Background: Because of ageing populations, most high-income countries are facing an imminent scarcity of labour. Maintenance of health and performance in young adults therefore becomes a crucial prerequisite for sustainable societies. One major obstruction to this accomplishment is the striking health inequalities between young women and young men. Previously these inequalities have mainly been studied in a cross-sectional way, focusing on ill-health. In this study, we compared the prevalence of maintained health and performance between young adult women and men and the predictors for this outcome. Methods: The cohort consisted of 1266 participants from a homogenous sample of university students in Sweden. A combined assessment of self-rated ‘very good’ health and un-impaired performance took place at three time points (i.e. maintained health and performance). Potential predictors covered stable conditions in health-related behaviours, conditions at work/school and work-home interference. Results: Young women had less maintained health and performance than young men. No major differences in predictors were found. However, there was a tendency for psychosocial factors to be the most important predictors, especially in women. Conclusions: That young women had less maintained health and performance in a homogenous sample beyond well-known differentiating factors suggests explanations other than observable structural differences between the sexes. This was also indicated by the importance attached to perceived demands, and work-home interference, especially in women. The combination of less scheduled, and more unscheduled, schoolwork (i.e. time-flexibility) negatively affected the maintenance of health and performance in our study population, suggesting a focus for future studies.