What Does ‘Processed Food’ Even Mean, and Why Is It So Bad?

It shouldn’t be confusing, but it is. A nutrition expert explains what processed food is, what kind should be avoided, and how it impacts your health.

Photo: Jacobs Stock Photography Ltd/Getty Images

“L“Limit or avoid processed foods” has become a familiar nutrition mantra over the last decade. On the surface, it sounds fairly straightforward: Go easy on the double-stuffed cookies and neon orange chips.

But walk through any grocery store and it’s easy to get confused. Is bread — even the healthy whole grain sprouted kind — processed? How about canned beans? And what about that “paleo-friendly” protein bar with “natural” on its packaging?

The world of processed food is simultaneously simple and complex. I’ll break it down for you.

What are processed foods, exactly?

The United States Department of Agriculture (USDA) provides a legal and technical definition of a processed food: “any raw agricultural commodity that has been subject to washing, cleaning, milling, cutting, chopping, heating, pasteurizing, blanching, cooking, canning, freezing, drying, dehydrating, mixing, packaging or other procedures that alter the food from its natural state. This may include the addition of other ingredients to the food, such as preservatives, flavors, nutrients, and other food additives or substances approved for use in food products, such as salt, sugars, and fats.”

By that definition, a rinsed carrot, a chopped apple, and roasted broccoli are all processed foods.

So, is pretty much everything processed food? Nutritionally, the answer is a resounding “no.”

When nutrition experts like myself talk about processed foods, we refer to foods that have been processed to such a degree that there’s been significant nutrient loss and/or a significant addition of unhealthy ingredients (mainly in the form of added sugars, oils, or salt).

Food processing, therefore, exists on a continuum — think of a chopped apple as on the innocuous end and a candy bar on the “ultra fake” end.

To help clarify this confusion, the NOVA food classification system, developed by an international panel of scientists and public health leaders, helps to differentiate minimally processed foods that are not harmful to health from highly processed (also called “ultra-processed”) foods that have a detrimental effect on human health.

NOVA divides foods into four groups, based on the amount of processing they have undergone:

Group 1: Unprocessed, or minimally processed, foods

Defined as: “edible parts of plants (seeds, fruits, leaves, stems, roots) or of animals (muscle, offal, eggs, milk), and also fungi, algae, and water, after separation from nature.”

Group 2: Processed culinary ingredients

Defined as: “oils, butter, sugar, and salt, are substances derived from Group 1 foods or from nature by processes that include pressing, refining, grinding, milling, and drying.”

Group 3: Processed foods

Defined as: “Processed foods, such as bottled vegetables, canned fish, fruits in syrup, cheeses, and freshly made breads, are made essentially by adding salt, oil, sugar, or other substances from Group 2 to Group 1 foods.”

Group 4: Ultra-processed foods

Defined as: “Ultra-processed foods, such as soft drinks, sweet or savory packaged snacks, reconstituted meat products, and pre-prepared frozen dishes, are not modified foods but formulations made mostly or entirely from substances derived from foods and additives, with little if any intact Group 1 food.”

NOVA goes on to state: “The overall purpose of ultra-processing is to create branded, convenient (durable, ready to consume), attractive (hyper-palatable), and highly profitable (low-cost ingredients) food products designed to displace all other food groups. Ultra-processed food products are usually packaged attractively and marketed intensively.”

Why should you avoid them?

Definitions are one thing. But why has the topic of highly processed foods come up? Studies show that diets high in ultra-processed foods are harmful for people’s health.

Recent studies have concluded that higher consumption of ultra-processed foods is associated with:

This isn’t terribly surprising when we consider what ultra-processed foods offer — and what they don’t.

Ultra-processed foods are commonly high in added salt and sugar. High-sodium diets have repeatedly and consistently been linked with increased risk of stroke and total cardiovascular disease. The science demonstrating the harmful effects of added sugar is also prevalent, so much so that, in 2016, the U.S. Food and Drug Administration (FDA) mandated that added sugar — along with a percentage of the daily value recommended as a limit — be added to the nutrition facts panel in the United States.

Perhaps even more important, ultra-processed foods are stripped of a significant amount of the health-promoting components (fiber, phytonutrients, vitamins, and minerals) found in the original whole food. The loss of these nutrients can take a toll on overall health. Dietary fiber, for example, confers a variety of health benefits, including lowering blood pressure and heart disease risk as well as lowering incidences of colon cancer.

The negative health impacts of eating a diet high in ultra-processed food is clear. Yet approximately 60% of the daily calories consumed by the average American are from ultra-processed foods.

Considering the health implications of this dietary pattern, it is prudent that public health and nutrition organizations recommend avoiding or severely limiting these types of foods. But the U.S. food system also needs to make it easier for people to access affordable and fresh food.

The bottom line is food shopping shouldn’t be confusing, and how to eat healthy should be clear. Go for whole and minimally processed foods as often as possible; when in doubt, use nutrition labels and ingredient lists as guides.

Dietitian with whole-food, plant-centric approach. No, you don't need a juice cleanse.

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