Hence, the aim of this study was to examine the association of overweight and obesity with WF, and to determine if the associations differ for workers with different working-time arrangements (i.e. shift workers, on-call workers and day workers). We hypothesized that overweight and obesity are associated with poor WF and the associations are stronger in shift workers than in on-call and day workers. The findings could help identify working time arrangements with high-risks regarding WF.