Appetites: A look at America's processed food

In the book, "Pandora's Lunchbox: How Processed Food Took Over the American Meal," New York Times writer Melanie Warner takes a look at American food, and its ties to obesity, diabetes, and a host of other health problems.

Warner will be interviewed by Dara Moskowitz Grumdahl, who writes about food for Minneapolis St. Paul Magazine, at MPR News' Top Coast Festival this Saturday.

Moskowitz Grumdahl joined MPR News' Tom Crann to preview the conversation.

• Find out more about the Top Coast Festival

An excerpt from "Pandora's Lunchbox":

A NUMBER OF YEARS AGO, I went to the supermarket and bought an overflowing armful of cereal boxes and cookie packages. I'd started writing about the food industry for the New York Times not long before, and I'd decided to test whether those expiration dates printed on packages actually meant anything. I'd always wondered what happened to food after the expiration dates passed. Would the cookies turn green or taste like old shoes? Would bugs crawl out of the cereal? I tucked the boxes and crinkly bags away in my kitchen for nearly a year. The dates printed on the packages came and went, and when I opened them, the results were fairly unremarkable: my cereal and cookies looked and tasted perfectly normal, almost as if I'd just bought them.

I started wondering how long other foods would last. My experiment expanded--frozen dinners, kids' lunches, loaves of bread, processed cheese, hot dogs, pudding, and Pop-Tarts. I brought home samples of fast-food burgers, fries, chicken sandwiches, and chicken nuggets. At the time I was working from home, and I had to keep everything out of reach of our two young sons, who were never able to understand why they couldn't eat just one Oreo or have a taste of a Pop-Tart.

I worried that my work area might succumb to some sort of awful infestation. I pictured fruit flies or those tiny worms that get into the forgotten bag of flour in the back corner of the top cabinet. But none of this happened. Much of my collected food stubbornly refused to decay, even after as many as six years--far beyond expiration dates.

I wondered what had happened to this food to make it so eternal, so unappealing to the mold and bacteria that normally feast on ignored leftovers and baked goods. It seemed to me that the dates printed on the package had little to do with true "expiration." What did those dates actually mean? How was it possible that foods that seemed perfectly edible could be immune to natural processes of decomposition? What were we actually feeding our kids?

Around our house, my experiments were regarded as little more than mildly amusing, sort of weird, and definitely gross. My food collection was a funny little hobby. Until the guacamole incident.

On a Fourth of July trip out of town in 2011, my husband had returned from the grocery store with a tub of "fresh guacamole." "They made an announcement over the loudspeaker that they had just made it over at the deli, so I went and got some," he said proudly.

The container had a haphazardly applied sticker on it, indicating that it very well could have been "made fresh" by one of the store's white-coated deli workers. But there was something unusual about the ingredients: Hass avocados, salt, ascorbic acid, citric acid, xanthan gum, amigum, text-instant, tomatoes, yellow onion, jalapeno, cilantro.

I was knee-deep in research on food additives, but I'd never heard of amigum or text-instant. I went to the store and bought another tub, tucking it into our fridge at home and figuring I'd look into those strange ingredients later. Mostly I forgot about it. Then, nine months later, my mom, who lives with us in Boulder, Colorado, announced she'd tried some of the guacamole. We'd just had a birthday party for one of our boys, and I'd bought some dips from Whole Foods. I hoped that was what she was referring to, but I was pretty sure all of it was gone.

My mom had tried the other guacamole, the Fourth of July stuff, of course. "It was a little spicy," she declared.

My food museum was nauseating, but it had never occurred to me that it could actually sicken anyone. I was concerned because, as an older person, my mom has a higher risk of contracting a life-threatening food-borne illness. Mom assured me everything would be fine; she is nothing if not an unrelenting optimist. Amazingly, though, she was right. Not even an intestinal rumbling. She'd only tried a little, thank God.

Some people probably would have looked at that tub of green goop and not eaten any of it. It was brown around the edges and didn't look particularly fresh. But others might have done exactly what my mom did, and mistaken it for something edible. Even homemade guacamole tends to darken after a few days, and what my mom ate had none of the red flags that help guide us in our decisions about whether or not to consume something. There was no mold and no bad smell.

Like so much of the food we eat today, this immortal guacamole was not what it seemed. It had, in fact, been prepared--or assembled--by those deli workers, but not according to any recipe you'd use at home. It didn't look like a processed food, but that's exactly what it was. Along with the usual avocados, tomatoes, and onions, this guacamole had corn. Or corn manipulated beyond recognition so that it had been transformed into preservatives you can't taste, smell, or see. And then there was that "text-instant," as well as "amigum"--an ingredient that, I later learned, was even more bizarre than I could have imagined.

And that is the story of so much of our food, it turns out. Although my mother instilled in me a healthy skepticism of processed foods growing up, allowing me very limited access to what she called "gooped-up" food, I had no idea just how tremendously technical our food production had become until my food experiments impelled me to take a closer look. What started as an earnest attempt to understand the true meaning of labeling on the packages of the foods so many of us eat became a larger journey that brought me inside the curious, intricate world of food science and technology, a place where food isn't so much cooked as disassembled and reassembled. Over the last century, such complex modes of production have ushered in a new type of eating, what we call processed food.

Considering our vast and bewildering cornucopia of modern food choices, it's easy to forget that most of the items lining the inner aisles of the supermarket and the substances offered on fast-food menu boards simply didn't exist a century ago. The avalanche of prefabbed, precooked, often portable food into every corner of American society represents the most dramatic nutritional shift in human history. If we really are what we eat, then Americans are a different dietary species from what we were at the turn of the twentieth century. As a population, we ingest double the amount of added fats, half the fiber, 60 percent more added sugars, three and a half times more sodium, and infinitely greater quantities of corn and soybean ingredients than we did in 1909.

The trouble with this wholesale remaking of the American meal is that our human biology is ill equipped to handle it. The way our bodies metabolize food is stuck somewhere in the Stone Age, long before the age of Cheez Whiz, Frosted Flakes, and Classic Chick'N Crisp fried in vegetable oil. Our many novel and high-tech manipulations of food destroy much of its essential geography, resulting in all sorts of unintended consequences. When we start taking food apart and industrially processing it, it often stops making biological sense.

Processed food is even more ubiquitous than we think it is, in part because many products are designed to look as if they're not really processed at all. Subway's "fresh" sandwiches and the center aisles at Whole Foods, for instance, can both be quite perplexing. What are boxes of General Mills's Cascadian Farm's Fruitful O's and Cinnamon Crunch, if not Froot Loops and Cinnamon Toast Crunch by other names? Whole Foods co-founder John Mackey once acknowledged that some of what his stores sell is a "bunch of junk." And Subway's bread is not much more fresh and its meat no more whole than the bags of chips sitting up at the register. In total, some 70 percent of our calories come from this sort of (ultra) processed food. As an industry, this amounts to $850 million a year.

And yet many foods that some might call processed in fact are not. At one point during my research, I attended an industry conference where the keynote discussion sought to tackle the merits of food processing. The example most often cited was pasteurized milk. Thank goodness for food scientists, the argument went, who save Americans from countless outbreaks of campylobacter and E. coli. Yes, thank goodness, but pasteurized milk, let's be clear, is not a processed food. Nor are frozen peas, canned beans, washed and boxed spinach, bags of baby carrots, packages of aged cheese, or boxes of raw, frozen ground beef shaped into hamburgers.

At one point in time these products undoubtedly would have been heralded as newfangled creations. But today they barely register on the processing continuum and are not included in that 70 percent figure, which comes from a rigorous analysis done by the Brazilian nutrition scientist Carlos Monteiro. As a general rule--in a universe of tens of thousands of foods, there are always exceptions--a processed food is something that could not be made, with the same ingredients, in a home kitchen. Your home kitchen.

I've written this book with the core belief that it's important to understand what we're eating. Some people won't want to know and would rather just keep eating all their favorite foods in peace, and this book isn't for them. But for those who believe in the virtues of a health-promoting diet for themselves and their families, few things are more important to understand than what happens to our food before it gets to our plates--whether it's arrived from the farm reasonably intact or has had a long, multibranched journey through the nutritionally devastating food-processing industrial complex.

The aging guacamole notwithstanding, my mom, who read food labels with a discriminating eye long before it was fashionable, still does her best to avoid "gooped-up" food. She cooks most of what she eats and continues to survey ingredients (although apparently not if the food is already in the fridge). But her diet isn't one of deprivation. She eats meat and dairy and plenty of butter. She's never been lactose-free, sugar-free, caffeine-free, or fat-free. Nor does she have any plans to go gluten-free: the woman eats more bread than anyone. The only organizing principle of her diet is that she predominantly consumes things she would have recognized as food growing up in the thirties in Nova Scotia. She doesn't eat fast food; there was none back then. And she's never owned a microwave; they weren't available until the seventies.

It seems to have worked well for her. In her early eighties, she's in near-perfect health, with no chronic conditions and no prescriptions to fill, something that, if you ask her, she will attribute in no small part to what she eats. "What you put into your body matters, Melanie," she told me more than once while I was in college, eating Pop-Tarts and pizza for dinner. "Just because it's edible doesn't mean it's good for you."

As hard as it was to acknowledge at the time, she was on to something.

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