Markers of ultra-processing: Market analyses and association with mortality and morbidity

Abstract

Consumption of ultra-processed foods (UPF) is associated with a broad range of adverse health outcomes in epidemiological studies. A large number of these publications use the NOVA classification to define UPF. There are two kinds of ingredients that are exclusively found in UPF, i.e., non-culinary ingredients and cosmetic additives, which combined are referred to as markers of ultra-processing (MUP). Critics point out that the NOVA classification is too inconsistent and is based on broad and ambiguous definitions that are not supported by scientific evidence. Taking these studies into consideration, there are three main research gaps in the field of UPF that were analysed in the present work: (1) Which underlying mechanisms can explain the effects of UPF on overeating and body weight gain; (2) How can UPF be detected more objectively; (3) Can the MUP concept be adapted to the German food market? These research gaps have been addressed within three publications. In the first publication, added flavours were suggested to induce overeating and obesity by promoting hedonic eating and disrupting flavour-nutrient-learning. They increased feed intake and body weight as compared to non-flavoured control diets in a broad range of animal studies. In the second publication, UPF were detected objectively via a MUP- and ingredient listbased approach. Among all MUP, flavour was the most frequent marker for UPF detection. With a combination of three and six MUP, almost 80 % and 90 % of UPF were detected, respectively. In the third publication, the MUP- and ingredient list-based approach was transferred to the German food market. The proportion of UPF in plant-based meat products (PBMP) was higher than in meat-based products (MBP). Flavour and dextrose were the most frequent MUP in PBMP and MBP, respectively. Further research should focus on the following six steps: (1) Conducting further analyses of the worldwide food market concerning MUP; (2) Elucidating pathophysiological pathways by which the large number of other MUP apart from added flavours could lead to adverse health outcomes; (3) Analysing the association of the whole range of MUP with mortality and morbidity in epidemiological studies; (4) Studying the effectiveness of restricting selected MUP in randomised controlled or crossover trials; (5) Adapting the definition of UPF according to the findings of the previous steps; (6) Applying public health interventions to reduce UPF consumption and to change the food market towards more non-UPF.