Racial/ethnic differences in the association of lifestyle factors with biological aging in NHANES, 1999-2018.

Racial and ethnic disparities in healthy aging represent an emerging public health crisis that will only grow worse as our population grows older. Healthy lifestyle behaviors are proposed as a key strategy to promote healthy aging. However, the potential of lifestyle interventions to address aging health disparities is uncertain. We analyzed data from 42 625 adult participants (aged 20-85 years) participating in National Health and Nutrition Examination Survey (NHANES), 1999-2018 to evaluate relationships among healthy lifestyle behaviors and biological aging across White, Black, and Hispanic-identifying groups. We measured healthy lifestyle as adherence to a Mediterranean diet and level of leisure-time physical activity using established methods. We measured healthy aging using the PhenoAge biological age algorithm applied to blood chemistry data. We tested associations within each race/ethnic identity group and compared associations across groups using regression models with interaction terms. We found that within each race/ethnic identity group, greater adherence to a Mediterranean diet and higher levels of leisure-time physical activity were associated with younger biological age, independent of demographic and socioeconomic confounders, obesity, and smoking. However, these associations were stronger among White- as compared to non-Hispanic Black- and Hispanic-identifying adults. Results suggest that healthy lifestyle factors are likely to promote healthy aging across the population. However, lifestyle factors alone may not be sufficient to completely address race/ethnic disparities in healthy aging. Future studies will need to investigate additional ways to reduce racial and ethnic disparities in healthy aging.