Exclusive breastfeeding and introduction of ultra-processed foods in the first year of life: a cohort study in southwest Bahia, Brazil, 2018.

Objective: To analyze association between exclusive breastfeeding (EBF) and the introduction of ultra-processed foods in children under 12 months old.

Methods: This was a Cohort study, conducted with children in Vitória da Conquista, Bahia, Brazil. The main exposure was EBF (days: <120; 120-179; ≥180). The outcome variable was the introduction of four or more types of ultra-processed foods in the first year of life. Poisson regression analysis was used.

Results: 286 children were evaluated, of whom 40.2% received four or more ultra-processed foods and 48.9% EBF for less than 120 days. EBF for less than 120 days (RR=2.94 - 95%CI 1.51;5.71) and for 120-179 days (RR=2.17 - 95%CI 1.09;4.30) was associated with the outcome after adjustment by socioeconomic, maternal, paternal and child variables.

Conclusion: EBF for less than 180 days increased the risk of introducing four or more ultra-processed foods in the first year of life.