The term “processed foods” has become a sweeping generalization for anything that comes in a bag or a box. Even my nutrition advice usually includes the general statement “eat less processed food and choose fresh food instead.” But that sentence simplifies a more complex story.
Of course, how we process food matters. Some ingredients can undergo changes — like being frozen, fermented or sprouted — that makes them as nutritious or more so than they once were. Not all processes are detrimental. Here’s how to tell the difference.
An apple is more nutritious than applesauce, and both are better choices than apple pie. The more processed a food is from its original state, the less healthy it becomes. To make it easier to discern just how processed a food is, researchers have developed categories for four distinct groups of foods. Take note of what goes in your grocery cart — and your body — based on these categories:
Group 1 — Unprocessed and minimally processed foods. This group includes basic whole foods such as vegetables, fruits, nuts, eggs, meat and milk. If processing is used, it’s to preserve shelf life, such as freezing vegetables and vacuum sealing meat. This group makes up about 30 percent of the calories we eat — but the percentage should be higher for these nutritious options.
Group 2 — Processed culinary ingredients. These foods enhance the flavor of meals and include olive oil, salt, honey and dried herbs. Some, such as olive oil, are more nutritious than others like sugar, but they only account for 3 percent of our calories when used in basic cooking, so they aren’t the main concern.
Group 3 — Processed foods. Foods that undergo some processing and contain just two or three ingredients fall into this group. Examples are canned fish, salted nuts and sourdough (fermented) bread. We get about 10 percent of calories from these foods. Many of these items are nutritious and make it more convenient to cook at home.
Group 4 — Ultra-processed foods. If you take processed foods (groups two and three) such as enriched flour, sugar and high fructose corn syrup, add food coloring, and put them into a Pop-Tart, you get an ultra-processed food. The foods in this group are the result of industrial formulations of five or more usually cheap ingredients. These foods provide almost 60 percent of our calories, but that percentage needs to be much lower. Collectively, ultra-processed foods are high in sugar, fat and salt, and they lack fiber, vitamins and minerals. People who consume more ultra-processed foods have a greater risk of obesity, hypertension and high blood sugar levels, which can lead to heart disease and diabetes. Other examples of ultra-processed foods are candy, instant soups, ice cream, breakfast cereals, soda and hot dogs.
Yogurt with added sugar is an example of a once-healthy food turned into less nutritious fare, as is powdered cheese on deep-fried potatoes. But not all processes are bad. When you do include some processed (not ultra-processed) foods in your grocery cart, consider the following:
Sprouted foods are nutritious. Whole grains and beans are living seeds, and a little “processing” with the right moisture level and temperature can make them sprout. Once they’ve sprouted, grains and beans are easier to digest, have minimal effect on blood-sugar levels, and contain more protein, fiber and B vitamins. Look for whole grains, beans and breads that say “sprouted” on the package.
Fermented foods contain probiotics. The recent focus on fermented foods such as yogurt and kimchee is based on the beneficial probiotics they provide. There is evidence that probiotics help support the immune system and relieve constipation and may have a role in preventing some types of cancer, and they are being studied for their role in managing cholesterol and treating neurological disorders. Want to get more probiotics in your diet? Buy yogurt, kefir (an effervescent milk beverage) and tempeh (fermented soy). Or try refrigerated sauerkraut or kimchee — but not the shelf-stable ones. They have been heated or pasteurized, which kills the probiotics.
Frozen foods retain more vitamins. If fresh vegetables have wilted in your crisper, use frozen options instead. They are blanched and quick-frozen, which isn’t detrimental to their nutrients. A comparison study of fresh versus frozen vegetables and fruit showed that vitamins C and E are the same or higher in frozen compared with fresh.