WASN: From a high level perspective, what is the microbiome, and why have you made it your life’s work?
AK: The microbiome is the collective genetic material of all the microorganisms (mostly bacteria, but also fungi, protozoa, and viruses) that live in and on your body. They constitute approximately 50% of you by cell count—an invisible, but powerful half. The microbiome, which scientists are referring to as our “lost organ”, is redefining health and radically transforming our approach to medicine, hygiene, diet, living, and the choices we make for ourselves, our children, and our planet.
WASN: What do we know about the role of the microbiome on human health and wellbeing?
AK: The microbiome plays a systems-wide role in the human body. There’s almost no function in the human body that our bacterial symbionts and their metabolites aren’t connected to. Let’s start with what you’ve probably already heard of—your gut. Trillions of beneficial bacteria reside along your epithelial wall and (partly by sheer strength in numbers):
maintain your gut barrier integrity, making it difficult for inhospitable bacteria to penetrate.
maintain an acidic environment to dissuade certain alkaline-loving pathogenic bacteria from taking root.
support the secretion of intestinal mucus and collaborate closely with your gut’s ‘gatekeepers’ (tight junctions) to modulate what should (ie. nutrients) or shouldn’t (i.e. undigested food particles or pathogenic bacteria) pass through to the body.
And certain bacteria even produce neurotransmitters that stimulate muscle contractions—yes, we’re talking about pooping.
When we eat, certain microbial genes code for enzymes that break down food we otherwise couldn’t—think complex carbohydrates, like fiber. Through this process, bacteria also produce short-chain fatty acids like butyrate, which fuel the cells lining your colon and strengthen your protective intestinal mucosa. Butyrate, specifically, has powerful anti-inflammatory effects beyond the gut, reducing oxidative stress (imbalance between free radicals and detoxifying antioxidants) and managing the production of regulatory T-cells (the ones that help your body distinguish between self and intruder).
Beyond this, bacteria also synthesize essential vitamins B and K, defend against E. coli and other intruders in the urogenital tract, and for women, balance pH and protect from unwanted yeast in the vaginal biome. Their health is critical to the health of our entire body—from heart to skin to metabolism to immune function.
All this to say that our bacteria play an incredibly complex and critical role in helping us thrive. Scientists are consistently discovering new associations between our microbiome and our health. For example, new findings around the gut-brain axis are emerging which indicate that our gut flora may even impact our mood, appetite, behavior, and circadian rhythm—functions we previously thought were relegated just to the brain.
WASN: What is a recent discovery in human microbiome research that gets you super excited?
AK: In November of last year, a tentative finding uncovered an exhilarating and unexpectedly intimate relationship between microbes and the brain—and the possibility of a ‘brain microbiome’. Neuroanatomist Rosalinda Robert's lab at the University of Alabama in Birmingham examines the differences between healthy subjects and those with schizophrenia through identifying differences between slices of brain tissue preserved in the hours after death. Five years ago, an undergraduate in the lab saw unidentified rod-shaped objects that would show up in finely-detailed images of these brain slices. The team dismissed them at first, but they would persistently show up. This year, through consultation with colleagues at UAB, it was unveiled that they were bacteria.
To date, the team has found bacteria in every brain they’ve checked—34 in all—about half of them healthy, and half from people with schizophrenia.
Until now, we believed the blood-brain barrier was impenetrable, and that if it were, it would cause life-threatening inflammation. But this preliminary finding, if confirmed, would vastly shift our understanding of how microbes can coexist and interact with our brain, and potentially even regulate its immune activity.
WASN: What is one misconception about our microbiome you wish more people knew?
AK: Most people associate the microbiome with gut health, and with good reason—the majority of these 38,000,000,000,000 microorganisms reside in your gastrointestinal tract. But what many don’t realize is that there are also diverse communities of microbes residing in places like your mouth, your skin, and your armpits. And just like in your gut, the delicate balance between host (human) and microorganisms is responsible for a healthy ecosystem.
On your skin, for example, synbiotic bacteria occupy a wide range of skin niches, protecting against invasion by more pathogenic ones (i.e. the acne-causing Propionibacterium acnes). Others play a role in educating the billions of human T cells, priming them to decipher between friend and foe and respond appropriately to pathogens. And just like in the gut, perturbations (both internal or external, like genetic variation or cosmetics or excessive use of hand sanitizers) to this ecosystem can manifest as consequences to our skin health.
WASN: What are the best ways to take care of our microbiome?
AK: In 2007, the National Institutes of Health launched the Human Microbiome Project. Backed with $173 million in funding, it was tasked with the goal of characterizing the human microbiome to determine if changes in microbiome composition could be linked to health and disease. The project encompassed five years of research and over 200 scientists, and concluded in 2012 that there is no universally healthy microbiome. Like your genome, your microbiome is entirely unique to you. And it’s changing, constantly. External factors like diet, exercise, medicine, and even sleep, can all impact and alter the composition of your microbiome on a daily basis.
The one thing we do know is that scientists view diversity (of the species within you) as a marker of health—makes sense when you think about the importance of biodiversity in any ecosystem. While the research is early, scientists have seen a universal association between loss of diversity and disease—autoimmune, allergies, autism, asthma, diabetes, obesity, and more.
When it comes to the health of your microbiome, what you can ask is this—are my bacteria working optimally with my body to perform the functions critical to my health? How can I support my microbiome in the daily choices I make? Is the antibiotic my doctor just prescribed absolutely necessary? Am I eating for myself or also for my 38,000,000,000,000 within? Am I getting enough fiber? Should I be incorporating probiotics and prebiotics into my routine?
When it comes to diet, most people don’t eat enough fiber, which is critical to the health of your microbiome. In the past year, compelling research has shown that it’s not just about eating a mostly plant-based diet, but also the diversity of those plants—so consume as many different vegetables as you can each week versus being a kale creature of habit.
A few simple guidelines to diet, through the lens of the microbiome:
high abundance of diverse source of plant fibers and polyphenols (like vegetables, walnuts, pomegranates, berries, and green tea)
high in fiber and microbiota-accessible carbohydrates (like broccoli, brussels sprouts, beans, and sweet potatoes)
high in Omega-3 and monounsaturated fat (like salmon, sardines, avocados, and olive oil)
low in sugar, preservative agents, processed foods, food additives
low in saturated fat (encourages growth of fat loving bacteria)
low in animal protein
Common culprits that perturb the microbiome include:
Western diet (high intake of red meat, processed foods, fried foods, high-sugar foods and beverages, and refined grains)
Antibiotics / Antibacterials
NSAIDs (i.e. aspirin and Advil)
WASN: You’ve shared your belief that science is inherently a spiritual practice—can you share more about that perspective?
AK: The scientific method, much like spirituality, is a framework of questioning and a catalyst for deep knowing. It is a methodology for experimentation with no attachment to outcome (hypothesis > experiment> observe > learn > iterate). That it’s been conflated with Western medicine or big pharma is a disservice to its origin, how it’s shaped our world, and its potential. We are in a moment where what is fact and truth is called into question every day—and while all methods have their flaws when put into human hands, I find science is more Buddhist and grounded in non-attachment than many of the expressions of spirituality I am exposed to daily.
WASN: When it comes to microbiome research + product development, what are you most excited to delve into in the next 5-10 years?
AK: The connection between human and planetary health and reconciling them as one—the microbiome is a pathway for this. The microbiome offers an entire perspective shift, a profound new lens through which to see (or unsee) many long held truths and to harness that new perspective to develop solutions to many of the biggest problems facing our collective health.
WASN: How do you tap into the power of curiosity in your daily life?
AK: I ask questions. A lot of them.