November 12, 2025, 2:42 am | Read time: 5 minutes
Worldwide, many people speak more than one language—up to 70 percent, according to estimates. A new Europe-wide study now suggests that multilingualism not only enriches culturally but could also be linked to a healthier aging process. A closer look at the results shows the role language plays in aging.
What Was Studied and Why?
A large-scale study examined whether speaking multiple languages could contribute to healthier mental and physical aging. The basis was the concept of cognitive reserve, which refers to the brain’s ability to better compensate for age-related changes or diseases like dementia. This reserve develops when the brain is regularly challenged—such as through the use of multiple languages in daily life.
Previous studies had provided hints of such a connection, but they often suffered from weaknesses: small participant numbers, unclear definitions of multilingualism, or failure to consider other influencing factors.1 The aim of the new study was therefore to examine more precisely, on a broad data basis, whether and to what extent multilingualism might be associated with a healthier aging process.
Instead of relying solely on classic diagnoses like dementia, the study used a new, innovative approach. It calculated how much a person’s biological age deviates from their actual age—depending on how healthy they live, how fit they are, whether they have chronic diseases, or remain mentally active. This difference is called the “biobehavioral age gap”—or BAG for short. The smaller the gap, the better the individual aging process.
What Is Biological Age?
Unlike chronological age, which is simply derived from the birth date, biological age describes the condition of the body—how old someone actually is, measured by health, lifestyle, and physical condition. A person can be 70 years old but biologically resemble the average 60-year-old–or vice versa.2
And this is where a noticeable trend emerged: People who speak more than one language generally fared better than monolinguals—their biological age often fell below what would be expected based on their birth year.
Study Design and Methods
The study evaluated data from over 86,000 older individuals across 27 European countries.3 It combined snapshots with long-term observations. A calculation model estimated each person’s biological age based on various characteristics:
- mental performance,
- physical activity,
- education,
- chronic diseases,
- sleep quality
- and daily habits.
Multilingualism was considered as a separate factor. To avoid distortions, researchers also controlled for environmental influences, such as migration, air quality, social inequality, or political stability in each country. Additionally, the study examined not only whether multilingual individuals appeared healthier at the time of the survey but also whether they aged more slowly over time.
Indications of Slowed Biological Aging in Multilinguals
The data analysis suggested that individuals who speak only their native language more often exhibited accelerated biological aging. In contrast, multilingual individuals—those who speak at least one additional language—aged more slowly on average. This connection was evident both in cross-sectional and longitudinal views.
Notably, the protective effect appeared to be dose-dependent: The more languages a person spoke, the younger their biological age seemed compared to their actual age. Interestingly, this effect was evident even when language skills were recorded only roughly and without further details. This suggests that the connection was relatively stable—even under simplified measurement conditions.
Even when factors like education, exercise, or chronic diseases were considered, it was clear: Multilingualism could be an independent protective factor. In countries with high migration or significant gender differences, the effect was somewhat weaker, but overall the connection remained.
2 Simple Steps to Keep Your Brain Young
Study Finds Possible Reason Why Girls Are More Prone to Depression Than Boys
Multilingualism as a Potential Lever for Prevention
The study suggests that multilingualism could be an independent, modifiable protective factor for healthy aging—similar to exercise, nutrition, or social activity. The key is not only learning new languages but also actively using them in everyday life.
Multilingualism could be a simple way to support mental health in old age. This applies regardless of education or background. At the same time, the study shows that the new BAG model is well-suited to detect differences in the aging process early and more accurately—on a broad population level.
On the Significance and Scope of the Results
As convincing as the results may seem, there are still important limitations. The study captured multilingualism only superficially. Neither the timing of language acquisition nor the frequency of use was considered. Such differences, such as whether someone speaks multiple languages daily or only occasionally understands a second language, could be crucial according to recent studies in determining how strongly multilingualism affects the aging process.4
Moreover, the study showed a correlation but not yet a cause-and-effect relationship. Whether multilingualism actively protects against aging or simply accompanies other healthy behaviors is unclear. Intervention studies—targeted investigations where adults deliberately learn a new language to see if their health trajectory measurably changes—would now be crucial.
Although many details remain open, a plausible connection between multilingualism and the course of biological aging was evident—even with rough data collection and across different countries. This observation could be a starting point for further research, particularly regarding age-related health processes.