Childhood obesity has emerged as a significant global public health issue, often leading to persistent health problems and metabolic disorders from a young age. While the impact of ultra-processed food (UPF) consumption on adult health is well-documented, there is a gap in understanding its effects on children’s metabolic outcomes. Given the rising trend in UPF consumption among children, it is crucial to examine its impact on key health indicators.
Study Overview
A recent prospective cohort study investigated the effects of UPF consumption on obesity and metabolic health among preschoolers in Chile over a two-year period. The study analyzed data from 962 participants in the Food and Environment Chilean Cohort (FECHIC) study. Researchers collected dietary information from four-year-olds using 24-hour dietary recalls, processed through the United States Department of Agriculture’s (USDA) multiple-pass technique.
To ensure accuracy, records with extreme UPF consumption were excluded, and mothers reported their children’s food intake during in-person interviews. Children also provided additional information about their eating habits outside their mothers’ presence, such as during school.
Food items were categorized using the NOVA classification system into four groups: natural and minimally processed foods, processed culinary ingredients, processed foods, and UPF. The study team used the Multiple Source Method (MSM) to estimate UPF consumption in terms of grams and calories.
Methods
At the follow-up in 2018, when participants were six years old, the researchers assessed various indicators of adiposity and metabolic health. Adiposity measures included waist circumference, fat mass percentage and kilograms, and body mass index (BMI) z-scores. Metabolic indicators included insulin levels, fasting blood glucose, insulin resistance (HOMA-IR), low-density lipoprotein cholesterol (LDL-c), high-density lipoprotein cholesterol (HDL-c), triglycerides, and total cholesterol.
The study estimated energy requirements using the Dietary Reference Intake (DRI) equation. Linear regression analyses, adjusted for covariates and total calorie intake, were used to explore the relationship between UPF intake and the study outcomes. The analysis accounted for potential loss to follow-up using inverse probability weighting. Covariates included age, sex, BMI z-scores, television time, and maternal factors such as BMI, age, education, employment status, and socioeconomic status.
Results
At the study’s start, participants had a mean age of five years, with 52% being female and a mean BMI z-score of 1.0. By the end of the study, average fat mass was 24%, and mean fasting glucose was 82 mg/dL. UPFs accounted for 48% of calorie intake and 39% of total food consumption by weight at age four. Despite UPFs contributing the majority of caloric intake, minimally processed foods made up the largest portion of food by weight (57%).
The adjusted models revealed positive associations between UPF intake and increased BMI, waist circumference, and fat mass, but no significant relationship with metabolic markers. Sensitivity analyses confirmed these findings, indicating that the proportional contribution of UPFs to overall diet was more influential than the total amount consumed.
Discussion
The study highlights the adverse health impacts of high UPF consumption in children, particularly concerning increased fat mass and BMI. UPFs, known for their poor nutritional profiles—including high levels of added sugars, saturated fats, and low levels of essential vitamins and minerals—are linked to increased energy density and reduced satiety, potentially leading to excessive calorie consumption.
Conclusion
The study concludes that high UPF consumption is associated with increased obesity measures in Chilean preschoolers over a two-year period, although no direct metabolic consequences were observed. Future research with longer follow-ups could provide further insights into the long-term effects of UPF consumption. Policymakers and health authorities are urged to promote environments that support minimally processed diets and limit children’s access to UPFs to mitigate these health risks.