Sustainable Agriculture: Gut feelings

I like to think of myself as more than just human. It’s not that I have super powers or robotic limbs, but rather that my body can be considered an ecosystem in itself. New research on the microscopic organisms living inside and on our bodies has painted humans as human/bacteria/fungi superorganisms. Such a shift in self-identity has made me reconsider the sterile, Western lifestyle that I was raised with. From hand sanitizer to antibiotics to processed foods — I find myself asking why have I been enlisted in this invisible war against germs, and when can peace accords begin?

Such questions were first borne by the Human Genome Project, an international, collaborative, biological experiment started in 1990 that aimed to sequence the entire human genome. When the project was imagined in the 1980s, researchers hypothesized that the human genome would be made of nearly 100,000 genes. The hypothesis reflected our own anthropocentric ideas of ourselves as magnificently complex organisms. The results of the project actually found that the human genome consists of about 20,000 protein-coding genes, which researchers have remarked is not too different from a fruit fly.

If our genomes are not as intricately complex as we once thought, then what accounts for the differences between humans and the creatures circling above our week-old trash bins? This question then spawned a research project called the Human Microbiome Project that is examining the organisms that exist within our body — sometimes called our “secondary biome” — that may be responsible for the complexity of our species.

Microbiologists around the world are beginning to sample and sequence the bacterial communities within our bodies to determine what a robust and balanced microbiota looks like. Because research and analysis in this field has just begun, scientists are wary to raise any definitive flags on the links between the human microbiota and health, environmental toxicology, medicine or food.

However, some overall trends are becoming clear that make us revalue conventional wisdom. The adage “You are what you eat” might soon be reworded to “You are what eats what you eat” when you consider that much of our diet is only beneficial if the bacteria inside our gut prefer it.

Researchers in Brussels have succeeded in reproducing inflammation in mice fed “junk food” similar to that of inflammation in obese individuals. The junk food diet feeds a select population of gut bacteria that thrive on those foods while essentially starving out other bacteria that thrive on food sources like fiber. The bacteria that are starved out in our junk food binges are often the ones that help maintain balance within our guts and digestive systems.

Additionally, researchers from Washington State University have evidence that supports that plants grown in soil with a rich microbiota will produce food that has more antioxidants and phytonutrients than their conventional counterparts. The controversy over the link between soil health and nutritional quality is well-placed, because it would support the argument that organic practices are not only better for the environment, but they are better for our health, too.

What if we extended the logic that “quality ingredients produce quality end products” to soil? Soil is unmistakably an ingredient in the production of our food. It is not merely a container or holding space from which the food bursts forth, but rather a vital component.

The work of the Human Microbiome Project and associated inquiries is pushing us to redefine the limits of ourselves. If the soil becomes part of the plant, and the plant becomes part of the microbes in our gut, then through the transitive property of equality, soil is a part of us.

It helps me to imagine my gut fauna as a social network. When I eat processed foods that lack a diversity of microbes, the bacterial party inside my body turns into one of those awkward gatherings with only a handful of attendees. But when I garden outside, interact with animals or eat fermented foods like yogurt and miso, I am essentially enlivening that same bacterial party with a diverse guest list and bumpin’ tunes.

To be invited to one of ELLEN PEARSON’S bacterial gut parties, email her at erpearson@ucdavis.edu.