BACKGROUNDS AND AIM:The association between trajectories of body-shape from early childhood to early adulthood (first 40 years of life) and subsequent depression risk has not been explored before. We assessed this association in a prospective cohort of university graduates. METHODS:We used a group-based modeling approach to assess the body shape trajectories from age 5 to 40 years, among 3888 women and 4124 men of the "Seguimiento Universidad de Navarra" (SUN) cohort study. All participants were free of depression at the beginning of the follow-up, and the occurrence of a new medical diagnosis of depression was evaluated every two years. RESULTS:Four distinct trajectories for women and men were found ("lean-moderate increase", "medium-stable", "heavy-medium" and "heavy-marked increase" for women and "lean-marked increase", "medium-marked increase", "medium-stable" and "heavy-stable" for men). Among 78,475 person-years of follow-up a total of 351 incident cases of depression were identified. Among women, compared to those who maintained a medium body shape during life span ("medium-stable" trajectory), women who were heavy at childhood and had a marked increase in their body shape during early adult life ("heavy-marked increase" trajectory) showed significantly higher risk of a new-onset depression [HR = 1.92 (1.18-3.13)]. No association was observed in men between body-shape trajectories and subsequent risk of depression. CONCLUSIONS:Our results suggest that in a Mediterranean cohort, women who were heavy at early childhood and showed marked increases in body shape during early adulthood were at higher risk of developing depression later in life.