Rising U.S. income inequality and the changing gradient of socioeconomic status on physical functioning and activity limitations, 1984-2007

► This study examines the interactive contextual effect of income inequality on physical functioning and activity limitations in the U.S. ► Increasing income inequality strengthens the protective effects of family income, employment, college education, and marriage on these two measures of health. ► High school education's protective effect (relative to less than a high school education) weakens in the context of increasing income inequality. ► Increasing income inequality exacerbates men's disadvantages in physical functioning and activity limitations. ► These findings shed light on research about growing health disparities in the U.S. in the last several decades.