The danger of ultra-processed foods

Ultra-processed foods are the extreme end of the NOVA spectrum, a food classification system developed by Brazilian epidemiologist Carlos Monteiro that organises foods not by their nutritional composition but by the degree of industrial processing they have undergone. In group 4, the ultra-processed category, are products that combine industrial ingredients such as protein isolates, hydrogenated fats, modified starch, emulsifiers and flavour enhancers in proportions and forms that would not exist in a home kitchen.

The problem is not only caloric density or added sodium and sugar — factors that conventional labelling systems try to capture. Monteiro's hypothesis and the evidence accumulated over the last ten years point to something in the ultra-manufacturing process of these foods — beyond their individual nutrients — having health effects that classical nutritional analysis does not detect. The most robust follow-up studies, such as NutriNet-Santé in France with more than 100,000 participants, found associations between high consumption of ultra-processed foods and higher incidence of cancer, type 2 diabetes, cardiovascular disease and overall mortality, adjusted for factors such as social class, physical activity and other dietary components.

The practical challenge is that ultra-processed foods are cheap, convenient, palatable by design and available at any point of sale. In middle and lower-income countries they are often the most accessible option for families with limited time and resources. The public health policies that have shown some effect — such as mandatory octagonal warning labelling in Chile, Mexico and Peru — address the information dimension of the problem but not that of access and price, where the most difficult barriers reside.