Scientists supported by Serrapilheira participated in this international study

Political instability, air pollution, and stark social inequality are key drivers of accelerated aging, according to a groundbreaking study published July 14, 2025, in the journal Nature Medicine. Conducted by 41 scientists from Latin America, Europe, Africa, and Asia—including Brazilian researchers supported by the Serrapilheira Institute—the study shows that a country’s political, environmental, and social conditions profoundly affect both mental and physical health, leading to higher rates of cognitive decline and cases of dementia.

Aging has long been viewed through the lens of individual factors such as genetics and lifestyle. The new study, however, shows that aging is far broader, shaped as well by the environments we inhabit and the countless exposures we experience in our daily lives.

A total of 161,981 participants from 40 countries, including Brazil, were included in the analysis. The researchers applied advanced artificial intelligence techniques and epidemiological modeling to analyze “biocognitive biological age gaps (BBAGs),” a measure of the difference between a person’s chronological age and their predicted age based on health, cognition, education, functional ability, and risk factors, such as cardiometabolic status or sensory impairments.

Using this information, ithe research identified a direct relationship between population aging and each country’s specific political, social, economic, and environmental contexts. 

“In this study, we investigated how environmental, social, and political conditions affect brain aging. Our results clearly indicate that where we live can accelerate aging, heightening the risk of cognitive and functional decline. In an unequal country like Brazil, these findings are extremely important for shaping public policy,” said Eduardo Zimmer, a professor at the Federal University of Rio Grande do Sul (UFRGS), a Serrapilheira-funded researcher, and one of the study’s authors.

In practice, the study suggests that in addition to individual lifestyle, aging is shaped by the cumulative impact of broader structural exposures.

Worldwide, faster aging appears to be closely linked with lower income levels. A range of conditions were associated with faster aging, including physical factors like poor air quality; social factors such as economic inequality, gender inequality, and migration; and sociopolitical factors such as lack of political representation, limited party freedom, restricted voting rights, and weak or fragile democracies. 

Compared with the global sample, European and Asian countries showed slower aging, whereas Egypt and South Africa showed faster aging. Brazil, however, fell somewhere in between. 

“This study is significant because it shows how broader life circumstances shape brain health. Where a person is born and where they live influences each individual’s brain in different ways. Living in Europe, Africa, or Latin America impacts aging differently due to disparities in resource availability and access to healthcare,” explains Wyllians Borelli, a UFRGS researcher supported by the Serrapilheira Institute and one of the study’s authors.

Brazilian researcher Lucas da Ros, from UFRGS and a member of the Zimmer Lab, also contributed to the study. In his view, “Before targeting individual risks, health authorities should prioritize reducing social inequalities and promoting regional development to foster healthier aging across the population.”

Political instability as an aggravating factor 

One of the study’s central findings is that political polarization, governance breakdowns, and institutional instability are directly linked to cognitive and physical decline in some regions. The authors note that these conditions affect public health by undermining resource allocation, weakening social cohesion, and destabilizing health systems, thereby widening disparities among social groups.

The researchers also note that countries with high levels of corruption, weak democracies, and low transparency tend to show higher rates of accelerated aging. As they wrote in the article, “Trust in government is associated with better health outcomes, whereas distrust and political polarization increase mortality and undermine public health responses.” 

This is the first time political instability has appeared in an international study with a large dataset as a risk factor for aging. The scientists suggest that long-term exposure to unstable governance can lead to chronic stress, contributing to cardiovascular and cognitive decline in a population. 

In addition to participating in the international study, Zimmer and Borelli recently published research in The Lancet Global Health showing that low educational attainment in Brazil is the leading risk factor for brain health in the population, driving higher rates of dementia, including Alzheimer’s disease.