AUC Contributes to A Groundbreaking International Study About Novel Factors Accelerating Aging

 A team from the American University in Cairo (AUC), led by Mohamed Salama, professor at the Institute of Global health and Human Ecology and senior fellow at the Global Brain Health Institute (GBHI) and Sara Moustafa, a postdoc in AUC’s aging research group, contributed to a groundbreaking international study published in Nature Medicine that reveals that our environments—including pollution, social inequality, and weak democratic institutions—significantly accelerate how our lifespan ages.

The research, involving 161,981 individuals across 40 countries, introduces a global exposome framework and shows that multiple exposures can predict bio-behavioral age gaps (BBAGs), a novel measure of accelerated aging. BBAGs are the difference between a person’s actual age and the age-predicted from their health, cognition, education, functionality, and risk factors like cardiometabolic health or sensory impairments.

This study—led by a multinational team from Latin America, Africa, Europe, Asia, and North America—analyzed environmental, social, and political factors and their impact on brain aging using advanced artificial intelligence and epidemiological modeling. The results show that where you live—your exposome—can age you several years faster, increasing the risk for cognitive and functional decline.

The AUC team contributed to this work building on the impactful work done at AUC focusing on aging and brain health. “Diversity in research is not a luxury anymore,” said Salama. “Including countries from Africa and the Middle East is essential to understand the global risks and challenges for brain health. Our team at AUC has been successful in contributing to international research in this field promising to better understand determinants of healthy aging in Egypt and adding to the global knowledge.”

Agustin Ibanez, corresponding author of the study and researcher at the GBHI and Latin American Brain Health Institute noted that people need to stop thinking of brain health as a purely individual responsibility and consider a more ecological and neurosyndemic framework. “Our biological age reflects the world we live in. Exposure to toxic air, political instability, and inequality, of course, affect society, but also shapes our health,” he said.

The findings of this study present the first evidence that combined structural exposures beyond individual lifestyle are deeply embedded in our aging process. In an age of rising populism, environmental degradation, and global displacement, understanding how environments age the brains is a scientific, political, ethical, and health imperative.

“This is not a metaphor: environmental and political conditions leave measurable fingerprints across 40 countries, revealing a clear gradient of accelerated aging from Africa to Latin America, Asia, and Europe,” said Hernan Hernandez, first author of the study.

Several types of exposures were linked to faster aging: physical factors such as poor air quality; social factors, including economic inequality, gender inequality, and migration; sociopolitical factors, such as lack of political representation, limited party freedom, restricted voting rights, unfair elections, and weak democracies. Importantly, higher BBAGs were associated with real-world consequences: they predicted future declines in both cognitive abilities and daily functioning. People with larger age gaps were likelier to show significant losses in these areas over time.

“Whether a person ages in a healthy or accelerated way is shaped not only by individual choices or biology, but also by their physical, social, and political environments—and these effects vary widely between countries,” said Sandra Beaz, co-corresponding author and Atlantic Fellow of the GBHI at Trinity College.

This study redefines healthy aging as an environmental, social, and political phenomenon. Public health strategies must expand beyond lifestyle prescriptions to address structural inequalities and governance deficits.

For Hernando Santamaria-Garcia, co-first author and a GBHI fellow, “Governments, international organizations, and public health leaders must urgently act to reshape environments, from reducing air pollution to strengthening democratic institutions.” He added that these go beyond climate or governance issues to inform urgent health interventions.

The study affirmed that to promote healthy aging and reduce dementia risk worldwide, we must intervene upstream, where inequality is produced, where politics shape lives, and where environments silently erode healthy aging.