A systematic review on the effects of social discrimination on telomere length

Discrimination is unfair treatment against a certain group based on race, age, gender, sexual orientation, or other social identities. Discrimination is pervasive in society, elevates psychosocial stress, and is associated with negative mental and physical health outcomes. However, more research is needed to understand the biological mechanisms underlying discrimination-related health disparities. Telomere science may contribute to elucidate some of these aspects. Telomeres are protein-DNA complexes that shorten after cell division and are valuable markers of cellular aging. Short telomeres have been associated with the onset of age-related diseases. Evidence shows that chronic psychological stress may accelerate telomere shortening. Since discrimination can lead to psychological strain with cumulative impact on general health, we hypothesized that groups that report more discrimination show reduced telomere length (TL) as a consequence of psychosocial stress elevation. Through a systematic review of the literature we found 12 articles that met our criteria. Eligible studies measured racial, gender, unfair policing, and multiple forms of discrimination in association with TL. Our review showed mixed results, suggesting that there is weak evidence of a main association between discrimination and TL. However, discrimination may interact with several variables (such as depressive symptoms, acculturation, higher socioeconomic status, internalization of negative racial bias, and not discussing discrimination experiences with others) and contribute to shorten telomeres. Discrimination is a complex social construct composed of a vast sum of experiences, impressions, and contexts that in combination with other sources of stress may have an impact on TL. Telomeres may be a plausible pathway to investigate health discrepancies in discriminated groups in society, but more evidence is needed to investigate the potential harm of discrimination on cells.