Providing social support to others is associated with younger brain age in mid-to-late adulthood

Abstract Social connectedness is a robust predictor of health and longevity. While previous research has mainly focused on the benefits of receiving social support, the neuroprotective potential of providing social support to others remains underexplored. Using data from the Midlife in the United States (MIDUS) study, we tested whether total monthly hours spent providing instrumental and emotional support prospectively predict a brain age estimation gap (BrainAGE), a transdiagnostic biomarker of neurodegenerative disorders, psychiatric conditions, and mortality. BrainAGE was estimated with a machine-learning algorithm trained to predict chronological age from structural magnetic resonance imaging (MRI) scans. Combining hierarchical regression with bootstrapping and data-driven variable selection, we found that greater support provision was significantly associated with a younger-appearing brain for a given chronological age. This association persisted after controlling for a comprehensive set of covariates, including demographic characteristics, health conditions, lifestyle factors, and broader psychosocial contexts, including social support received. Notably, the hourly measure of support provision explained incremental variance in BrainAGE beyond role-based indices such as caregiving status or grandparenthood. Exploratory analyses further indicated that emotional support was more strongly associated with lower BrainAGE than instrumental assistance. Our findings highlight everyday prosocial behavior as a potential neuroprotective pathway in mid-to-late adulthood, with implications for intervention and policies for healthy aging.