 Serum 25OHD, dietary and supplemental vitamin D were shown to influence cognitive outcomes in large epidemiological studies. Sexage-specific and race-specific associations of vitamin D status and intake were examined with longitudinal change in various cognitive domains in a large sample of ethnically and socio-economically diverse US urban adults. Two prospective waves of data from Healthy Aging in Neighborhoods of Diversity across the Life Span HANDLS study were used, specifically visit 1: 2004-2009 and visit 2: 2009-2013, mean follow-up timeSD: 4.640.93y. Cognitive performance was assessed using 11 test scores covering domains of global cognition, attention, learningmemory, executive function, visuo-spatialvisuo-construction ability, psychomotor speed and languageverbal. Serum 25OHD, vitamin D intake and use of supplements containing vitamin D were the key exposures. Multiple mixed-effects linear regression models were conducted, N1,231-1,803, k1.5-2.0 observationparticipant. 