Association between helping behaviors and epigenetic aging: Findings from the United States and Northern Ireland

Background Prosocial behaviors such as volunteering and informal helping have been associated with positive health outcomes, but their links with biological aging remain underexplored, particularly across cultural contexts. The United States and Northern Ireland provide distinct social and institutional contexts for helping behaviors, allowing us to examine whether associations between volunteering, informal helping, and biological aging are context-specific or consistent across settings. Methods Using data from the 2014 and 2016 waves of the Health and Retirement Study (U.S.) and the 2016 wave of its family study, the Northern Ireland Cohort for the Longitudinal Study of Aging (NICOLA), we examined the associations between formal volunteering and informal helping and five epigenetic clocks: Horvath, Hannum, PhenoAge, GrimAge, and DunedinPACE. Results In the U.S., moderate engagement (1–99 hours/year) in both formal and informal helping was associated with decelerated epigenetic aging, especially for PhenoAge, GrimAge, and DunedinPACE, which are designed to capture morbidity- and mortality-related biological aging and physiological decline. However, high levels of informal helping (200+ hours/year) were linked to accelerated aging, suggesting possible stress or role strain. Formal volunteering exhibited consistent protective effects, even at higher frequencies. In Northern Ireland, volunteering 1–4 hours/week was linked to decelerated GrimAge, a mortality-related epigenetic aging measure, with no significant associations for other clocks. Cultural patterns also emerged: Americans were more likely to participate in formal volunteering, while Irish participants engaged more in informal helping. Conclusion These findings highlight the nuanced, context-dependent associations between helping behaviors and biological aging and suggest that the health benefits of helping others depend on the type, intensity, and cultural context of engagement.