A recent Canadian study has found a link between the consumption of ultra-processed foods (UPFs) in early childhood and slightly higher behavioral symptom scores later on. The research, published in JAMA Network Open, analyzed data from 2,077 children across multiple Canadian cities, including Vancouver, Manitoba, Toronto, and Edmonton.
Researchers used dietary and behavioral data collected from children at ages three and five. They assessed food intake using a 112-item questionnaire and categorized foods based on the NOVA classification system. Behavioral outcomes were measured using the Child Behavior Checklist (CBCL), which is based on caregiver reports.
The study found that at age three, children consumed an average of 1,489 kilocalories per day, with UPFs making up about 46% of their total calorie intake. By age five, higher UPF consumption was associated with small increases in CBCL scores for internalizing behaviors such as anxiety and withdrawal, externalizing behaviors like aggression and hyperactivity, and overall behavioral symptoms. The increase in scores was generally less than one T-score point for every 10% rise in calories from UPFs.
Subgroup analyses indicated that greater intake of artificially sweetened and sugar-sweetened beverages, breads, and ready-to-eat foods correlated with increased internalizing symptoms. The researchers did not find differences in these associations between boys and girls.
The study also examined what would happen if some UPF calories were replaced by unprocessed or minimally processed foods (MPFs). "In substitution models, replacing 10% of calorie intake from UPFs with unprocessed or minimally processed foods (MPFs) was associated with modestly lower behavioral symptom scores," according to the research team. Sensitivity analyses confirmed these findings even after accounting for factors such as sodium, saturated fat, total sugar intake, changes in UPF consumption over time, and screen time at age five.
"Although the effects were modest, the findings highlight that early dietary patterns may influence child development, reinforcing the importance of policies promoting healthier, minimally processed diets," stated the authors.
The cohort included 53% males; ethnically it was composed of 66% White children, 23% multiracial children, and 11% from other groups. Mothers of participating children tended to have higher education levels and household incomes compared to those excluded from analysis.
Public health strategies encouraging whole-food diets are supported by these results. The authors note: "The results support public health strategies promoting whole-food dietary patterns, including guidance from Health Canada’s Canada’s Food Guide and broader clinical and public health messaging encouraging minimally processed dietary patterns for mental and physical health."
They suggest that strengthening early-life nutrition efforts—such as family guidance programs, improved childcare nutrition standards, and restrictions on marketing highly processed foods to young children—could help support healthy development. The researchers call for future studies with more precise dietary assessments to further clarify long-term impacts on behavior and mental health.
