If you asked me to define "processed food" a few weeks ago, I would have invoked Supreme Court Justice Potter Stewart's response when asked to define hard-core pornography: "I know it when I see it." Moreover, I generally considered it something that "other people" consumed. (Not terribly unlike how I regard hard-core pornography, incidentally.)
It was therefore quite a wake-up call when I recently compiled the results of my family's weeklong food diaries for submission to the American Gut project. After documenting every bite that entered each one of our mouths for a week, I had to complete a questionnaire that required me to analyze the results. One question asked what percentage of our carbohydrate intakes came from "processed foods." The questionnaire then offered examples of what carbs the researchers considered to be processed. Among them: cereal, bread, pasta. Uh-oh.
Since then, I've been thinking a lot about what it means for a food to be "processed," and whether "processed" inherently means "unhealthy." Does lumping all processed foods into a single, vilified bucket risk throwing out the proverbial baby with the bathwater?
More often than not, the more processed a food, the less nutritious it is. But this is not always the case. The absorbability of lycopene (an antioxidant vitamin) is higher in cooked (canned) tomato products than from fresh ones, for example. Plain yogurt is a form of processed milk (in this case, by bacterial cultures) that retains milk's protein and calcium content while gaining probiotic benefits as a result of processing. Some processed foods - like canned pumpkin puree or frozen spinach - lose such negligible amounts of nutrients in processing that these convenient pantry items are virtually unimpeachable by the food police.
At the end of the day, all food exists on a spectrum of processing, from completely unprocessed, in which the food we eat is exactly how it existed in nature (eggs, bananas), to completely processed, in which nothing that goes into a product is in its natural state - if it ever even existed in nature to begin with (Twinkies, Cool Whip).
Most food we eat lies somewhere in between - from minimally processed (canned beans, baby carrots) to highly processed (energy bars, chicken nuggets). A diet that contains a few relatively more processed foods here and there can still support optimal health outcomes. But the more heavily weighted toward the processed side of the spectrum a diet is, the less healthy its eater is likely to be.
In assessing the nutritional quality of a diet, then, I've found it useful to think about which foods belong in which buckets of "processing," with the ultimate goal of moving myself, my family and my clients ever closer to the "minimalist" end of the spectrum.
-- Minimally processed foods: I consider these to be whole foods that have been trimmed, sliced or diced for convenience; par-cooked, cooked and/or mechanically altered to reduce cooking time; or cultured. They have no more than about two additional natural ingredients to help preserve freshness - like Vitamin C or a minute amount of added salt ( less than 5 percent of the daily value). Some examples include: canned beans, rolled oats, canned tomatoes (low-salt or no added salt) and peanut butter.
-- Moderately processed foods: These are foods whose raw ingredients have been transformed into something new and different. Think whole grains ground into flour to produce bread, pasta, cereal or fresh pizza dough; milk cultured or churned into yogurt, cheese or ice cream; cacao beans alchemized into chocolate bars; sweet potatoes peeled, seasoned and crinkle-cut into ready-to-bake fries; and meat trimmed and ground into burger patties.
The degree of processing varies widely for foods in this category, though by and large they are far more processed than they need to be. Compare the label of supermarket whole-wheat bread to a loaf of local bakery bread or a recipe for homemade bread, and you'll see what I mean. Ditto for reduced-calorie yogurts and desserts, protein- or fiber-enriched grain products and even treats like chocolate, ice cream or snack bars. What are all of those extra ingredients DOING in there?!?
Moderately processed foods can be perfectly healthy as daily staples - if chosen wisely. Within the categories of bread, cereal, yogurt, pasta, frozen foods and snacks like crackers, bars or popcorn, there are generally a few brands (or better yet, locally-made options) that produce versions with five ingredients or fewer. These are the ones that generally make my short list. If one of those ingredients is sugar, the best choice is the one with the least of it. Among grain-based foods in particular, products that use whole - rather than refined - grains are the best option. If you deem a food to require more sweetness, saltiness, fiber or protein - you're almost always better off buying a basic version and customizing it to your needs with an appropriate sweetener, condiment, spice, topping or side dish rather than opting for the fully-loaded industrial version.
-- Junk food: These are foods we'd do better eating less of. The category can be split into two sub-categories as follows:
a. Organic junk food: These are the boxed dinners, cookies, sweetened cereals, fruity yogurt drinks, chips and gummy snacks that lure you with claims like "100 percent natural" and labels featuring friendly farm animals. Make no mistake: Organic sugar is still sugar, and while it's admirable that growers aren't decimating our farmlands with pesticides to grow organic sugar beets for those organic lollipops, your waistline can't tell the difference one way or another. Organic junk food is likely to be as high in refined carbs, added sugar, fat and/or empty calories as its conventional counterpart.
b. Conventional junk food: Equally fattening and bad-habit-forming as organic junk food, conventional junk food has the dubious distinction of also including artificial colors, sweeteners, preservatives and flavors that are verboten for use in its organic counterparts. Beyond the same genre of cookies, snack cakes and chips that's available in organic junk, conventional junk offers feats of food engineering such as 90-calorie fiber bars, calorie-free whipped toppings and neon-colored soft drinks and cereals containing dyes that have been linked to attention deficit disorders in children. Interpreting ingredient labels requires an advanced degree in chemistry; indeed, an entire book has been written with the express purpose of decoding the Twinkie label.
As a working mom with two toddlers to feed and no yard in which to grow my own anything, processed food-containing meals like cereal for breakfast or peanut-butter sandwiches aren't going to be exiting my meal rotation anytime soon. And will I swear under oath that my own pantry has never harbored a bunny-shaped organic boxed macaroni product? I will not.
But so long as my daily menus remain weighted heavily toward the fresh fruits, veggies, beans, nuts and cooked whole grains, I forgive myself the occasional lapse into those inner aisles of the supermarket. At the end of the day, it's the total dietary pattern that matters far more than any individual food.
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Tamara Duker Freuman, MS, RD, CDN, is a NYC-based registered dietitian whose clinical practice specializes in digestive disorders, Celiac Disease, and food intolerances. Her personal blog, www.tamaraduker.com, focuses on healthy eating and gluten-free living.