Aims: The globalized economy has stimulated mobility in the labour market in many countries and Denmark has one of the highest rates of mobility between workplaces among the OECD countries. This raises the question of the potential health effects of mobility and the effect of disease on mobility. Methods: This study was register-based with a longitudinal design using data on the entire Danish population in 1992–2006. The data included mobility between employers and workplaces and seven different diseases based on admissions to hospital and drug prescriptions. Results: After adjusting for relevant confounders, an exposure–response relationship was seen between mobility and the incidence of ischaemic heart disease, stroke, duodenal ulcer, anxiety/depression and, most strongly, with alcohol-related disorders. The effects were not very strong, however, with odds ratios varying from 1.2 to 1.6. As expected, no effect was seen for colorectal cancer. We also found an effect of both somatic and mental disorders on mobility, but not for the two cancer types. Mobility did not seem to prevent being out of the labour force after diagnosis. Conclusions: Frequent mobility in the labour market increases the risk of cardiovascular disease, common mental disorders and alcohol-related disorders and these diagnoses also seem to increase the risk of subsequent mobility.