Why Less Ultra-Processed Foods in Your Diet May Change Everything

A significant majority, ranging from 70% to 90%, of the products manufactured by global food corporations are ultra-processed foods (UPFs). Such products are extensively packaged, heavily branded, and characterized by a high degree of artificiality. They are manufactured by deconstructing foods into their component parts, modifying them, and recombining them with cosmetic additives. Typically made from low-quality, refined ingredients such as starches, sugars, oils, and/or protein isolates, UPFs require multiple colorants, texturizers, synthetic flavors, and bulking agents to enhance their sensory appeal from initially inferior ingredients to hyperpalatability. Thus, UPFs are concoctions that offer little in terms of nutrition or satiation and promote addictive consumption patterns that lead to overeating. 

While UPFs may have originally emerged in response to consumer demand for greater convenience, their underlying rationale has evolved toward profit maximization and cost reduction amid the consolidation of agrifood corporations. Engineered for market dominance through an emphasis on convenience and profitability, they are now mostly designed to dominate the market, displacing traditional foods. Through aggressive marketing and sustainability claims, UPFs drive consumer demand, reinforce corporate power, and marginalize smaller food producers. Socially, they undermine communal eating practices, leading to individualized consumption that can contribute to disconnection and excessive consumption. 

The widespread influence of UPFs raises significant concerns regarding public health, environmental sustainability, and socio-economic equity within the global food system. Moreover, multinational corporations frequently blur the distinction between UPFs and less processed, benign foods (e.g., yogurt), attempting to create confusion about their health implications. In contrast to UPFs, traditionally processed foods have been a net positive over centuries and millenia, as they allowed to preserve out-of-season nutrients and to increase the biosafety and nutritional value of various agricultural materials. 

Even if it is true that the classification of UPFs by the NOVA system is not always robust at the level of an individual food item, and that the occasional consumption of UPFs may be unproblematic, the case against UPFs needs to be evaluated at the level of dietary patterns. Western-style diets dominated by UPFs are demonstrably harmful and have been responsible for the rapid deterioration of health whenever and wherever they have been imposed upon traditional cultures in the past.

Annual per capita consumption of ultra-processed foods (UPFs) is estimated at 100 kg in Western Europe and 120 kg in North America and Australasia, with ultra-processed drinks accounting for an additional 180 kg and 120 kg, respectively. In France, two-thirds of conventional industrial foods and half of organic products are categorized as ultra-processed. In high-income countries, UPFs constitute 15-60% of total caloric intake for adults, while in Brazil (where the NOVA classification of UPFs has been designed), it is 13-21%. In the US, over 70% of packaged foods are ultra-processed, and these foods make up 70-80% of the diet for the top consumers in the US, UK, and Australia. Children in Anglosphere countries get 55-65% of their calories from UPFs, with US youth consuming 61-67% of their energy from these foods between 1999 and 2018. Even in France, UPFs account for 46% of children's diets, compared to 35% for adults.

The global landscape for ultra-processed foods is poised to deteriorate further, driven by aggressive marketing tactics and the pervasive influence of large multinational corporations on public policy and scientific research. These foods are disproportionately consumed by lower socioeconomic groups, intensifying nutritional disparities and contributing to metabolic disorders in their children. 

However, even higher-income populations remain susceptible, lured by narratives framing certain choices as more virtuous. This vulnerability is particularly evident in the promotion of plant-based "alternatives" (which are essentially ultra-processed mock foods) and Nutrient Profiling Systems (NPS, such as Nutri-Score). Such approaches usually neglect or minimize the risks of ultra-processing while exaggerating the purported flaws of traditional animal-derived foods. Ultimately, they favor big food companies by enabling product reformulations tailored to NPS algorithms, such as cutting specific nutrients or incorporating "healthy" modifications. However, these tweaks fail to enhance true nourishment value, as ultra-processed foods' adverse health effects stem from factors beyond mere nutrient composition, rendering such changes ineffective or even counterproductive. 

For instance, people on diets with fewer animal-sourced foods but more ultra-processed plant-based foods that are said to be of “high nutritional quality” (e.g., industrial whole-grain breads, pre-packaged soups, ready-to-eat pasta, and commercial salads) do not display a lower cardiovascular risk than people on diets higher in animal products with low ultra-processing. With higher intake of ultra-processed plant-based foods of “low nutritional quality” (e.g., sugary cereals, sodas from plant extracts, crisps, or confectionery) risk even increases.
 

Ultra-processed foods are a primary modifiable target for early prevention of non-communicable diseases, including colorectal cancer, and diets high in UPFs are associated with higher risks of mortality, mental disorders, obesity, and type-2 diabetes. Intervention trials show UPFs consumption cause higher energy intake and weight gain compared to unprocessed diets. A variety of interacting mechanisms has been identified to explain these effects, including the dysregulation of endocrine responses, satiety signals, and immunity and liver functions, as well as adverse impacts on the gut microbiota. All of this is compounded by the nutrient-poor profiles of UPFs, which typically rely on cheap, refined ingredients like starches, sugars, and oils, while also leading to a chronic excess of fructose. The latter acts as a ‘signal of metabolic plenty’, driving fat accumulation and features of the metabolic syndrome.

During processing, the materials used are stripped of fibre and micronutrients, while acellular nutrients are generated due to the degradation of the food matrix. When such free nutrients accumulate beyond what is normally slowly released during digestion, they wreak havoc on the natural responses of both the human body and gut microbiota, which have been fine-tuned during evolution to accommodate wholesome foods. 

In addition, the combined use of cosmetic additives (colorants, artificial flavours and sweeteners, emulsifiers, etc), the presence of xenobiotics (e.g., from packaging materials), and the generation of harmful chemicals during processing (e.g., acrylamide, oxidation products, advances glycated end products, etc), have raised concerns based on their demonstrated effects on humans and animals, triggering pro-inflammatory signalling in the gut and bodily metabolism. 

Finally, the fact that UPFs provide the body with misleading sensory information (artificial sweeteners, fruity flavours, fat and salt replacers, umami taste, …), which is uncoupled from true nutritional value (energy, protein content, vitamins, minerals, …), may disrupt the appestatic control over satiety mechanisms. In other words, ‘fake food’ may provide ‘fake information’ at the metabolic level, which makes it impossible for the body to gauge nutritional input and act accordingly. In the case of uncertainty, evolutionary logic suggests that the appestat would command overeating (rather than restriction), as to maximize the chance of nutrient coverage.