A groundbreaking investigation led by researchers at the University of Southern California’s Leonard Davis School of Gerontology reveals a stark and growing disparity in the biological aging rates of Americans according to their educational attainment. This extensive study highlights that individuals with lower levels of education are experiencing accelerated biological aging relative to their better-educated counterparts—a gap that has nearly doubled over the past three decades. These findings underscore pervasive social inequalities that extend deep into the very fabric of human health and longevity.
Biological aging, distinct from chronological age, serves as a more nuanced measure of how an individual’s body ages at the cellular and systemic levels. Unlike simply tallying years since birth, biological aging captures the progressive deterioration of physiological functions across various organ systems, reflecting the cumulative burden of life’s exposures and health behaviors. Consequently, two 65-year-olds can exhibit markedly different biological ages, with one displaying molecular and functional profiles typical of someone significantly younger, whereas the other may manifest premature aging phenotypes linked to disease and frailty.
The study’s lead investigator, University Professor Eileen Crimmins, emphasizes that biological age provides critical insight beyond traditional age metrics, offering a refined lens to predict disease susceptibility, disability onset, and overall health trajectories. The research team utilized rich datasets from the National Health and Nutrition Examination Survey (NHANES), analyzing biological aging markers among adults aged 50 to 79 during two distinct periods: the late 1980s to mid-1990s, and more recently between 2015 and 2018. Their comparative analysis uncovered a slowing of biological aging across the population overall; however, these health gains were disproportionately accrued by those with higher educational credentials.
The analysis demonstrated that in the earlier time frame, the biological age gap between individuals with less than a high school diploma and those holding college degrees hovered around one year. Fast forward to the 2015–2018 period, and this disparity had escalated to an approximate two-year difference. Such an increase attests to widening educational inequalities in health outcomes and suggests that the social determinants governing aging have become increasingly stratified. Mateo Farina, assistant professor and co-author, highlights this troubling trend, noting that while population health improvements have been made, they have stemmed primarily from advantaged educational groups, leaving less-educated adults behind in terms of physical aging.
This widening divide is particularly alarming given that educational inequality’s impact on health has been a long-standing area of public health concern for decades. What sets this study apart is its innovative focus on biological aging—an integrative measure combining biochemical, physiological, and molecular indicators—rather than relying solely on traditional morbidity and mortality data. By doing so, the research provides a deeper understanding of how social disparities translate into tangible biological effects that can predicate chronic disease burden and premature functional decline.
Education wields considerable influence over myriad aspects that shape health outcomes across the lifespan, ranging from employment opportunities and income levels to residential environments and healthcare access. Moreover, educational attainment often correlates with health-promoting behaviors such as lower tobacco use, healthier dietary patterns, and increased physical activity. Importantly, the study tested potential mediators like changes in smoking prevalence, obesity rates, and medication usage to explain the growing gap but found that these factors could not fully account for the widening biological age disparities. This suggests that education itself acts as a foundational social determinant, shaping lifelong exposures and stressors that cumulatively modulate biological aging processes.
Professor Crimmins elaborates that education structures opportunities and risk environments in ways that profoundly affect physiological resilience over decades. It operates not just as a marker but as a causal force influencing how quickly or slowly our bodies wear down. Such effects may be mediated through complex psychosocial mechanisms, economic resources, access to preventive care, and even epigenetic modifications induced by chronic stress and adversity linked to socioeconomic status. Consequently, the differential in educational attainment imprints long-lasting effects on population health dynamics and longevity patterns.
Forecasting into the future, the implications of rising educational disparities in biological aging raise critical concerns. Individuals with lower educational levels may face not only reduced lifespan but an extended duration of poor health and disability, imposing significant challenges on caregiving networks, healthcare systems, and social support infrastructures. These trends could exacerbate existing health inequities, deepen socioeconomic divides, and strain resources dedicated to aging populations.
Co-author Mateo Farina stresses that addressing these disparities transcends individual lifestyle choices, situating education firmly within the realm of public health interventions. Investments aimed at improving educational equity could serve as potent strategies to narrow health gaps, promote healthier aging, and mitigate the societal costs of advanced biological aging in disadvantaged groups. By reframing education as a public health priority, policymakers can target upstream determinants with the potential to generate widespread, intergenerational benefits.
Methodologically, the research relied on sophisticated statistical analyses of nationally representative biological and demographic data, applying contemporary biomarkers of aging to assess systemic physiological integrity. This approach allowed for precise estimation of biological age differences over time and illuminated the shifting landscape of health inequality. The findings enrich the demography and gerontology literature by integrating social science perspectives with biomedicine, offering a holistic view of the aging process shaped by social conditions.
Ultimately, these insights illuminate the profound interplay between social structures and biological aging trajectories, challenging notions that aging is determined solely by genetics or personal behavior. Instead, the research affirms that educational disparities represent a fundamental axis along which health deteriorates unevenly across society. Bridging this gap demands coordinated efforts across education policy, health systems, and social welfare to ensure equitable aging and improved quality of life for all Americans as the population ages.
This pivotal study, soon to be published in the journal Demography, marks a critical step forward in understanding the social determinants of aging at a biological level. It highlights the urgency of tackling educational inequalities not only as issues of social justice but also as vital public health imperatives with direct bearings on population aging patterns and healthcare futures. As societies worldwide grapple with aging demographics, recognizing and mitigating these disparities will be paramount to fostering healthier, longer lives for diverse populations.
Subject of Research: People
Article Title: Increasing Educational Inequality in Biological Aging Among U.S. Adults Aged 50–79 From 1988–1994 to 2015–2018
News Publication Date: 31-Jul-2025
Web References:
https://doi.org/10.1215/00703370-12175545
References:
Farina, M., Crimmins, E. et al. (2025). Increasing Educational Inequality in Biological Aging Among U.S. Adults Aged 50–79 From 1988–1994 to 2015–2018. Demography.
Keywords: Older adults, Aging populations, United States population, Population studies, Demography, Educational levels, Educational attainment, Education, Gerontology, Human health, Public health
