Studies indicate an ethnic density effect, whereby an increase in the proportion ofracial/ethnic minority people in an area is associated with reduced morbidity among itsresidents, though evidence is varied. Discrepancies may arise due to differences in thereasons for migration, and socioeconomic profiles of the racial/ethnic groups and theplaces where they live. It is important to increase our understanding of how these factorsmight promote or mitigate ethnic density effects. Cross-national comparative analysesprovide greater heterogeneity in historical and contemporary characteristics in thepopulations of interest, and it is when we consider this heterogeneity in the contexts ofpeoples' lives that we can more fully understand how social conditions andneighbourhood environments influence the health of migrant and racial/ethnic minoritypopulations.This study analysed two cross-sectional nationally representative surveys in the USand in England, to explore and contrast the association between two ethnic densitymeasures (black and Caribbean ethnic density) and health and experienced racism amongCaribbean people. Results of weighted multilevel logistic regressions show thatnominally similar measures of ethnic density perform differently across health outcomesand experienced racism measures in the US and in England. In the US, increasedCaribbean ethnic density was associated with improved health and decreased experiencedracism among Caribbean Americans, but the opposite was observed for CaribbeanEnglish. On the other hand, black ethnic density showed a trend for a protective effect onthe health and racism for Caribbean English, but not for Caribbean Americans. Bycomparing mutually adjusted Caribbean and black ethnic density effects in the US andEngland, the present study allowed us to examine the social construction of race andethnicity as it depends on the racialised and stigmatised meaning attributed to it, and theassociation that these different racialised identities have on health. © 2013 Nova Science Publishers, Inc. All rights reserved.