Cumulative social advantage is associated with slower epigenetic aging and lower systemic inflammation

Background: Social relationships are established determinants of health across the lifespan, yet the cumulative and multidimensional effects of sustained social advantage on biological aging remain poorly understood. Methods: Drawing on data from 2117 adults in the Midlife in the United States (MIDUS) study, we used structural equation modeling to examine whether cumulative social advantage (CSA)—a latent construct encompassing social connection across familial, religious, emotional, and community domains—was associated with epigenetic aging, systemic inflammation, and neuroendocrine activity. Results: Higher CSA was linked to slower epigenetic aging, particularly as indexed by GrimAge (β = −0.09 to −0.10, q < 0.001) and DunedinPACE (β = −0.12, q = 0.010) clocks. CSA was also associated with lower levels of interleukin-6 (IL-6; β = −0.11, q = 0.010). No significant associations were observed for urinary cortisol, cortisone, or catecholamines. Conclusion: Sustained social advantage is associated with more favorable biological aging profiles, including slower epigenetic aging and reduced inflammatory signaling. These findings add to growing evidence that social resources are embedded in the physiological pathways that shape aging and health.