New research suggests that the more languages people speak, the younger their brains appear. Learning more languages, especially when younger, and achieving fluency in a second language also seem to slow brain aging.

The research was presented at the recent Federation of European Neuroscience Societies (FENS) Forum 2026 by Dr Lucia Amoruso from the Basque Center on Cognition, Brain and Language, San Sebastián, Spain, who worked with a team from the Latin American Brain Health Institute at the Universidad Adolfo Ibañez, Chile, the Cognitive Neuroscience Center at the Universidad de San Andres, Argentina, and the Global Brain Health Institute at Trinity College Dublin, Ireland.

The study, Multilingualism protects against accelerated aging in cross-sectional and longitudinal analyses of 27 European countries shows that brains age more slowly in countries where people are typically multilingual.

The researchers began with a group of 728 people to create a brain aging clock. They used a technique called magnetoencephalography which measures brain activity by the faint magnetic fields produced when brain cells are active. The researchers used artificial intelligence to process data on brain activity in people of different ages to show what is a normal level of brain connectivity at any given age. They estimated bio-behavioral age gaps in 86,149 adults by training clocks on national survey–derived indicators spanning positive (functional ability, education, cognition) and adverse (cardiometabolic conditions, sensory impairments) factors, modelling multilingualism as a country-level exposure. Then the team used this clock to gauge the brain age of a second group of 144 people.

When they compared people’s real age with the age of their brain, they found that those who spoke two languages had brains that appeared around six years younger than those who spoke only one language. For people who spoke three languages, their brains were around seven years younger, and for those who spoke four languages, their brains were around 13 years younger.

Amoruso explained: “In simple terms, people who spoke more languages tended to have brains that looked younger than expected for their chronological age. The effect was not only related to the number of languages spoken. Higher language proficiency and earlier acquisition of a second language were also associated with more delayed brain aging. 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.”

The researchers took account of factors such as people’s age, sex, and education, but caution that they cannot rule out the potential influence of other factors that may have an impact on the brain, such as lifestyle and social engagement. Dr Amoruso and the team now hope to carry out similar work in people with neurodegenerative conditions, such as Alzheimer’s disease, where brain aging and resilience are especially important. They also plan to look at whether speaking two or more languages that are very similar could have a bigger effect on the brain, since managing closely related languages may require greater language control.