Unseen – a quiet battle rages in a hidden ecosystem. A tiny creature forages among its colony, creating chemicals meant to deter any would-be interlopers that get too close. A fast-moving predator searches for a meal, groping through the darkness for its prey. Different species help or harm their neighbors – whole food chains dependent on a careful balance of resources. New species arrive, spurring fresh competition or collaboration among the members, swathes of territory quickly exchanging hands as the conflict rages on. Times of feast or famine lead to a reshuffling of the natural order – the emergence of new populations and the disappearance of others – and the cycle for dominance begins anew. I’m speaking not of vast, glittering oceans or towering, primordial forests – but of the alliances formed, battles waged, and delicate balances maintained, all within the ecology of the human gut.
Survival of the fittest
Most people could tell you that the gut microbiome – the community of microorganisms inhabiting the human digestive tract – is vital to human health. Over the years, scientists have become increasingly aware of the important role it plays in how we digest our food, acquire nutrients, and stave off disease. But what exactly does ‘maintaining’ your microbiome actually mean? Why are some bacteria good to have, and which ones are bad? What do probiotics, prebiotics, and postbiotics do, and how are they different?
The common refrain of ‘good versus bad gut bacteria’ is sometimes something of a misnomer – just as massive booms in the numbers of a specific flower can make it a weed, the overpopulation of certain bacteria strains can send a carefully balanced system into chaos.1 Within our bodies – this can mean bloating, digestive issues, food sensitivities, and a host of other problems affecting overall quality of life. Just as with any other environment, when you have a diverse number of species all working together and in competition with each other, their populations tend to be somewhat balanced by the others – aiding in the overall health of the gut and making up its unique ecology. Dysbiosis refers specifically to the disruption of this diversity – when so called ‘keystone’ species start to vanish, or when species largely harmless in smaller amounts grow suddenly in population. Building and maintaining a good microbiome isn’t just a matter of having a single ‘good’ bacteria, but of fostering a thriving, rich, and diverse ecosystem.
Inside our guts, these tiny turf wars take place in extraordinary numbers, each species hosting its own arsenal of tools. Some bacterial species, such as the beneficial Lactobacillus, expel large amounts of acid, lowering the pH around itself to make the area inhospitable to potential pathogens as it grows, also resulting in the characteristic sour tang of yogurt.2 Other bacteria pass along nutrients, such as fiber or polyphenols, down a ladder of transformation – the biproducts of one group’s feeding frenzy going on to feed another, until at last, the final product of the chain, harmful or beneficial, is taken up by the humans hosting them. Some bacteria even act as predators, such as Bdellovibrio bacteriovorus, a species which actively attacks and invades other gram-negative bacterial cells, such as the sometimes pathogenic E. coli.3 The result of these interactions actively creates the microbiome, and the ‘winners’ and ‘losers’ of the resulting competition can contribute to everything from our daily mood and weight4, to our food cravings5, to how well we absorb specific vitamins and nutrients6 and regulate our immune system.7
Depending on what bacteria we’ve been exposed to, what we eat, and what bacteria we already have present, the microbiome is completely unique from person to person, and can be compromised of up to hundreds of unique species.8 Despite the fact our microbial allies have always been with us, science is still continuously learning about all the effects the microbiome has on human health and wellness, and how to continue to harness it. Verb Biotics, with its function-first approach, not only prioritizes finding new and innovative biotics to add to this system – but enriching and supporting the microbiome each of us has naturally cultivated from birth.
Creating a Microbial Garden
So how can a person foster good microbial diversity? One way is to consume probiotics – living bacteria that pass through the gut. Probiotics may be particularly important to those who currently lack microbial diversity or who have recently taken an antibiotic, reducing the diversity of their microbial populations. Depending on the particular makeup of a person’s microbiota, these new organisms may temporarily colonize the gut, thus potentially adding to the total diversity present. Because microbes are in constant competition with one another and attachment is not guaranteed, taking a probiotic frequently gives bacteria a more ample chance to linger, and pass on any beneficial effects they may offer.
As we’ve expanded what we know about the gut, so too has our understanding of how to ‘tend’ to our microbiota improved. Postbiotics are substances that contain a bacterially fermented product which is then inactivated by pasteurization and can be used by other bacteria – skipping a link in the microbial ‘food chain’. Think of this as similar to adding compost from food scraps to your garden – it is essentially an act of reintroducing nutrients to a system to be snapped up by its residents, as opposed to simply adding more “seeds”. While a new species is not introduced, postbiotics can help the beneficial microbial species that already exist in your gut flourish and proliferate in greater amounts. If we continue with the analogy of a garden, then prebiotics, in contrast, are akin to fertilizer. When introduced, they can help your native ecosystem grow and produce a larger yield of beneficial compounds – acting as ingredients to be transformed into a helpful product by the bacteria present.
As human understanding of the gut microbiome and its relationship to our health has improved, a picture of a rich, diverse environment of competition and interdependence has become clear. And just as every human is unique – so too is the composition of the bacterial community that exists inside them. So next time you take a Verb biosolution, drink some kombucha, or eat yogurt, get excited! Not only are you helping your gut bacteria– you’re tending to your own, personal microbial garden!
About the Author: Claire Highsmith is an Associate Scientist at Verb who has been working in the Biotech industry for the past three years, with an additional three years’ experience in science communication. Her research interests include the effects of microbial diversity and ecology on their host organism, and the isolation and identification of bacteria present on diverse natural sources, including wild and foraged foods.
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