Yes, I know… here I go talking crap again. My favorite topic. And I will even go further by boldly stating that poop will be greatly talked about over the next years, as the practical applications of microbial feces analysis become available to the general public. One thing is clear, the life in our poop is an essential part of each one of us… and may define our interpersonal differences more than our own genes. Interested yet? Do read on!

There are approximately 1.5 kg of bacteria in each of our guts, representing roughly the same number of cells as our own human cells (30 trillion human and 39 trillion microbial). These bacteria, often termed the gut microbiome, come from various species and express between 2 and 20 million genes, in comparison to our 20 000 human ones. Our own DNA is 99 percent identical between us in comparison to our microbiomes, which can be as low as 10% alike between individuals.

Model mice experiments clearly indicate a link between our microbiome and many health-related factors, such as auto-immune diseases (multiple sclerosis, type 1 diabetes, Crohn’s disease), autism, depression, and obesity. Also, it is becoming very clear that our microbiome affects how our bodies respond to drugs, including Tylenol and cancer drugs. In many cases, microbiome genes are much better markers for a health condition than our own genes. For example, our own genes are 57% accurate as markers for obesity, whereas the microbiome provides 90% accuracy.

When it comes to the microbiome, environment dominates over genetics… This simply translates into “what we are exposed to in the natural world and what we eat counts a lot”. This means that a significant amount of power over our health is on ourselves, which is very positive from my perspective. In practice, I also like the message:  Get dirty sometimes and enjoy wholesome foods loaded with plants (ideally, often taken directly from a tree or a plant that has not been doused in pesticides). See what wonderful fruits and vegetables are in season this summer and take time to shop for a rainbow in plant foods. A healthy life means a healthy microbiome.

note: this piece was originally published in the Summer 2019 issue of the Best Health newsletter (


  • Sofia C. Pereira

    PhD Biology, Genetics I Evidence Based Health Coach, Writer

    I am a certified health coach (Institute for Integrative Nutrition, New York) with a PhD in biology/genetics (Toronto, Canada) and use an integrated scientific approach towards maximizing health and wellness. I believe that everyone can live their best possible lives by eating well, sleeping well, moving their bodies, constantly testing their personal limits, being open to love, respecting their instincts, having a curious mind, and being authentic. In my book - The Food Anthropologist - I log a one year journey through twelve consecutive 30-day food challenges, including gluten and dairy free, ketogenic, vegan, macrobiotic, paleolithic, and intermittent fasting. Incredible how 365 days of food and drink limitations can translate into lessons for life. More information at