Introduction
The increasing prevalence of ultra-processed foods (UPFs) in modern diets has raised concerns about their potential impact on public health. As these foods dominate supermarket shelves and are increasingly consumed due to convenience, affordability, and taste, questions about their long-term health effects remain crucial. Despite their widespread availability, the scientific understanding of UPFs and their direct correlation with health issues is still evolving. A recent expert appraisal conducted by the French Agency for Food, Environmental and Occupational Health & Safety (ANSES) explores the potential health risks posed by UPFs based on existing scientific literature. The findings of this report highlight possible mechanisms through which these foods might contribute to chronic diseases and emphasise the need for further research to develop effective public health interventions.
ANSES’s Scientific Opinion on Ultra-Processed Foods
On 30 January, ANSES published a scientific opinion on the health impacts of consuming ultra-processed foods. The agency concluded that ultra-processing is a concept that has yet to be scientifically substantiated. However, based on the available literature, ANSES identifies signals suggesting a link between the consumption of such foods and a higher risk of developing chronic diseases.
The ANSES report addresses the following key topics:
- Identification of processing methods likely to induce changes in the composition of foods that pose a health hazard.
- Inventory of existing classifications of foods according to their degree of processing and assessment of their relevance in light of the characteristics identified previously.
- Study of the epidemiological link between the consumption of UPFs and the risk of chronic non-communicable diseases.
ANSES’s Critique of the Nova Classification
The French Food Safety Authority (ANSES) published its Scientific Opinion related to the characterisation and assessment of health impacts of consuming ultra-processed foods (UPFs), concluding:
“The limitations of the Nova classification lead ANSES to consider that this classification cannot serve directly as a basis for the construction of tools for the prevention of non-communicable chronic diseases such as recommendations or inclusion in a categorisation mechanism. Regarding the “criterion of the purpose of the processes and the formulation”, the report notes that the objective of product preservation is found in all NOVA classes. However, this objective is expressed differently (“to allow their storage for longer use” for foods in class Nova 1, “long shelf life” for foods in class Nova 4). “This criterion is also imprecise, sometimes contradictory with the other criteria and therefore not consistent with the examples (UHT milk classified Nova 1 and canned foods classified Nova 3 have longer shelf lives than some products classified Nova 4 such as flavoured yoghurts). Thus, this criterion does not allow products to be discriminated and leads to confusion.”
ANSES considers that the results of the literature review, even if their weight of evidence is low, should be considered as a reason to explore avenues associated with the concept of ultra-processing, which are currently not taken into account in public health actions and which deserve investigation, such as high-energy foods, formulations that encourage large portion sizes, and consumption conditions (as in fast food settings).
- ANSES adds its voice to other public health authorities, such as the UK Scientific Advisory Committee on Nutrition and the Nordic Nutrition Guidelines, in criticising UPF classification schemes for being too imprecise and broad, leading to oversimplified conclusions.
Potential Mechanisms Behind the Health Risks
To explain the potential link between the consumption of UPFs and adverse health effects, ANSES formulates the following hypotheses:
- Food Formulation and Consumption Context: UPFs are designed to be appetising and convenient, often containing high levels of sugars, fats, and salts. These formulations promote excessive food intake, which, when combined with unhealthy eating contexts (e.g., eating quickly, while distracted, or in large portions), can lead to an imbalance in energy intake and weight gain.
- Formation of Harmful Substances During Processing: The methods used to process foods, such as frying, baking, or extrusion, can lead to the formation of novel substances, called neoformed substances, that may be harmful to health. Some of these substances are potentially toxic and may cause interactions within the body, increasing the risk of disease.
- Additives and Substances: The additives found in UPFs, such as artificial colourings, preservatives, and emulsifiers, might also have biological effects that alter gut health, inflammation levels, or metabolic processes. Some of these substances have been shown to disrupt the microbiome or interact with metabolic pathways in ways that could contribute to disease development.
To solidify these hypotheses, ANSES stresses the need for further studies that explore the specific ways in which food processing and ingredient formulation influence health outcomes. Longitudinal studies that track diet and health outcomes over extended periods will be particularly important for establishing causality.
Strategies for Improving Public Health
Given the rising rates of overweight and obesity in France, along with an increasing prevalence of physical inactivity and poor dietary habits, ANSES underscores the urgency of addressing the health risks of ultra-processed foods. The latest Esteban health study published by Santé publique France (2024) highlights a concerning trend: both obesity and sedentary behavior continue to rise, and dietary intake is still far from meeting recommended guidelines. The possibility that UPFs contribute to this growing public health crisis warrants further scrutiny.
However, ANSES emphasizes that current classifications of food processing, such as the Nova system, are not suitable for direct public health action or nutritional education. The report suggests that these classifications should not be used as the sole basis for dietary recommendations or consumer behavior campaigns. Instead, a more comprehensive approach that addresses overall dietary patterns, physical activity levels, and other lifestyle factors is needed to improve population health.
Moreover, ANSES calls for the evaluation of existing public health initiatives aimed at promoting healthier diets and increasing physical activity. These efforts should be continually assessed for their effectiveness in achieving the recommended dietary guidelines and improving public health outcomes.
Conclusion
ANSES’s latest report provides valuable insights into the potential health risks posed by ultra-processed foods, acknowledging the complexity of the issue. While evidence linking UPFs to chronic diseases is still emerging, the Agency’s review highlights several important mechanisms that may explain this relationship. Moving forward, more research is needed to clarify these mechanisms and to develop effective public health policies. The focus should not solely be on the classification of foods but rather on a holistic approach to improving nutrition and lifestyle behaviors across populations. Given the growing burden of chronic diseases, a deeper understanding of how food processing affects human health is critical to shaping future dietary guidelines and interventions.
Read more
https://www.anses.fr/en/content/better-understanding-potential-health-effects-ultra-processed-foods
