Discover what ultra-processed foods are, how they impact your health, and tips on how to make the healthiest food choices in this nuanced, evidence-based guide to ultra-processed foods.
You’ve probably heard that “processed foods are bad” on social media and the Internet. And now there’s a new term called “ultra-processed foods” floating around, which sounds even scarier. But what do these terms really mean, and do they help you make better choices in the supermarket aisle?
You may consider processed or ultra-processed foods (UPFs) to include a long laundry list of low-nutrient foods you want to limit in your diet, such as candy, sugary sodas, cookies, and snack foods. Indeed, these foods do fall into the UPFs category of processing. But you might be surprised to learn that some “healthy” foods fall under the processed and UPF categories, too. Breakfast cereal, yogurt, canned beans, tofu, bread, and plant-based milk are but a few examples of nutritious foods that are technically UPFs.
That’s not to say that all processed foods in today’s markets support optimal health goals. Over the past couple of decades, health experts—including myself—have sounded the alarm on today’s intake of highly processed low-nutrient foods, raising concerns that such foods provide high levels of added sugars, sodium, saturated fats, and artificial ingredients, without the benefit of higher levels of nutrients, such as protein, fiber, vitamins, minerals, protein, and phytochemicals (plant compounds with antioxidant activity). That’s why the Nova classification was created, which classifies foods into four groups by their level of processing, with UPFs categorized as the highest level of processing (see below.)
Nova Food Processing Categories
Since the Nova was developed, scores of studies have been published on the health risks of eating high levels of UPFs. In a recent meta-analysis published in the BMJ, greater exposure to UPFs was linked with 32 different health associations, including mortality, cancer; and mental, respiratory, cardiovascular, gastrointestinal, and metabolic health outcomes (see below). Up to 60% of our calories in the U.S. come from UPFs, and 70% of the country’s food supply is considered UPFs, according to a recent study. It’s important to note that not all UPFs are created alike. Those that have the strongest association with health outcomes include ready-to-eat meat, poultry and seafood products, sugar sweetened and artificially sweetened drinks, dairy-based desserts, and ultra-processed breakfast foods.
The Nova Food Classification Framework
The Nova food classification system classifies foods into four groups by the level of processing:
Group 1 Unprocessed or Minimally Processed Foods:
These are naturally occurring foods with no added substances, such as salt, sugar, oils, or fats. These foods include milk, meat, fish, poultry, plain yogurt, fresh or dried beans, fresh, frozen, or dried fruits and vegetables, grains like oats, grits, and rice.
Group 2 Processed Culinary Ingredients:
This category includes food products from Group 1 or foods from nature that have been processed in some way through pressing, refining, grinding, milling, and drying. These are foods you would use at home or in restaurants to prepare foods in Group 1, including vegetable oils, butter, cream, vinegar, salt, sugar and molasses from cane or beet, honey, and maple syrup.
Group 3 Processed Foods:
These are food products made by adding sugar, oil, and/or salt to create foods from Group 1 by way of techniques like canning, pickling, smoking, curing, or fermentation. Group 3 foods include canned vegetables, fruits, beans, and fish; salted or sweetened nuts, smoked or cured meats without nitrates, freshly made bread, cheese, wine, beer, and cider.
Group 4 Ultra-Processed Foods:
This classification of foods are those industrially created with the addition of multiple ingredients that may include some from Group 2, as well as additives to enhance the taste or convenience of the food, such as hydrolyzed proteins, soy protein isolate, maltodextrin, high fructose corn syrup, stabilizers, flavor enhancers, non-sugar sweeteners, and processing aids, such as stabilizers and anti-bulking agents. In addition, they may be formulated through processes like extraction or modification. Group 4 foods include few intact Group 1 foods. Examples include commercially produced breads, rolls, cakes, cookies, donuts, breakfast cereals, snacks, soy burgers, flavored yogurts, ice cream, reconstituted meats, chicken nuggets, ready-to-heat meals like frozen pizza, canned soups, soft drinks, and candy.
Confusions over Processing Categories
One of the problems with the Nova categorization of foods is that it can be tough to determine where a food fits into these four categories. For example, fruit compotes with only sugar are considered Group 3 Processed, while flavored fruit desserts with added sugar are considered Group 4 Ultra-Processed. Here are a few additional clarifications of foods that would be considered ultra-processed, according to a recent study: Chocolate, margarines and spreads, breakfast cereals (even those without added sugars), nutrition bars, energy drinks, flavored milk drinks, cooked seasoned vegetables with ready-made sauces, powdered or fortified meal or protein substitutes, poultry and fish ‘nuggets’ and ‘sticks’, smoked or cured meats with added nitrates or preservatives (i.e., sausages, burgers, hot dogs, ham), and powdered and packaged instant products (i.e., soups, noodles and desserts.)
What Is Food Processing?
To set the story straight, food processing is not a 21st century invention—it’s literally been in place since prehistoric times, when our early human ancestors used basic techniques, such as cooking over the fire, salting, drying, smoking, and fermenting foods to make them taste better or last longer. Eventually we added home canning, refrigeration, and freezing to our arsenal of food preservation techniques. In the Industrial Revolution, our knowledge of food preservation was significantly advanced, with the advent of larger scale canning and pasteurization, which led to a more plentiful, safe food supply. This further evolved to today’s plethora of food products showcasing a range of food processing techniques, as well as additives.
A Nuanced Discussion on Processed Foods
Since the publication of the research on UPFs has come to light, a more nuanced conversation has emerged among nutrition professionals on how to offer eating advice on UPFs in a way that promotes a joyful, healthful diet for all people. While I have long recommended eating more minimally processed whole foods, such as beans, whole grains, fruits, vegetables, nuts, and seeds, people are often been confused as to how to spot “minimally processed” foods in the shopping aisle. For example, is a can of soup that lists vegetables and natural seasonings on the label considered “processed”? And now that health outcomes associated with the Nova classification have been published, it’s even more confusing to find foods we consider healthful—veggie burgers, soymilk, sliced whole wheat bread—falling into the UPFs category.
Sure, it’s easy to think that everyone should be eating more fresh fruits and vegetables and kernels of whole grains as part of a minimally processed diet, but many regions don’t have access to these foods year-round, not to mention the 13% of Americans who are food insecure and may only have access to foods that fall under the UPFs category. And what about precious cultural foods that are labeled as UPFs, such as tempeh, tofu, soymilk, and some tortillas? Let’s also consider that many foods on the UPFs list are nutritious, such as breakfast cereals, frozen dinners, soups, and plant yogurt. For example, a recent analysis found that popular frozen dinners were nutritionally comparable to homemade versions of those recipes, pointing out that food companies often start with whole minimally processed plant foods—pasta, grains, vegetables—as ingredients to create meals, just like we do at home. And after it’s all said and done, our diets don’t have to be so pure that we can’t enjoy a good old UPF now and again, such as a cookie, piece of chocolate, or a bowl of potato chips.
Here’s what I suggest: Use the Nova classification of processing as a guide. Spend more time evaluating foods on an individual basis as to whether they have value for nutrient intake, cultural preferences, and enjoyment.
