When Eugenia Bone cooks, it’s not just about putting food on the table. It’s about invoking the Italian heritage her James Beard Award–winning chef father passed down when he grilled duck breast on chilly fall nights. Or the connection to the rest of the unseen world she felt when she stumbled upon wild mushrooms in the Colorado wilderness for the first time. Over the years, her cookbook-memoir hybrids have brought this sense of wonder, culture, and context to the culinary realm. Now she’s applying those same sensibilities to science, with her new book, Microbia, which delves into the world of microbes.

The book follows Bone, who typically splits her time between New York and the tiny western Colorado town of Crawford, as she enrolls in an environmental biology course at Columbia University—essentially heading back to college at the age of 55. What comes next is a wonderfully engaging journey as Bone realizes that the entire world is dependent on minuscule organisms we often label as dangerous or write off as unimportant. From submitting a poop sample to a research institute to attending a conference filled with geeky, intimidating researchers, Bone translates wonky topics into relatable experiences that make microbiology seem surprisingly approachable. We chatted with her to get the dirt on tackling college in middle age, how the Centennial State influenced her book, and why microbes might just save us all.

5280: What compelled you to write a book about microbes?

EB: When writing Mycophilia, my book about fungi and mushrooms, I got really interested in this idea of endophytic fungi—the fungi that live within the cells of all plants. I was like, ‘You mean there’s a fungus living there happily? The plant wants them there?’ I thought that was extremely curious. And I was captivated with all the new stuff just beginning to come out about the gut microbiome. This was in 2010. I was thinking, ‘Wow, we’ve got microbes that help us with nutrition and provide us with immune function—helping us eat and avoid being eaten—and fungi do the same thing in plants.’ There’s some kind of pattern here, some model that keeps being repeated over and over again. What’s the connecting point? What do all these patterns have in common? It’s microbes.

There are so many fascinating little tidbits in this book—I think the most interesting one to me was that babies are more susceptible to asthma and other conditions if they’re born by C-section because they don’t get exposed to the bacteria in their mothers’ micobiomes. What were the most surprising or intriguing facts to you?

Of course, there were quite a few. I’ve been thinking lately about what are the 10 insights that really blew me away, that I want everyone else to have as well. The first was that bacteria and archaea, the prokaryotic microbes, the ones without a nucleus, they bridge the living and the non-living worlds. And then moving on, we didn’t evolve away from bacteria and archaea, the prokaryotes, they have been with us all along, at every stage in our evolution. Or ultimately realizing that something like your health is a reflection of ecological stability in your gut. ‘Oh, so I’m like a park; should I be like homosapien park of Eugenia Bone?’ That was mind-blowing to me.

We’re raised to think of bacteria as bad things—organisms that spread germs and make us sick—but you reveal that they do so many positive things as well. How did the negative perception of them come about?

Early on, the Dutch were making little lenses and looking at a raindrop and seeing all these critters living in it. That was benign observation, but soon after, doctors like Louis Pasteur started to notice that the cause of disease were these organisms. That pretty much defined bacteria up until recently. Really, it’s only in the last 20 years that researchers are beginning to say, ‘Wait a second, what are all these microbes doing in our gut? Why do they make us healthier?’

Why is it so important for us to understand microbes?

In terms of health, if people understand how many useful, important organisms are there that are necessary for the health of everything on the planet, then I think maybe the public would be a little more conscientious about the use of antibiotics and running the risk of undermining bacterial diversity, which we need for health and well-being. It’s also important to understand the moral relativity of the bacterial kingdom or the bacterial world because it’s key to appreciating that life is more complex. We are dependent on more things than our vision allows.

You mention briefly the consequences of climate change on bacteria. How serious are those ramifications?

If the last tiger killed the last elephant on the planet, it would be a tragedy, but life would continue. If the last sulfur-oxidizing bacteria was to die, the planet would shut down. Life on earth would shut down. It would be an interesting argument to say that the microbial keystone species are important on an even wider level than the keystone species in other habitats. You lose the wolves in Yellowstone Park and the park falls apart, that’s bad. But if you lose keystone bacterial species, then huge chemical systems on the planet fall apart. If we can communicate how important microbial life is to the chemical systems of the planet, these really basic things like oxygen, CO2, nitrogen fixation, temperature, if we can get that across, maybe it’ll spook people.

OK, we have to talk about the elephant in the room—the poop samples.

I thought for sure Edward’s [my father’s] poops were going to be incredibly diverse, full of fiber, like an Amazonian tribesman, because of the way he eats. They were more like the prime minister of France. The main takeaway is that you can’t just have vegetables for lunch every day and make this small change and expect these bacteria species shifts. You have to do it forever—and you have to start young. Microbes want to fall back into the roles they’ve been playing for a long time. That idea led to a deeper understanding of what kind of bullshit so-called probiotics are.

Most of the narrative of this book took place in New York, but you split your time between there and Colorado. Did our fine state influence Microbia at all?

I was in New York City my whole youth, until I met my husband, Kevin, who’s from Colorado Springs. Before I met him, the highest altitude I’d been to was the top of the World Trade Center. I credit the natural world experience that I got by living in Colorado with all my subsequent interest in nature. It was when I went to Colorado and started seeing mushrooms everywhere that I said, ‘Wow, what’s happening here?’ Otherwise I would still have been writing about movie stars or something. It led to me getting involved in everything that couldn’t be seen, but I started with sights that were the most huge and grand—and that’s the state of Colorado.

Do you have any plans for another book in the science space?

Kind of. There’s this little German study where they took all the bacteria out of the fecal transplant soup, leaving little metabolites and viruses, which are super tiny, and the fecal transplant still worked. The takeaway is it’s the viruses, which are the main predators of bacteria, that are key. Then I was like viruses are the most numerous things that are sort of alive but not alive according to our definition on Earth. There are billions and billions, countless more than bacteria, and yet we don’t consider them alive. So part of me wants to know if there is a new definition of life out there that can include viruses. A definition of life that includes more things sounds to me like the ultimate connection. But in all honesty, I’m also probably going to write another cookbook. I’ve been gathering data from Edward, my dad, for the last five years, where I write down everything he cooks and eats every day. He’s 91, so it’d be how to cook so you live to be into your 90s.

Would you ever go back to school again?

Going back to school is a little bit like going to the gym. You’re like, ‘I really don’t want to go to the gym today,’ but you go to the gym because you’re a grownup and you know from experience that you’ll feel better afterward. I could definitely go back and study again under any circumstances—I wouldn’t need to be writing a book to do it. In the beginning of the book, there’s a little inscription that says ancora imparo. It translates to I keep learning, I never stop learning. So yeah, I’d go back. I’m a glutton for punishment, anyway.