This study proposes using a scoring system to identify low, moderate, or high intake of UPF. The results indicate that lower UPF intake (low frequency of consumption) is associated with better diet quality in C&A. Additionally, high UPF intake is positively associated with unhealthy eating patterns but inversely associated with a healthy diet. The role of UPF in children’s diets extends beyond immediate health effects, 18–20 influencing long-term food preferences 18 and the development of healthy dietary patterns in the future. 20,21 In Mexico, an increase in UPF intake of approximately 5 percentage points was reported among C&A from 2006 22 to 2016, 23 reflecting growths in the food industry and a radical transformation in the Mexican diet. 24,25
Although the complications associated with high UPF intake, such as obesity and chronic diseases, 26,27 are well known, it is essential to explore how these foods affect the intake of healthy nutrients. However, no specific amount of UPF that can be considered safe for the pediatric population has been determined. 28
Information regarding UPF and various outcomes has gained significant relevance recently, from observational studies to systematic reviews of clinical trials. 29,30 Despite the available information, conducting meta-analyses has been challenging due to data heterogeneity. A recent systematic review mentioned that nutritional interventions aimed at eliminating UPF intake reported no changes in intake. 30 This heterogeneity limits the extrapolation and comparison of results, as well as short- or medium-term goals for its intake.
Several studies and health organizations, such as the World Health Organization, 31 emphasize the importance of limiting UPF intake to improve diet quality and prevent chronic diseases, 32,33 as a crucial early intervention, especially given the negative impact of UPF. 31–35
Energy and macronutrient requirements for C&A are significantly lower than those for adults and should be adjusted according to their stages of growth and development. 36,37 However, caloric intake in the high UPF intake group resembles that of a high school teenager, despite the study population having a median age of 11 years. This suggests that energy intake observed in C&A, especially in the moderate and high UPF intake groups, exceeds the expected energy requirements for their age group, 38 which could have negative implications regarding unhealthy daily dietary habits. 33,39–42
Significant associations between different intake patterns and UPF scores were identified through principal component analysis. For instance, component 2, characterized by lower sugar and fat intake and higher legume intake, acts as a protective factor against high UPF intake. In contrast, component 4, which includes fruits, dairy, and sugar, represents a risk factor. An example of a meal that may appear healthy but includes UPF is chocolate milk with added sugar accompanied by an apple, illustrating how certain healthy foods are paired with high UPF intake due to a lack of awareness of UPF content. Evidence supports the use of principal components for analyzing other diets, enabling the development of indices tailored to specific populations and dietary contexts. 43,44
Identifying protective and risk factors associated with UPF intake through dietary patterns provides a basis for future longitudinal research to establish temporal trends and population-specific parameters for more precise guidelines on acceptable UPF intake, contributing to child health.
Our findings reveal that a higher UPF score is associated with lower fiber intake and higher intake of fats and sugars. This pattern suggests that children consuming more UPF tend to have lower nutritional quality diets. 12,45–47 Specifically, participants with “high intake” of UPF (8–10 points) showed significantly higher energy and saturated fat intake and lower fiber intake compared to those with “low intake” (3–5 points).
Our results also showed that even within moderate ranges of UPF intake, similar effects were observed across other groups, impacting overall diet quality. 10,12,32
Our tool adapts and strengthens the NOVA system, which aids in understanding food quality and its health impact, for the pediatric population, considering the magnitude of UPF intake and classifying participants into low, moderate, and high intake tertiles. 14,48
Furthermore, this study underscores the importance of promoting healthy eating habits from an early age. Our results find UPF intake to be a global public health issue, primarily affecting vulnerable and low-income populations due to the low cost and high availability of these foods. 49–51
The strengths of the UPF score lie in its simplicity as a tool for assessing UPF intake in C&A, and of the main strength of using the UPF score is that being a three-day food record, it helps assess the frequency and quantity of UPF consumed; however, the main limitation is the nature of the study does not allow establishing causal associations, and the exact number of daily servings of UPF consumed was not identified.
The study’s findings underscore the importance of limiting UPF intake in children’s diets to promote better nutritional health. Accordingly, using the UPF score can guide nutritionists and healthcare professionals in clinically assessing and monitoring children.