Environmental experiences in childhood and adolescence play a meaningful role in shaping health across the lifespan, and focusing on manifestations of accelerated aging and disease risk earlier in the life course has the potential to inform prevention efforts. Our work focuses on markers of aging that manifest at the biological level in youth and young adults—long before chronic diseases of aging emerge. We believe that these markers of accelerated aging may be one target for understanding how early life adversity gets embedded “under the skin” to contribute to downstream adverse health outcomes.