Researchers compared two menus that reflect a typical Western diet: one emphasizing minimally processed foods and the other the extremely processed variety, according to the NOVA Food Classification System.
This system categorizes foods into one of four groups based on processing-related criteria. It was developed by the Center for Epidemiological Studies in Health and Nutrition of the School of Public Health of the University of Sao Paulo, Brazil.
The less processed menu was more than twice as expensive and reached its expiration date more than three times as quickly, without providing any additional nutritional value.
This finding showed that "both highly processed and less processed foods can have low healthfulness scores," Allen Levine, a professor emeritus in the Department of Food Science and Nutrition at the University of Minnesota in St. Paul, told UPI via email.
Levine classified the different foods in the NOVA system for the study.
"Ultra-processed foods with a healthy eating score similar to less processed foods also have a longer shelf life and are less expensive," Levine said.
Based on these findings, it may be possible to consume a low-quality diet even if you select primarily minimally processed foods, the researchers noted.
"The results of this study indicate that building a nutritious diet involves more than considering food processing as defined by NOVA," the study's lead researcher, Julie Hess, said in a press release.
"The concepts of 'ultra-processed' foods and 'less processed' foods need to be better characterized by the nutrition research community," says Hass, a nutritionist at the U.S. Department of Agriculture/Agriculture Research Service Grand Forks Human Nutrition Research Center.
Last year, the team published a study showing that you can create a high-quality menu that meets dietary guidelines while getting the most calories from foods classified as ultra-processed.
For the new study, the researchers asked the opposite question: Can you create a low-quality menu that gets the most calories from "simple" foods?
To answer that question, they created a less processed menu, which got 20% of its calories from ultra-processed foods, and a more processed menu, which got 67% of its calories from ultra-processed foods. The NOVA system determined the level of processing involved in each menu.
Researchers calculated that the menus had a score of 43 to 44 out of 100 on the Healthy Eating Index. This is a relatively low figure that indicates poor adherence to US dietary guidelines.
They estimated that the less edited menu would cost $34.87 per day per person, compared to $13.53 per day for the more edited menu. They also calculated that the median time to shelf life for the less processed menu items was 35 days, compared to 120 days for the more processed menu items.
The study shines a spotlight on the gap between food processing and nutritional value, the researchers said. Some nutrient-rich packaged foods can be classified as ultra-processed, such as unsweetened applesauce, ultra-filtered milk, liquid egg whites and some brands of canned raisins and tomatoes.
"When it comes to consuming an affordable healthy diet, both nutritional quality and price can come together," said registered dietitian Joan Salge Blake, clinical professor and director of nutrition programs at Boston University. She was not involved in the investigation.
Blake recommends using the grocery store's circular or app to find healthy foods (fresh, frozen, canned, or packaged) that are on sale and planning your weekly meals around these items.
"Use the nutrition facts chart on the label as a guide to assess the nutritional value of the foods you choose, rather than being afraid of the level of processing," she says.
However, according to Dr. Zhaoping Li, professor of medicine and director of the Center for Human Nutrition at the David Geffen School of Medicine at the University of California-Los Angeles, ultra-processed foods can significantly contribute to obesity and related chronic diseases if they are high in added sugars, unhealthy fats and artificial additives and have low nutritional value.
"Ultra-processed foods were initially developed to provide convenient and affordable sources of calories, aimed at preventing malnutrition," Li said, adding that they have become increasingly popular because they often appeal to consumers' taste preferences with ready-to-eat or ready-to-prepare food formats.
She recommends replacing processed foods with a variety of fresh and nutrient-rich foods whenever possible.
A diet consisting of whole grains, lean proteins, healthy fats, fruits and vegetables "ensures that the body gets the necessary vitamins, minerals and other beneficial substances," Li said.
"By prioritizing the quality of your diet you can prevent chronic diseases, improve your energy levels and support your overall well-being," she added.
According to Liz Weinandy, a registered dietitian and nurse practitioner at The Ohio State University Wexner Medical Center in Columbus, the research indicates that the health value of food involves more than just the amount of processing it undergoes before reaching the consumer.
"However, I don't think anyone would disagree that sugary drinks, candy and chips have low nutritional value and should not be consumed regularly," Weinandy said. "We don't want to put lipstick on a pig."
