ITHACA, N.Y. – The cumulative effect of social advantages across a lifetime – from parental warmth in childhood to friendship, community engagement and religious support in adulthood – may slow the biological processes of aging. These social advantages appear to set back "epigenetic clocks" such that a person's biological age, as measured by analyzing DNA methylation patterns, is younger than their chronological age.
The research, which appeared in the October issue of the journal Brain, Behavior and Immunity - Health, drew on data from more than 2,100 adults in the long-running Midlife in the United States, or MIDUS, study.
Anthony Ong , psychology professor at Cornell University, and fellow researchers found that people with higher levels of what they called "cumulative social advantage" showed slower epigenetic aging and lower levels of chronic inflammation.
The study focused on so-called epigenetic clocks, molecular signatures that estimate the pace of biological aging. Two in particular – GrimAge and DunedinPACE – are considered especially predictive of morbidity and mortality. Adults with stronger, more sustained social networks showed significantly younger profiles on both clocks.
"Cumulative social advantage is really about the depth and breadth of your social connections over a lifetime," Ong said. "We looked at four key areas: the warmth and support you received from your parents growing up, how connected you feel to your community and neighborhood, your involvement in religious or faith-based communities, and the ongoing emotional support from friends and family."
The researchers hypothesized that sustained social advantage becomes reflected in core regulatory systems linked to aging, including epigenetic, inflammatory and neuroendocrine pathways. Remarkably, they found that higher social advantage was linked to lower levels of interleukin-6, a pro-inflammatory molecule implicated in heart disease, diabetes and neurodegeneration. Interestingly, however, there were no significant associations with short-term stress markers like cortisol or catecholamines.
Unlike many earlier studies that looked at social factors in isolation – whether a person is married, for example, or how many friends they have – this work conceptualized "cumulative social advantage" as a multidimensional construct. And by combining both early and later-life relational resources, the measure reflects the ways advantage clusters and compounds.
"What's striking is the cumulative effect - these social resources build on each other over time," Ong said. "It's not just about having friends today; it's about how your social connections have grown and deepened throughout your life. That accumulation shapes your health trajectory in measurable ways."
This doesn't mean a single friendship or volunteer stint can turn back the biological clock. The authors suggest that the depth and consistency of social connection, built across decades and different spheres of life, matters profoundly. The study adds weight to the growing view that social life is not just a matter of happiness or stress relief but a core determinant of physiological health.
"Think of social connections like a retirement account," Ong said. "The earlier you start investing and the more consistently you contribute, the greater your returns. Our study shows those returns aren't just emotional; they're biological. People with richer, more sustained social connections literally age more slowly at the cellular level. Aging well means both staying healthy and staying connected - they're inseparable."
