RESUMEN
BACKGROUND: Breastfeeding has been linked to a higher consumption of fruit and vegetables at ages 4 to 5 years. More recently, it has been suggested that it may also be associated with lower ultraprocessed food (UPF) consumption in childhood. OBJECTIVE: The aim of this study was to assess whether breastfeeding duration was associated with consumption of UPF in a sample of Mediterranean preschoolers. DESIGN: This study involved a cross-sectional analysis of baseline information of children in the Child Follow-Up for Optimal Development cohort. Children were enrolled at ages 4 to 5 years and information was gathered through an online questionnaire completed by parents. Dietary information was collected with a previously validated semi-quantitative food frequency questionnaire and foods were classified based on the degree of processing according to the NOVA classification. PARTICIPANTS/SETTING: This study used baseline information for 806 participants enrolled in the Child Follow-Up for Optimal Development cohort between January 2015 and June 2021 in Spain. MAIN OUTCOMES MEASURES: Main study outcome measures were difference in grams per day and in the percentage of total energy intake from UPF consumption related to breastfeeding duration, and odds ratio that UPF represents a high percentage of total energy intake. STATISTICAL ANALYSES: Crude and multivariable adjusted estimates were calculated with generalized estimating equations to account for intracluster correlation between siblings. RESULTS: The prevalence of breastfeeding in the sample was 84%. After adjusting for potential confounders, children who were breastfed for some time reported significantly lower consumption of UPF than children who were not breastfed at all. The mean differences were -19.2 g (95% CI -44.2 to 10.8) for children who were breastfed for <6 months, -42.5 g (95% CI -77.2 to -7.80) for those who were breastfed for 6 to 12 months, and -43.6 g (95% CI -79.8 to -7.48) for those who were breastfed for 12 months or more (P value for trend = 0.01). After adjusting for potential confounders, compared with children who were not breastfed, those who were breastfed for ≥12 months had consistently lower odds of UPF representing more than 25%, 30%, 35%, and 40% of total energy intake. CONCLUSIONS: Breastfeeding is associated with lower consumption of UPF in Spanish preschoolers.