIT : The Paradigm Shift
Microbes I: Biodiversity Losses & Human Health
Dr. Susan Prescott, MD, PhD & Dr. Alan Logan, ND
Together, Dr. Susan Prescott and Dr. Alan Logan wrote the book The Secret Life of Your Microbiome, Why Nature and Biodiversity are Essential to Health and Happiness, published in 2017. This video is the first of three that they appear in together, where they discuss how dysbiosis – which describes a loss of microbial diversity – is also happening on a larger scale, and what this means to human health. Everything is connected.
- Alan:
- Welcome to the University of Toronto’s Microbiome Summit Series. I’m here with Dr. Susan SUSAN; Pediatrician, Immunologist. My name is Alan Logan, and it’s wonderful to be here with Susan, who is back to Toronto for the first time in 17 years.
- Alan:
- You did do some of your training here in the fine City of Toronto as we would call it.
- Susan:
- Yes.
- Alan:
- We’re here to talk about Marvels of the Microbiome and fixing the Dysbiosis Sphere. So, we’ll talk a bit about what the Dysbiosis is as we move forward.
- Susan:
- Yes. But first, it’s wonderful to reflect on how this conversation began when we met in Japan in 2003 when we were invited to a summit on Beneficial Microbes. So, there we were to talk about Probiotics and Health. We talked about a whole lot more. And we talked about the importance of Biodiversity, nature and human health. And I found that all very – very exciting. And I was there because I just published a paper in the Lancet one of the top Journals. It was really one of the important pieces of research showing the importance of the Microbiome for immune development. That work really formed the foundation for showing that our immune responses to the environment actually begin even before we’re born and microbiological exposure that occurs in the early period after birth and even before is very important for immune maturation.
- Alan:
- Yeah. Which has far-reaching effects throughout the lifespan. I mean it was a profound finding.
- Susan:
- Yes. One of the most obvious implications was the relevance to allergy because we know that if you don’t get microbial exposure in the appropriate amount and variety and in that early period, then you’re much more prone to allergies. So, that’s why I was there, and of course, you were there because of your interest in the gut brain axis, which I found fascinating. You were the first person to propose that beneficial microbes or probiotics and their products might be a benefit in mental health disorders.
- Alan:
- Yeah. And the might being the large asterisk that exists with that conversation. It still does today, but at that time in 2002 actually the year before we met; I was that a probiotics conference in Montréal and was literally laughed at for even making such a bold suggestion. So, the times have changed. And it’s wonderful for you and I with our long-standing companionship to be able reflect on these things here in 2017.
- Susan:
- And it’s wonderful that we’re being able to now use this as advocates really, for the environment. For linking the health of our inner environment with the health of our outer environment and the importance of nature and biodiversity on this planet.
- Alan:
- Yeah. It’s very true, and one of the things that you have always positioned your own research in the microbiome many years is the fact that it’s all connected. And that really is one of the primary themes throughout the rest of our panel discussion here tonight.
- Susan:
- Absolutely. And we want to start by talking about what we’re going to call about the holissphere and taking a holistic view of life and biodiversity.: Because often when people would start talking about the microbiome and dive right into the microscopic level, and we’re going to do the opposite. We’re going to take a zoom out position and think about how our remarkable world in the context of the universe has provided such an incredible perfect environment for life. And that life began on this planet. A simple uni-cellular organisms, much like the microbes that we find today in the stromatolites formations in Western Australia. And it’s not far from where I’m from in fact. These are these rocky out crops, which are actually made by microbes. But they are very similar.
- Alan:
- Yeah. It’s true and they’re literally laying down these rock formations. And they have been doing so for 3 ½ billion years. I mean it’s absolutely amazing.
- Susan:
- It is. And if you think about it today, microbes still contribute to a substantial portion of them the biomass on our planet today. There are over a trillion-different species of microbes. And we as humans and all different spaces on this planet have actually co-evolved in symbiotic relationships with microbes. Because microbes are essential to the bio-diversity that sustains all life on this planet. And they’re part of all life on this planet. And this relationship between hosts and microbes really underpin the evolutionary success of what we describe as the biosphere.
- Alan:
- It’s true. The biosphere, again, being this five-mile envelope from the ocean floor to the level of the atmosphere where we’ve proven that microbes can reside, and it’s actually under threat as you know, we will talk here in our session about the forces that are working against the biosphere. Hence, our descriptive dis-biosphere. And what we might want to do about that.
- Susan:
- Yes. And we need to understand that it’s the symbiotic relationships, which have evolved over the millennia are really key to adaptability and our resilience. Which are under threat when we look at how the biodiversity is decaying. Because human health depends on the health of the biosphere and we know that the health of the environment and biosphere, really, is measured by its biodiversity. So, anything that threatens biodiversity is really a threat to human health.
- Alan:
- It’s a threat to human health. It’s a threat to life on earth really, and as we will later segue specifically into microbes, it’s worth pointing out that those same lessons are true inside let’s say the gut where the diverse population of microbes generally equates to health. And that’s the same thing in the external environment. Greater diversity leads to a healthier environment outside.
- Susan:
- And healthier bodies because we have to remember that we are in essence small microbial than we are human, but our bodies harbour probably over 100 trillion bacteria, and that these bacteria therefore, comprise of significant proportion of the cells in our body and a sizable part of our genetic material.
- Alan:
- And the key point about that genetic material is that its functioning. It has specific functions that confer benefit to us as human beings. So, these are in many ways, our friends. They’re going to work for us. They’ve got a lunch pail and a hard hat on if you will. In terms of what they may do for us.
- Susan:
- And they’re responsive to rapid changes in the environment. They change in response to the environment. And they’re also, therefore, an important therapeutic target as we move forward to try and address health issues.But all around us today of course, we say that biodiversity in a global level is at risk. And we’re seeing an increasing loss of species, environmental degradation, and essentially, what we call dysbiosis is really a lot more than just microbes. Isn’t it?
- Alan:
- Well, you and I have talked for a long time, and you’ve put it front and center in some of your key papers. Dysbiosis, although, viewers or listeners of this session may understand that to be a shift in microbes. For example, encroachment of pathogenic microbes. A loss of your beneficial microbes. It’s sort of found its way in as a micro biological term. But what it actually means and the definition, which certainly predates its use by microbiologists. It means; life in distress. And your point has been that there’s a global dysbiosis ongoing right now. Life is in distress when we talk about bio-diversity losses.
- Susan:
- So, we’re seeing threats to the macro bio-diversity but essentially, that’s reflected or mirrored by what’s going on at the micro level, and we’ve intended not to say that is obviously. So, we’re seeing a huge impact of human activity on the planet today, and we’re seeing altered balance, and we’re seeing climatic change. We’re seeing effect on our food supply. Our air quality. Our water quality. We’re seeing pollution. Contamination. All promoting this very unhealthy relationships between humans and the environment, and a lot of this of course begins very early in life. And it’s the same description, that you’ve made in your work as well, of dysbiotic drift. This shifting of the health of our environment. This actually has a dual burden.
- Alan:
- Right. Well, your work earlier on in the Lancet, which we made reference to, that ground-breaking research, illuminated the hygiene hypothesis. Which, many would know to be a lack of diverse microbial experiences early in life right? Can lead to improper education of the immune system. It can set yourself up for perhaps for allergic diseases and so forth. So, the hygiene hypothesis is the absence of exposure to diverse microbes. But there’s the other side of that, which is Westernization. Urbanization. Right? Increased consumption of fast foods. Increased exposure to environmental pollutants and tobacco smoke or what have you. All of those things can influence dysbiosis in the microbial terminology and that’s compounding the hygiene aspect of this conversation.So, you’ve called this a “Dual burden?” That we are now experiencing in westernized nations.
- Susan:
- So essentially, that means that we’re losing the protective factors, and we have an excessive toxic factors. And I think it’s fair to say, and we should make no apology for saying that the commercial forces at play in our world today and the absence of policy around some of these things actually drives dysbiosis by default.
- Alan:
- By default, and we will talk more about that in detail in a few minutes as well.
- Susan:
- But we talk about green space a lot. But what about the opposite? Which is what we’re dealing with? And you’ve talked a lot about gray space; do you want to tell us a little bit more about that?
- Alan:
- Well, the grey space environment it can sometimes overlap or blend green space, and grey space, is really defined by increased transportation hubs. Factories. Commercial activity. More bars. More fast-food outlets. Greater signage on the sidewalk. It’s luring the consumer in. Eat this fast food. Take this soft drink. Increase your intake of ultra processed foods. That stuff doesn’t happen purely by magic. There are massive commercial forces that drive that person making that decision to take a food or an item, or a lifestyle that could promote dysbiosis. So again, grey space – it’s especially true as you and I have talked about many times among the disadvantaged.
- Susan:
- Disadvantaged. Yes.
- Alan:
- The most vulnerable amongst us have the highest burden. Ah for example, fast food outlets around their residence. When we talk about dysbiosis, it almost seems strange not to talk about the forces that drive it in the first place.
- Susan:
- Yes. And I think once again, when we think about the importance of early life, and all of these forces have greater implications for the developing fetus. The developing child. Throughout the early period when all of our systems, our behaviour, and our health for the future is being established, and this is really what we called the developmental origins of health and diseases. Often known as “dough head.” It’s a really important part of this conversation because it really highlights the importance of microbes and other environmental factors early on during development in terms of programming us for health that should last we hope for decades or not. So, and risk of diseases, such as heart disease, dementia or even mental health disorders may in fact be programmed really early in life.
- Alan:
- Very early in life. You’re setting the stage for what you may experience at 40 or 50 or 60 years old.
- Susan:
- So, when we come back to this concept of ah species extinction, I find it absolutely fascinating when we actually look at a genetic approach. When we look at the fecal samples, the stool samples collected from western populations and compare them to the dwindling number of hunter gatherer populations still on this planet, and we can find that, in fact, when we look at it this way, there is evidence of loss of species below a functional threshold in western population. So, this really shows us there is evidence that we are seeing ecological extinctions. Disappearing microbes. In western populations, which obviously has implications for our health.
- Alan:
- And to confirm the dysbiotic drift theory as it relates to disadvantaged communities in vulnerable populations within North America. Within westernized cultures; those who would again have those greater fast-food outlets and so forth around them. When researchers recently sampled their gut mucosal lining, they had much less diversity of microbes. So, it actually exists in westernized nations. There’s extinction as well. At least it’s heading in that direction based on lifestyle factors, and again that environmental push that we talked about.
- Susan:
- So, and just to summarize that with – as we say, “the drift” of our natural environment, towards the built environment and gray space so too, we see, “the drift” of our microbial species to diversity at the same time.
- Alan:
- Yes, that’s true.
- Susan:
- So, that’s probably a really good point to start talking about how important microbes are for human health, and one way I like to think about it is that the human body has been likened to a warm-blooded coral reef home to many vast and diverse ecosystems in all of our inner and outer surfaces.And just like a coral reef we are very vulnerable to changes in the environment.
- Alan:
- I love that. I really love the idea of the analogy of a coral reef; I think it’s so perfect. Because the slightest change could actually influence the microbiota whether its dietary or what have you. There’s a really small sort of window in there of health and life. It’s almost like a mini biosphere as well. Wonderful.
- Susan:
- And it comes back to that idea that we are what we can describe as hollow bions. We are microbes and humans together.
- Alan:
- A single functioning biological unit.
- Susan:
- That’s right. That’s right. And we are influx with our environment. We’re not a separate as we perhaps once thought. As an immunologist I find this all very fascinating. Because the immune system is, in fact, our primary – it always has been – our primary sensory interface with the environment. It’s constantly sampling the environment around us. In fact, we have cells that have actually poke their arms up and sample what’s going on in our gut, in our respiratory tract to find out what is going on and what we’re encountering. And they are very subtle and very vulnerable to subtle changes in the environment. So, our immune system is very important in raiding the environment, but also very sensitive to it. So, changes in biodiversity and in other factors will affect our immune health. And this is really important, and really important that people understand that the immune system is really everywhere in our bodies. It has a fundamental effect on pretty much every system in our body, and therefore, can influence virtually every aspect of health including our brain.
- Alan:
- Well, I was going to ask you about that. And it includes the brain. A lot of the writing that we both done has worked under the banner; there is no health without mental health.
- Susan:
- Absolutely.
- Alan:
- And it’s really important to understand that the immune system is not this little small gizmo that protects us against colds and flus. It actually has an essential role in virtually every chronic medical condition today.
- Susan:
- It is and in the initial development of our systems. Including the brain. We now know that immune cells are really crucial for how the brain develops in the first place. Which is fascinating. So, anything in the environment, which influences our immune health will have effects on virtually every aspect of our health, and that includes microbes. It includes nutrition. It includes pollution and many other factors in the environment. And if we look at all the body systems that we know we can immediately see why the immune system is important for not just protecting us from threats in the environment. It’s important for our metabolism, and microbes are very important for metabolism. Important for our cardiovascular health. Our digestion. Detoxification. Really important as we said for brain development and the actual production of neurotransmitters. Our mood. Our behaviour. Even our appetite. And our hormones. So, things that disrupt our forces and what we call dysbiosis could adversely affect pretty much all of these functions. And so, when we look at the immune system, we can see that it is immediately implicated that in the rise in so many of these chronic diseases. Because so many of them are influenced by a result of inflammation and are associated with this declining of biodiversity story. So, we are living in an age of inflammation.
- Alan:
- It was on the cover of Time Magazine. It’s got to be pushing ten years ago, the cover story, and nothing has changed since then. If anything, we’ve probably learned more. That most chronic medical conditions are highly rooted in inflammation.
- Susan:
- So, inflammation or low grade chronic inflammation really points to this central role of the immune system and everything from bowel disease to allergies, to mental ill health to heart disease. Even obesity. Arthritis, diabetes and so many of the chronic conditions in our society today. In fact, increasingly, we’re seeing studies showing that many of these chronic diseases, these inflammatory diseases are associated with reduced measures of biodiversity when we take the stool samples from these patients. We can see there are again associations. We can’t prove causality. But they appear to be increasing associations with reduced or altered biodiversity.
- Alan:
- So, that general rule again external environments typically really healthy if they’re biodiverse. And the same thing seems to be applying to resiliency against many chronic medical conditions. Diversity is protective.
- Susan:
- Absolutely.
