Food label debate: Spotlight on processing levels and nutrients in ultra-processed foods

20 Feb 2024 --- Research links diets high in ultra-processed foods (UPFs) to various health concerns, but experts are unclear whether this results from their processing level or high sugar, salt, calories and fat content. Scientists question whether adding processing levels to food labels can address consumer confusion about UPFs and their impact on health, as a new study supports that UPFs have unhealthier food labeling scores.

“Consumer skepticism about high levels of processing can aid consumers in selecting healthy food. But it can also prevent consumers from making sustainable choices. This is a dilemma the food sector needs to work with,” Klaus Grunert, professor at Aarhus University, Denmark, and director of the European Institute of Innovation and Technology (EIT) Food Consumer Observatory, tells Nutrition Insight. 

“EIT Food’s Consumer Observatory is calling for the latest science to match consumer messages. There is a need to disentangle levels of processing and healthiness and create transparency on both.”

He emphasizes that the most significant change needed is clarity, as food scientists, manufacturers and authorities cannot come to a “consensus on what constitutes UPFs and on how high degrees of processing are related to healthiness.”

Food label scores 
At the same time, researchers at the University College London (UCL) compared the UK’s front-of-pack “traffic light labeling” with NOVA classification that groups foods into different levels of processing. The study reveals that UPFs had unhealthier labeling scores with higher energy, fat, saturated fat, sugar and salt levels than minimally processed foods.

One step below UPFs on the NOVA scale, processed foods were unhealthy according to their product labels, though they were not as high in energy or sugar as UPFs. 

However, experts question the focus on processing levels to determine whether foods are healthy. They warn that the data used in the study does not capture all the details required by NOVA and does not show the contribution of foods to essential nutrients such as protein, calcium, iron, vitamins and fiber. 

Gunter Kuhnle, professor of nutrition and food science at the University of Reading, underscores: “There is currently no evidence that suggests that processing harms health beyond food composition and possibly texture, as the latter can affect eating rate and result in over-consumption.” 

“Shifting the focus of public health messaging from a well-understood system of food composition to a rather ambiguous system of processing is likely to result in confusion but not a better diet.” 

What’s healthy? 
The EIT Food Consumer Observatory highlights that consumers are confused and uncertain about what constitutes UPFs and how it affects health. A survey of almost 10,000 European consumers found that 65% believe UPFs will cause health issues later in life. 

“Consumers have learned about the importance of healthy eating, but they have relatively little knowledge about food processing,” underscores Grunert. “At the same time, European consumers are strongly preoccupied with naturalness, which they equate with better food. These factors together lead to uncertainty about the role of processing in healthy eating.” 

It is unclear whether UPF health risks are due to their processing level or high sugar, salt, calories and fat content.He adds that consumers are becoming increasingly skeptical about their foods due to this lack of clarity and widespread confusion. 

“Consumers are also hearing conflicting information from different sources; foods that they may have considered healthy in the past, such as fruit yogurts, are now being labeled as unhealthy and ultra-processed. However, the labels on these products may still convey a health message.” 

Traffic lights 
To determine the alignment of the NOVA scale with advice on front-of-pack labeling, UCL researchers examined data from the UK National Diet and Nutrition Survey, which tracks the diet of a sample of the population. The results are published in The British Journal of Nutrition. 

UK food labels inform consumers about a product’s nutrient content but do not consider food processing. As the country’s government is considering action on UPFs, it is unclear whether processing status should be added to these labels. In the current “traffic light” system, red means food containing high levels of energy, (saturated) fat, sugar and salt, amber means medium and green signifies low levels. 

“There is a clear overlap between the healthiness of food, front-of-pack labeling, and the level of food processing. This has implications for understanding what we eat and drink in the UK,” says Samuel Dicken, first author of the study from the UCL division of medicine. 

“What is clear from the types of food and drinks captured by red ‘traffic lights’ on front-of-pack labels and wide availability of UPFs is the need to change the food environment to support individuals in consuming a healthy, balanced diet. A focus on updating package labeling creates a complicated message and keeps the burden on the individual.”

Dr. Nerys Astbury, senior fellow in diet and obesity at the University of Oxford, cautions against adding more labels on food. “More labels on the front-of-pack could result in information overload (organic, red tractor, traffic light, nutrition claims etc), and conflicting messages.”

“The findings presented here suggest that the current traffic light system, while not perfect, captures food processing by and large and overlaps with the processing categorization of food using the NOVA system.”

Experts caution that adding more labels on the front-of-pack could result in information overload and conflicting messages.Nutrients or processing?  
Astbury highlights that a recent report by The Scientific Advisory Committee on Nutrition suggested insufficient evidence to “warrant inclusion of food processing into dietary guidelines, given that it is likely ultra-processing is already covered by existing dietary recommendations.” 

Although several studies link diets high in UPFs to higher risks for obesity, type 2 diabetes, cardiovascular disease and depression, she underscores that it is not clear from these studies whether these effects are a result of the processing or if it is because of the nutrient profiles of foods that tend to be ultra-processed, such as ready meals, crisps, cookies and chocolate. 

“Consuming a diet containing many UPFs can indicate other unhealthy dietary patterns and lifestyle behaviors. That’s because diets containing lots of UPFs also tend to have higher energy density — the energy (calories) in a given weight or volume of a food. The higher the energy density, the more calories per gram or ml in the food.” 

“They also tend to be higher in saturated fat, salt and sugar, higher in processed meat and low in fruits and vegetables and fiber, and all of these patterns have already been shown to be associated with adverse health outcomes.”

The UCL is currently working on a trial to assess if eating healthily on a UPF-only diet is possible compared to a minimally-processed food diet and whether guiding healthy eating can change people’s eating choices. The first results are expected in early 2025.

By Jolanda van Hal