Effect of unequal employment status on workers' health: Results from a Japanese national survey

► Despite Japan's status as an egalitarian society, health disparities are nonetheless caused by variations in socioeconomic status. ► The health status of employed workers in Japan has deteriorated, especially between 2004 and 2007, regardless of age and cohort effects. ► The increasing number of workers in precarious employment situations seems to be linked to a deterioration in workers' health generally. ► This trend has not been assessed until now.