Eating healthily in terms of fruit and vegetable consumption has beneficial effects for employees and their organisations. Yet, we know little about how employees' eating behaviour develops over longer periods of time (trajectories) as well as about how subgroups of employees in these trajectories differ (trajectory classes). Gaining such insights is critical to understand how employees address healthy eating recommendations over time as well as to develop individualised interventions that also consider the development of healthy eating (i.e. improvement versus impairment beyond mean levels). We analysed panel data (Longitudinal Internet Studies for the Social Sciences) from 1054 employees by means of growth mixture modelling. Our analyses revealed three relevant classes of healthy-eating trajectories: a favourable trajectory class, an unfavourable trajectory class and a strongly improving trajectory class. Furthermore, unfavourable healthy-eating trajectories were especially critical with respect to impaired psychological well-being. Specifically, we found robust results for impaired positive and negative affects, but not for self-esteem, in the unfavourable trajectory class. We discuss limitations and implications of these findings, thereby encouraging research and practice to further consider such fine-grained approaches (i.e. focusing on subgroups within a larger population) when addressing healthy-eating promotion over time.