In a blog post a few years ago I wrote, 
with misplaced parenthetical self-assuredness:
Anybody who’s ever picked up an M&M off the sidewalk and popped it into his or her mouth (and, really, who among us hasn’t?) will be gratified to learn that the more germs you’re exposed to, the less likely you are to get asthma ... hay fever and eczema.
I soon learned to my surprise, if not necessarily to my embarrassment, that virtually nobody - at least nobody over 6 - cops to having stooped-and-scooped as I routinely did as a kid on what I called my "lucky-sidewalk" days.
But those M&Ms may have been the best pills I ever took.
Stanford microbiologists Justin Sonnenburg, PhD, and Erica Sonnenburg, PhD, (they're married) have written a new book, The Good Gut, about the importance of restocking our germ-depleted lower intestines.
Massive improvements in public sanitation and personal hygiene, the discovery of antibiotics and the advent of sedentary lifestyles have taken a toll on the number and diversity of microbes that wind up inhabiting our gut. According to The Good Gut, we need more, and more varieties, of them. And we need to treat them better. The dearth of friendly microorganisms in the contemporary colon is due not just to a lack of bug intake but to a lack of fiber in the modern Western diet. Indigestible to us, roughage is the food microbes feast on.
The Good Gut packages that message for non-scientists. "We wanted to convey the exciting findings in our field to the general public," Justin Sonnenburg recently told me. "We'd noticed we were living our life differently due to our new understanding. We were eating differently and had modified both our own lifestyle and the way we were raising our children."
In simple language, the Sonnenburgs explain how the pieces of our intestinal ecosystem fit together, what can go wrong (obesity, cancer, autoimmunity, allergy, depression and more), and how we may be able to improve our health by modifying our inner microbial profiles. Their book includes everything from theories to recipes, along with some frank discussion of digestive processes and a slew of anecdotes capturing their family's knowledge-altered lifestyle.
These guys walk the talk. They make their own kefir. They talk about poop. The kids don't have to wash their hands before every meal.
This kind of candor is guaranteed to raise highbrows' eyebrows. The writer of a favorable review of the book in upmarket New York magazine, on visiting the scientists' home for an up-close-and-personal look at their daily routines, can't help but take a few smug "you won't believe this, but" swipes at the Sonnenburgs' earthiness.
Yet, readers will note, The Good Gut's authors - scientists that they are - take pains to explain not only what's known but what's not known about what's good for our guts: For example, practically all probiotics and prebiotics sold commercially have scant solid research behind them and are based on not much more than reasonable guesses about which friendly bacteria are likely to survive the trip through the human stomach and what, on arriving in the Promised Land below, they'll actually do there.
In my own simple words, here are three tips from The Good Gut:
- Eat tons of fiber. (Not at the outset, though. Work up to it.) Fermented foods, too, if they've got live cultures in them.
- If you're living in an urban, suburban, or exurban cleanroom, lighten up on the Lysol.
- Let your kids play in the dirt. Hell, let them eat it.
And in my own simple mind, I'm wondering just how many times those gritty, grubby M&Ms I pried off the pavement have saved my life.
Previously: Drugs for bugs: Industry seeks small molecules to target, tweak and tune up our gut microbes, Civilization and its dietary (dis)contents: Do modern diets starve our gut-microbial community?, Joyride: Brief post-antibiotic sugar spike gives pathogen a lift, Eat a germ, fight an allergy, The future of probiotics and Researchers manipulate microbes in gut
Jacket design by Rachel Willey
