Speaking more than one language is associated with brains that appear biologically younger, by about six years for bilinguals, seven for trilinguals, and up to 13 for quadrilinguals, according to research presented in Barcelona at the Federation of European Neuroscience Societies (FENS) Forum 2026.
The findings, reported by The Guardian on July 6, add to a growing body of evidence that multilingualism contributes to cognitive reserve in aging. The researchers used a novel method: an AI-powered “brain-age clock” based on magnetoencephalography (MEG) recordings, which measures the age of the brain by how its neural connectivity patterns compare to a normative dataset.
Disclosure: The study described is a conference poster presentation (Abstract #5474) at FENS Forum 2026 and has not yet been published in a peer-reviewed journal.
The Study
Led by Lucia Amoruso, deputy scientific director at the Basque Center on Cognition, Brain and Language (BCBL) in San Sebastián, Spain, the team first created a brain-age clock from MEG data of 728 participants spanning a wide age range. MEG measures the magnetic fields produced by electrical activity in the brain, providing millisecond-resolution data on neural connectivity patterns. An AI model was trained to identify the connectivity signatures associated with each age.
The clock was then applied to a second group of 144 people from the Basque region speaking between one and four languages (Spanish, Basque, French, and English). After adjusting for age, sex, and education level, the researchers found a clear gradient: the more languages a person spoke, and the earlier they had acquired them, the younger their brain appeared relative to their chronological age.
“Higher language proficiency and earlier acquisition of a second language were also associated with more delayed brain aging,” Amoruso told the FENS conference. “This suggests that multilingual experience matters as a gradient: it is not simply about being bilingual or not, but about the depth and duration of language experience.”
Six, Seven, Thirteen
The specific numbers are striking:
- Speaking two languages: brain appears approximately 6 years younger
- Speaking three languages: approximately 7 years younger
- Speaking four languages: approximately 13 years younger
The quadrilingual figure should be interpreted cautiously, the sample size of people speaking four languages was likely small. But the dose-response relationship across all groups supports the interpretation that the effect is real.
Mechanism and Context
The study does not prove that learning a second language causes the brain to age more slowly, causation could run in the opposite direction, or a third factor (such as general cognitive engagement, socioeconomic status, or personality traits associated with both language learning and healthy aging) could explain the association.
However, the findings are consistent with a larger body of research on cognitive reserve, the brain’s ability to maintain function despite age-related changes. A related study by the same research group, published in Nature Aging in 2025 and analyzing 86,149 participants across 27 European countries, found that multilingualism was associated with a reduced risk of accelerated cognitive aging (odds ratio 0.46 in cross-sectional analysis).
The MEG-based brain-age clock approach is relatively new, and the specific method used in this study has not been independently replicated. But it offers a more direct measure of brain health than the cognitive test scores used in most prior bilingualism research.
Implications
The growing evidence that bilingualism contributes to cognitive reserve has practical implications for education policy and public health. If learning additional languages genuinely protects against age-related cognitive decline, then language education in childhood, when acquisition is easiest and the protective effect appears strongest, could be seen as a form of investment in long-term brain health.
The research also raises questions about whether language learning later in life provides similar benefits. The current study’s finding that earlier acquisition is linked to greater protection suggests there may be a sensitive period, but the data on late-life language learning as a cognitive intervention remains limited.
Disclosure: Based on a conference presentation (FENS Forum 2026, Abstract #5474, July 8, 2026) and reported by The Guardian on July 6, 2026. Not yet peer-reviewed. The same research group’s related study: “Multilingualism protects against accelerated aging in cross-sectional and longitudinal analyses of 27 European countries,” Nature Aging, 2025. DOI: 10.1038/s43587-025-01000-2.