Anti-aging creams. Retinols. Cosmetic surgeries. Our society is obsessed with anti-aging regimens that promise to make us appear younger and younger with each passing year. However, these solutions are merely temporary bandages, surface-level attempts to hide the physical signs of aging rather than addressing their deeper causes. In reality, the way we age is shaped by a complex set of factors including the communities we live in and the lifestyles we lead.
A recent international study led by Cuban neuroscientist Hernan Hernandez of the Latin American Brain Health Institute sheds new light on this idea. The team behind the study introduced the concept of Biobehavioral Age Gaps (BBAGs), the difference between an individual’s chronological age in years and their estimated “biobehavioral” age, which is based on various health and lifestyle factors. These factors include living conditions, access to healthcare, socioeconomic status, and geography, all of which can speed up or slow down the body’s aging process. A positive BBAG indicates accelerated aging—when the body functions as if it were older than one’s chronological age—while a negative BBAG reflects delayed aging, indicating better overall health and resilience. In this way, discrepancies between our biobehavioral age and chronological age can be measured and interpreted.
The study quantified biobehavioral ages by analyzing national survey data from a cohort of approximately 160 thousand healthy individuals across forty countries. Using a machine learning model, the researchers predicted each participant’s expected chronological age based on a range of biobehavioral factors, including physical abilities (e.g., the ability to climb stairs), cognitive performance, and the presence of risk factors for common health conditions, such as heart disease, hypertension, and hearing loss. These factors construct an individual’s exposome: the sum of all environmental exposures that shape health throughout one’s lifetime.
Factors in one’s exposome can be categorized in three broad ways: as physical, social, and sociopolitical environments. The physical environment includes weather conditions, walkability of the living environment, air quality, and sanitation. Social environment refers to the presence or absence of inequalities, such as those related to gender and socioeconomic class. Lastly, the sociopolitical environment reflects broader political conditions, including political freedom, the extent to which citizens are represented in government, the fairness of elections, and the overall strength of democratic institutions. Defined by the model, the difference between this predicted age and a person’s actual age is their BBAG. “The level of a person’s health and how they age is one of the most important values of our society ,” said Agustin Ibanez, Professor in Global Brain Health at Trinity College and the study’s director. He emphasized that as populations worldwide continue to age rapidly, promoting healthy aging is increasingly a societal priority. In this context, understanding measures such as BBAG scores can help countries identify where their citizens are most at risk of accelerated aging and, in turn, guide policies that foster long-term improvements in national health outcomes.
The study revealed that while personal habits, such as self-care, can influence biobehavioral aging, societal and geographical conditions exert far greater influence. For instance, European nations showed the slowest rates of biobehavioral aging, supported by lower stress levels, quality healthcare systems, clean air, and a lower prevalence of genetic dispositions to chronic disease. Conversely, Latin American and Asian countries experience accelerated aging due to economic stressors (i.e., high poverty rates) and the increasing prevalence of chronic diseases. “[The difference in average BBAG results] between Denmark and Sweden compared to Egypt and South Africa was more or less six years,” Ibanez said. These disparities illustrate how the social norms, socioeconomic systems, and health policies of a country together play an important role in determining the health and lifespans of inhabitants.
The implications of this study extend to our individual well-being, global health, and health policy. “Country-level indexes of accelerated aging can be used to provide brain health-like indexes that contextualize how the overall conditions of a country impact your overall aging,” Ibanez said. By illuminating differences in BBAGs across the globe and the interdisciplinary factors that influence aging, this study can help address global health inequities. “[Our study can be] leveraged to provide tailored assessments and identify primary risk factors for public health interventions in nations whose governments have limited budgets,” Ibanaz said. In this vein, biological, social, and political forces can work together to tailor health policies and preventative health systems across disciplines, helping them tackle broader public health inequities.
Ultimately, this study redefines aging from a purely individualistic phenomenon to a societal one, illustrating how epidemiology and the social determinants dictate biobehavioral age. The BBAG metric developed in this study by Hernandez’s team serves as an example of how life expectancy and health outcomes can differ drastically across mere zip codes, proving that an individual’s environment—and the myriad of socioeconomic, environmental, and political conditions it presents—is a stronger indicator of health in aging than what cosmetics salespeople might make you believe.