Determining whether population dynamics provide competing explanations to place effects for observed geographic patterns of population health is critical for understanding health inequality. We focus on the working-age population-the period of adulthood when health disparities are greatest-and analyze detailed data on residential mobility collected for the first time in the 2000 U.S. census. Residential mobility over a five-year period is frequent and selective, with some variation by race and gender. Even so, we found little evidence that mobility biases cross-sectional snapshots of local population health. Areas undergoing large or rapid population growth or decline may be exceptions. Overall, place of residence is an important health indicator; yet, the frequency of residential mobility raises questions of interpretation from etiological or policy perspectives, complicating simple understandings that residential exposures alone explain the association between place and health. Psychosocial stressors related to contingencies of social identity associated with being black, urban, or poor in the United States may also have adverse health impacts that track with structural location even with movement across residential areas.

Residents of distressed urban areas suffer early aging-related disease and excess mortality. Using a community-based participatory research approach in a collaboration between social researchers and cellular biologists, we collected a unique data set of 239 black, white, or Mexican adults from a stratified, multistage probability sample of three Detroit neighborhoods. We drew venous blood and measured telomere length (TL), an indicator of stress-mediated biological aging, linking respondents' TL to their community survey responses. We regressed TL on socioeconomic, psychosocial, neighborhood, and behavioral stressors, hypothesizing and finding an interaction between poverty and racial-ethnic group. Poor whites had shorter TL than nonpoor whites; poor and nonpoor blacks had equivalent TL; and poor Mexicans had longer TL than nonpoor Mexicans. Findings suggest unobserved heterogeneity bias is an important threat to the validity of estimates of TL differences by race-ethnicity. They point to health impacts of social identity as contingent, the products of structurally rooted biopsychosocial processes.