Research Roundup
Ultra-Processed Foods and Childhood Obesity: Current Evidence and Perspectives
29 January 2025
This review (1) examines the relationship between the consumption of ultra-processed foods (UPFs) and the development of obesity in children and adolescents.
The NOVA food classification system categorises foods into four classes based on their level of processing. UPFs fall into the fourth class, characterised by extensive industrial processing and the addition of various additives such as sweeteners, flavours, preservatives, and emulsifiers.
Recent findings suggest that the widespread consumption of UPFs among children is associated with abnormal metabolic parameters. These include increased body mass index (BMI) and waist circumference (WC), as well as elevated levels of low-density lipoprotein cholesterol (LDL-C) and triglycerides, along with higher fasting plasma glucose and insulin resistance.
The review also explored the association between maternal consumption of UPFs during pregnancy and the risk of obesity in their children. This association is mediated by several mechanisms, including epigenetic changes, inflammatory responses, and the influence of maternal dietary habits on child-rearing. Cited studies indicated the following:
- The high content of sugars, saturated fats, and additives in UPFs may adversely affect foetal development and metabolism.
- Maternal diet can lead to epigenetic modifications in the foetus. For instance, low adherence to a healthy diet, such as the Mediterranean diet, is linked to increased methylation at specific genes involved in growth and energy balance.
- UPFs often contain additives and chemicals that can trigger inflammatory responses. Chronic low-grade inflammation during pregnancy may impact foetal development, potentially increasing the risk of obesity in offspring.
- Maternal dietary habits shape the dietary preferences of their children. Increased consumption of UPFs by mothers can lead to similar preferences in their children, heightening the risk of obesity.
The review discusses various factors contributing to the overconsumption of UPFs, including lower family socioeconomic status, lower parental educational levels, religious preferences, lower costs, wide availability, and extensive advertising of UPFs.
A concern highlighted by the authors is the lack of detailed labelling on UPFs, which do not clearly list every ingredient. The availability of UPFs, extensive advertising, and their long shelf lives significantly contribute to their widespread consumption. Additionally, the school environment plays a crucial role in childhood obesity, with higher consumption of UPFs in schools being linked to increased obesity rates among adolescents.
Preventive interventions suggested in the review include educational programs for parents and children, legislative and policy measures, support for families with low socioeconomic status, and community and school programs aimed at reducing UPF consumption and addressing the public health threat of childhood obesity.
However, the review has several limitations. Many studies included are cross-sectional, which limits the ability to establish causality. Additionally, much of the dietary data is self-reported, making it subject to recall bias and inaccuracies, which can affect the reliability of the associations found between UPF consumption and obesity. While the review discusses possible mechanisms linking UPF consumption to obesity, such as inflammation and epigenetic changes, more research is needed to fully understand these pathways and confirm their roles.
The review highlights the necessity for more detailed research on specific types of UPFs and their individual effects on obesity and metabolic health.
Reference
- Vallianou, N.G., Kounatidis, D., Tzivaki, I. et al. Ultra-Processed Foods and Childhood Obesity: Current evidence and perspectives. Curr Nutr Rep 14, 5 (2025).
https://doi.org/10.1007/s13668-024-00596-y
