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The Headlines

Trust Your Gut

Our gut bacteria are powerful—it's time to start listening

Prof. Paul K.S. Chan <em>(Photo by ISO Staff)</em>

Diabetes, obesity, hypertension and depression persist as pervasive ailments of modern society. The health assumptions we draw seem to push us, almost instinctively, toward the pill cabinet. Prof. Paul K.S. Chan, Associate Director of the Centre for Gut Microbiota Research, suggests otherwise: we must first look inwards before seeking external solutions.

Professor Chan is Chairman of the Department of Microbiology at the Faculty of Medicine in CUHK. As an expert in clinical virology and epidemiology, he has become one of the foremost researchers in gut microbiome (‘gut microbial function’). Rather than adopting the assumption that health issues invariably stem from ourselves (our own cells), Professor Chan posits that the crux is gut bacteria imbalance. Finding the panacea to our most prevalent diseases may lie in balancing our gut microbiome.

While gut bacteria of healthy populations are generally well-balanced, evidence points to a correlation between disease—both mental and physical—and a disrupted gut microbiome. Professor Chan’s 2018 pilot study included over 400 subjects and established five categories for bacterial patterns. Using stool bacterial compositions, it marked the first time categorical differences in gut health emerged and gut microbial profiles were set.

Gut health lies furtive; it touches more dimensions of our lives than conjecture would lead us to believe. Chronological age influences the gut microorganism, though it is just one piece of a multifaceted puzzle. Older individuals may have different patterns than younger individuals, though to ascribe disparities entirely to age is untoward—diet, lifestyle, environment, and genetics have a say too. The pilot study found evidence suggesting a correlation between gut health and aspects such as sleep quality, mood, blood pressure, mental health, antibiotic usage, and metabolic syndrome.

Even subtle, more unassuming factors such as marital status and mode of birth (cesarean section versus vaginal delivery) revealed correlations. A single individual living alone exhibited a disparate gut microorganism pattern compared to an intimate partnership co-inhabiting a single household. The dissimilar yet patterned characteristics that distinguish between cesarean section births and vaginal delivery births provides further intrigue—how could a baby’s very first step into the world hold sway in the future of their gut health?

Given the aforementioned, an ideal portrait of gut health remains vague; this is a relatively new field of study. These preliminary observations bode well for the future of disease prediction and preemptive intervention. ‘Until we can determine what a normal healthy gut microorganism pattern looks like, we cannot begin to recommend specific, individual interventions,’ Professor Chan explains. ‘Once we establish this, we can develop predictions and implications regarding health advice. The first step is determining where an individual stands on the map of gut microorganisms.’

An evidence-based goal is the first step towards widespread, improved health and awareness. Once a typical, healthy gut microorganism is discovered and put in place, examinations can proceed to determine whether a given individual deviates from the baseline.

What’s Good About Bacteria?

We grow up viewing bacteria as the antagonist to everyday life. We wash our hands incessantly, avoid eating uncooked meat, and abide by the five-second rule when we drop a cookie on the floor. 'Bacteria is bad,' we say. We rid ourselves of bacteria with hand sanitizer and antibiotics.

Professor Chan works against this conventional stigma, ‘We have learned we have good bacteria. Organisms exist in our gut that we cannot survive without.’

Our gut operates with innumerable variations of bacteria, many of which are highly functional and essential; in other words, good. Oftentimes, our health issues stem not from pathology or disease of our own cells, but rather an imbalance of our gut microbiome.

Step into the Future

More and more maladies continue to be linked to gut health as research advances. Colon cancer, mental illnesses, diabetes and a slew of allergies only scratch the surface of a laundry list of ailments stemming from abnormal or imbalanced gut microorganism compositions. Defining reference points for gut health improves the chance for anticipatory and personalized interventions while potentially limiting surprise onsets of disease.

These considerations will continue to play a role in Professor Chan’s forthcoming research. In May 2019, he plans to establish a gut microbiota data bank specific to Hong Kong by recruiting 3,000 volunteer subjects. Entitled ‘HKGutMicMap’, the project focuses on establishing the baseline, normal pattern of a healthy gut microorganism profile for Hong Kong people. As the 2018 pilot study revealed, lifestyle and environment both impact the gut microbiome. To establish an accurate and relevant gut microorganism profile, the study must be population- and geography-sensitive, hence the focus on Hong Kong residents.

By painting a picture of what a healthy gut looks like, Professor Chan hopes to establish an applicable, attainable health target for people living in Hong Kong. A baseline gut pattern marks the first step towards providing a goal and strategy towards more holistic wellness.

Listen to Your Gut—Answer the Call!

As with any pursuit, having a target precedes intelligent action. In the medical field stakes are heightened, making Professor Chan’s research as necessary as it is groundbreaking. Without this study, people stand without a direction to aim in to remedy their gut health.

The study, however, cannot proceed without participation from the public. ‘This research is unique to each population, so we need people in Hong Kong to come out and contribute. Volunteer for this study to set the course for medicine in the future,’ adds Professor Chan. ‘Provide a small thing now so future generations can enjoy the progress of research.’

Because of the distinction of gut patterns between populations and geographies, there cannot be a substitute for Hong Kong people. Data from other countries’ research cannot replace this study. Studies from North America and Europe can be useful for other medical fields, though the uniqueness of gut health precludes borrowing data.

Professor Chan’s gut health study begins 1 May 2019. Participants will visit the Prince of Wales Hospital to complete a health questionnaire and assessment, provide skin swabs, oral samples and a blood test. The final step will be to collect stool samples for bacterial analysis. Each participant will receive a travel allowance and a comprehensive health assessment report.

The field of gut health research remains in its incipient stages, and Professor Chan is spearheading these next steps. If progress continues at this rate, administering health interventions on an evidence-based, preemptive basis will be within reach. Hopefully in the not-so-distant future, treatment plans for cancer, diabetes and other afflictions will trend towards the predictive and prophylactic, rather than the reactive and palliative.

The gut health expert was optimistic regarding the potential for predictive health interventions. ‘This will be in the near future. Years time. Not decades. Things are moving quickly,’ says Professor Chan.

To solve our most prevalent diseases we may just need a gut check.

Phil Rosen

This article was originally published in No. 538, Newsletter in May 2019.

Paul K.S. Chan gut bacteria microbe HKGutMicMap professors Centre for Gut Microbiota Research Department of Microbiology Faculty of Medicine