Background and aim: The aim of this study was to assess the association between body shape trajectories and all-cause mortality in a Mediterranean cohort. Methods and results: Using a group-based modeling approach to fit body shape trajectories from the age of 5-40 years, among 11,423 participants from the Spanish SUN cohort, we assessed the subsequent risk of all-cause mortality. To create the trajectories, we used a censored normal model as a polynomial function of age. Cox regression models adjusted for sex, age, years of university education, marital status, smoking status, package-years of smoking, and recruitment period were used to estimate the hazard ratios (HR) for mortality according to each assigned trajectory. Overall, five distinct trajectories were identified: "lean-moderate increase," "medium-moderate increase," "medium-stable," "heavy-medium," and "heavy-moderate increase." During 106,657 person-years of follow-up, we observed 240 deaths. Compared with those who maintained a medium body shape in early and middle life ("medium-stable" trajectory), those who were heavy and had a moderate increase (" heavy-moderate increase" trajectory) showed higher mortality risk [HR = 1.91 (95% confidence interval: 1.14-3.21)]. In contrast, participants who were heavy in early life, and then decreased their body shape during early adulthood, and maintained a medium body shape throughout middle adulthood ("heavy-medium"), tend to exhibit lower mortality risk [HR = 0.60 (0.34-1.05)], similarly to those who were lean at childhood and had a moderate increase during adulthood ("lean-moderate increase") [HR = 0.82 (0.58-1.15)]. Conclusion: A moderate increase in body shape among subjects who were already heavy at early life was associated with higher risk of mortality in a Mediterranean cohort of university graduates. (C) 2020 The Italian Diabetes Society, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition and the Department of Clinical Medicine and Surgery, Federico II University. Published by Elsevier B.V. All rights reserved.