‘What to expect when you’re expecting to grow old’: An interview with Whole Body Microbiome co-authors, Drs. Jessica and Brett Finlay

As microbiome science advances rapidly, the number of books on microbiome-related topics is growing—yet it can be difficult to find reliable, science-based information. The hottest new microbiome book not only contains robust scientific information, but has suggestions on how to apply the findings throughout the lifespan: The Whole-Body Microbiome, written by Microbiome Insights co-founder Dr. Brett Finlay, along with his daughter Dr. Jessica Finlay, an environmental gerontologist.

The new book is a practical take on how to use the latest knowledge about the microbiome for healthy aging, with the father-daughter pair offering perspectives from multiple scientific fields and different points in the lifespan. Jessica Finlay brings to bear her pioneering work in the area of ‘applied clinical geography’, while Brett Finlay (a recent Canadian Medical Hall of Fame inductee) brings decades of insights gained from his scientific work in medical microbiology and immunology.

In this interview, the Drs. Finlay describe how their personal worlds were changed by their knowledge about the human microbiome—and how their book can be put to use, not only by members of the general public, but also by fellow scientists and medical professionals.

What gap did you hope to fill by writing this book?

 JF: What to expect when you’re expecting to grow old? While there is an entire industry devoted to preparing expectant parents, scant resources guide us on how to grow old. This is especially true if you’re looking for scientifically-based, accurate information to inform lifestyle, diet, household, and health practices. The major gap we aimed to fill was scientifically-based knowledge on aging and longevity, distilled for a wide audience. The microbiome’s effects on healthy aging has not yet been covered in popular literature.

While there is a lot of hype about the gut microbiome, we in fact know that microbial communities all over our bodies affect how our brain, teeth, skin, heart, gut, bones, immune system, and nearly every other body part functions as we progress through life. Our wellbeing is also intimately to the microbes that surround us – on our cellphones, kitchen sponges, houseplants, pets, and desks. In the book we take a holistic approach to the microbes in and around us (not just in the gut) to explore how they are integral to a healthy and long life.

We focus on aging as a lifelong process in Whole-Body Microbiome. You don’t just suddenly ‘flip the switch’ and become old at, say, 65. We accumulate health risks and liabilities throughout our entire lifetimes. The book offers lifestyle strategies and “quick tips” that we can all take advantage of, whether we’re eighteen or eighty.

BF: Having already written a book for parents on early life microbes—and not getting any younger—we wanted to discuss microbes and healthy aging. It was important to us not just to focus on ‘the elderly’, but on the entire aging process, which includes adults of all ages.

What are a few of the main messages in your book?

BF:  We live in harmony (usually) with our microbes, and they play a much larger role in our body’s functions than we once thought.  By paying attention to our microbes, we can have significant effects on many aging processes.

JF: Yes, the first main message is to embrace our microbes! They are lifelong partners who are heavily impacted by our lifestyle decisions, and necessary for our health and longevity.

We detail three overarching strategies that intertwine healthy microbes and healthy aging:

(1) Consume a balanced diet filled with fiber (e.g., fruits, nuts, vegetables, whole grains, berries), fermented foods, and limited meat and refined sugars.

(2) Stay active: This doesn’t necessarily mean marathon training, but rather moving around regularly throughout the day, engaging in varied aerobic and strength activities.

(3) Stay engaged with others: Regular social contact with family, friends, and extended networks is important for our wellbeing – and our microbes as well! We deposit, swap, and share microbes every time we shake hands, hug, play cards, eat communally, and share spaces.

As scientists, how has the microbiome changed the way you think?

BF:  I now see the world through a veneer of microbes! Even though we can’t see them, they are there and can affect many things.

 JF: My outlook on the world has also shifted: I now pause to consider my microbes when shopping for groceries, brushing my teeth, sending a text message, washing my hands, talking to my doctor, hugging a family member, going for a run, and gardening.

I also now see microbial connections in my research as an environmental gerontologist: when I consider the level of cleanliness and sanitization in a private home or assisted living facility; microbial exposures in later life through pets, socializing, hospitalizations, and even houseplants; and everyday diet, lifestyle, and health habits that impact older people’s microflora.

How can your professional colleagues make use of this book?

BF: It is based on peer-reviewed science, so scientists will appreciate it. They can use it for their own personal improvement, or if they specialize in one area, they can get a broad overview of the wonderful and amazing invisible world of microbes that live in and on us.

JF: We distill peer-reviewed scientific research and include interviews with leading scientific and medical experts in each chapter. Taking into account the rapid scientific advances and exploding knowledge, we take the current ‘pulse’ of microbiome research as it relates to adult health and longevity.

In addition to providing relevant information that can inform personal health and diet/lifestyle decisions, we aim to inspire our professional colleagues and fellow scientists to keep pursuing this fascinating and important area of research. This includes figuring out specific microbial genes and mechanisms responsible for particular effects in and on our bodies. We need more studies and data!

What tips do you have about microbiome-related science communication?

BF: Some of us scientists work with microbes and see evidence of what they do every day. But most people have a hard time appreciating microbes because they can’t see them. Convincing people of the invisible is hard. However, we know they have profound effects on both health and disease—and it is these aspects that we can focus on.

JF: There is a lot of hype and misinformation surrounding microbiome-related science: from misleading websites, to health claims (say, for probiotics) not supported by adequate clinical trials. It is important to be clear about what statements are supported by rigorous science, what statements are ‘not quite there yet’ (in terms of extrapolating findings from existing data), and what statements are downright wrong. This was an important task for us when writing the book. Beyond this, we recommend directing audiences to valid sources of information, such as PubMed and other academic search engines, for peer-reviewed articles/reviews, to stay informed.

 

Novel combination of techniques improves identification of soil bacteria involved in wood decomposition: The latest from Mohn lab

In a bid to overcome the limitations of what scientists found previously from culture-dependent studies, new research shows stable isotope probing, coupled with next-generation sequencing techniques, can be used to identify which organisms living in the complex microbial soil community are involved in the decomposition of lignin, cellulose, and hemicellulose–three major polymers that make up wood.

Researchers from the lab of Bill Mohn (Microbiome Insights co-founder) at University of British Colombia labelled the lignin, cellulose, and hemicellulose of wood samples with a carbon isotope and allowed the process of decomposition to proceed in experimental microcosms. Subsequent amplicon and shotgun sequencing of the microbial communities in the microcosms: first, identified the organisms present without the use of cultures; and second, by measuring the total assimilation of the carbon isotope into the DNA of the sequenced amplicons, identified which species were involved in decomposition. This method greatly improves the understanding of the species and genes involved in this essential process — an insight not possible with standard culturing methods.

Forest soil decomposition of wood is a major global carbon sink, making it important for the study of climate change. To date, researchers knew microbes must be involved in helping fungi, the main drivers of wood decomposition, in the task of recycling this material but were limited in the ability to identify those involved.  This was mostly due to the fact that many bacteria cannot be grown on cultures in the lab. This new approach not only removes this barrier but also, due to the ability of metagenomics to work with pooled samples, provides a glimpse of the entire community in the sample —providing a more natural representation of the forest communities.

The researchers found that bacteria, specifically Gram-negative types from the families Comamonadaceae and Caulobacteraceae, were more involved in lignin degradation, with fungi taking on a prominent cellulose degrading role. Interestingly too, most species incorporated a carbon label from a single lignocellulosic polymer, strongly suggesting specialization among the microbes involved.  Furthermore, they found that variations in the community compositions across different soil types and soil layers constrained the degrading activity. According to the researchers involved: “the relationship between these communities and process rates should receive continuing study to refine our understanding of soil carbon stabilization and terrestrial carbon cycling models.” Additionally, the newly discovered sets of  gene clusters involved in the degradation process provide “a trove of potentially novel enzymes for biotechnological applications.”

This study was recently covered in Chemistry World.