Guests:

• Michael Pollan, food journalist and author of Cooked and The Omnivore's Dilemma
• Moises Velasquez-Manoff, author of An Epidemic of Absence

Ever heard the saying, "You are what you eat?" Authors Michael Pollan and Moises Velasquez-Manoff argue that our growing obsession with processed foods and living "germ-free" are radically changing the colonies of bacteria in our stomachs -- and, in the process, endangering our health.

The availability of processed foods has dramatically changed our lifestyles over the past few decades, both in the way we cook and in the way we eat. But it's also made a significant impact on another area of our bodies: our stomachs, and, more specifically, our stomach bacteria. Shockingly, bacteria in our bodies outnumbers our "actual" cells 10:1, making us really 90% bacteria and only 10% "human," and this bacteria plays an essential role in the body's digestion and absorption of energy from food. As our food has gotten further from its natural origin and become a lot more processed, our guts have suffered. Because processed foods contain little fiber, our gut bacteria is often unable (ironically) to process them, leading to inflammation.

"Inflammation" sounds like a pretty vague affliction, but can it have real consequences for our health? As it turns out, the answer is: yes, and in a lot of different ways. A recent study out of UCLA, for example, showed that women who ate yogurt with bacteria – which we often call probiotics – actually seemed to deal with stress better than those who didn't consume the bacteria. Another study suggested children who grew up on farms suffered from fewer allergies. Another study of ethnically similar groups of people living in Finland and right across the border in Russia found that those in the cleaner society of Finland tended to suffer more from a host of conditions. In short, the nature of your microbiome – the microbes living inside you – now look like they may influence many aspects of health from mental state to weight to allergies and auto-immune diseases.

So should you run out and replace everything in your pantry with sauerkraut, kimchi, and yogurt? The jury is still out. But, as Pollan notes, this smorgasbord of research points toward what actually seems to be a straightforward conclusion. "It's a really eloquent argument for something we've known for millions of years," he says, "which is: eat real food."

Still curious?

• "Some of My Best Friends Are Germs," by Michael Pollan via The New York Times.
• "A Roller Derby of Bacteria," by Veronique Greenwood via The New Yorker.
• "A Home for the Microbiome," via Science Daily.