A recent study of nearly 41,000 American adults shows that, on average, we get more than half our daily calories—a whopping 57 percent—from ultra-processed foods (UPFs). Hundreds of other studies show that UPFs aren’t doing our health any good. In fact, say many nutritional experts, a diet loaded with UPFs may be the No. 1 reason why so many of us are obese and suffer with chronic conditions like heart disease and diabetes.
Here is everything you need to know about UPFs—and easy ways to include more whole, minimally processed foods in your diet.
Many foods you eat are processed—the food is altered from its original form with heating, pasteurizing, drying, and other methods. UPFs take processing to the extreme. According to one widely accepted scientific definition, UPFs are “industrial formulations with five or more added ingredients.” Typically, the formulation contains little or no whole foods. (See sidebar.)
Examples of UPFs include fast foods, frozen pizzas, white bread, sodas, energy drinks, chips and other salty snacks, cookies and other sweets, and sweetened breakfast cereals. But the list is virtually endless: In a database of 50,000 foods sold in the United States, 73 percent were ultra-processed.
A food is ultra-processed if it has most or all of the following features:
Calorie-rich, nutrient-poor. UPFs are typically loaded with sugar, salt, saturated fat, and calories, but low in healthy nutrients. In a study of more than 9,000 people, published in Population Health Metrics, the more UPFs in the diet, the less protein, fiber, vitamins A, C, D, and E, calcium, magnesium, potassium, and zinc.
Artificial ingredients. The labels of UPFs read like a chemistry experiment, with listings of mostly unpronounceable names—the artificial colorings, artificial sweeteners, artificial flavorings, flavor enhancers, stabilizers, thickeners, emulsifiers, defoaming agents, preservatives, and other additives that constitute the product.
Addictive. UPFs are engineered by food scientists to create the “just right” amount of sweet, salty, and fatty tastes that keep you coming back for more. In fact, UPFs act on your brain exactly like cocaine, heroin, and other addictive drugs: They stimulate the pleasure circuits that make you desire the foods and want to buy and eat them again and again. Like any addictive substance, you crave them. You consume them even though you know they’re bad for you. But you also develop a tolerance for them and need larger and larger servings to create feelings of satisfaction. In addition, some common ingredients in UPFs—like the flavor enhancer monosodium glutamate—have neurological effects that create a drug-like “buzz.”
No real satisfaction. With their empty calories and stimulating components, UPFs never create a real sense of “satiety”—the sensation of feeling full that tells the appetite center in the brain it’s time to stop eating.
The addictive and unhealthy nature of UPFs was proven most conclusively in a study conducted by researchers at the National Institutes of Health and published in Cell Metabolism in 2019. For the study, 20 people lived in a closed hospital ward for 30 days. For two weeks, they ate as much (or as little) as they wanted of UPFs. For the next two weeks, they ate as much (or as little) as they wanted of an unprocessed, whole foods diet. The people eating the ultra-processed diet ate, on average, 500 more calories a day than they did while eating unprocessed food. And they gained 2 pounds. In contrast, the study participants lost 2 pounds while eating whole, minimally processed foods.
Research shows that a diet loaded with ultra-processed foods is an unhealthy diet.
High blood pressure. A study in Public Health Nutrition in 2021 showed that a high intake of UPFs raises the risk of developing high blood pressure by 23 percent.
Poor heart health. Researchers from the U.S. Centers for Disease Control and Prevention found that people who got 70 percent of their calories from UPFs were half as likely to have “ideal” cardiovascular health compared with people who ate 40 percent or less of their calories from UPFs.
Obesity. In a meta-analysis of 12 studies published in Critical Reviews in Food Science and Nutrition in 2021, researchers found that a high intake of UPFs increased the risk of developing obesity by 55 percent.
Type 2 diabetes. In a study involving more than 1 million people and published in 2022 in the International Journal of Epidemiology, people who had a high intake of UPFs had a 31 percent higher risk of developing type 2 diabetes. Moderate intake increased the risk by 12 percent.
Higher risk of cancer. Eating more UPFs increases the risk of 13 of the 15 most prevalent cancers, according to a scientific paper in Obesity Reviews. For example, in a 2022 study from researchers at Tufts University and Harvard University, men who consumed the highest amounts of UPFs were 29 percent more likely to develop colorectal cancer compared with men who consumed the lowest rates.
Poor mental health. People who consume the most UPFs have more “mentally unhealthy days,” and more days on which they are mildly depressed or anxious, according to a study of more than 10,000 adults from researchers at Florida Atlantic University. And in a study of 152 adults, e-published in the Journal of Affective Disorders in May 2023, those with the highest UPF intake had a higher risk of depressive symptoms.
Dementia. In a 10-year study of nearly 11,000 people published in JAMA Neurology in 2022, people who ate 20 percent or more of their calories from UPFs had a 28 percent faster rate of cognitive decline. But if a study participant also ate a lot of whole foods—like green leafy vegetables, legumes (beans, peas, lentils), whole grains, nuts, berries, fish, chicken, and olive oil—the link between UPFs and cognitive decline disappeared.
There are many easy ways to eat more unprocessed or minimally processed foods.
Volumetrics. A cornerstone of eating more whole foods and fewer UPFs is to use the principle of volumetrics from food scientist Barbara Rolls, PhD, at Penn State University: Focus on foods that are low in caloric density, high in nutritional density, and have a lot of volume, so you feel fuller, faster. They activate real satiety, boost mood, and turn off the chronic low-grade inflammation that underlies chronic disease.
To get a better sense of the difference between UPFs and these “volumetric” whole foods, look at these two 100-calorie snacks: 10 jellybeans and 2¾ cups of strawberries. Both deliver the same number of calories. But 100 calories of jellybeans is a tiny portion, while 100 calories of strawberries is practically a meal.
Volumetric foods include:
Try a meal delivery service. If you want to learn how to make whole foods at home, try using a meal delivery service, like Hello Fresh or Home Chef. These services deliver a meal to your door, with a recipe card that shows you all the steps to cook it. Using the service is a little bit like going to cooking school: Over time, you get the experience of preparing meals that are as delicious as those served at nice restaurants and become confident in your own ability to assemble the right ingredients and cook scrumptious foods from scratch.
Prepare whole foods in advance. To reduce time-consuming daily preparation of whole foods, prepare filling foods at the beginning of a week, freeze them in individual portions, and reheat as needed.
Choose non-UPF beverages. Drink water and other low-calorie beverages. Stay away from sugar-sweetened drinks.
Just say no to long ingredient lists. Stay away from foods that have more than five chemical ingredients on the label.
Snack on whole foods. Rather than eating bag of ultra-processed chips, snack on carrot and celery sticks, with a delicious bean dip or homemade salad dressing.
The Nova Classification System describes four levels of processed foods:
