A new study has found that individuals who speak only one language are more likely to age faster. The analysis, published in Nature Aging, examined data from over 86,000 older adults across 27 European countries. The authors suggest that learning more than one language could benefit countries facing ageing populations.
Psychological medicine lecturer at the University of Auckland, Dr Etu Ma’u, says that the rate at which our brains age is affected by the cumulative and incremental damage they sustain over a lifetime.
“While many brain health recommendations focus on reducing brain damage by improving lifestyle behaviours, this recently published study by Amoruso and colleagues demonstrates that the ability to speak more than one language improves cognitive reserve by slowing brain ageing, and the benefits increase with the number of languages spoken.”
The language of longevity
Researchers analysed the 86,000 adults using a biobehavioural age gap (BAG) model, which estimates biological age based on physiological, lifestyle, and socioeconomic factors. Comparing this with chronological age, they found that monolinguals were twice as likely to show signs of accelerated ageing. At the same time, bilingual and multilingual individuals had lower BAGs, indicating slower cognitive decline.
The benefits increased with the number of languages spoken. Those fluent in three or more languages experienced greater protection than those who spoke just two. Even learning a single additional language appeared to reduce signs of accelerated ageing. The study also controlled for factors such as education, wealth, and immigrant status, thereby making the results more robust.
However, there are limitations. Language use was self-reported, with no measure of fluency or frequency of language use, and the study’s cross-sectional design cannot establish cause and effect. Genetics, social engagement, and other factors may also influence brain health. Still, the findings underline multilingualism as a potential tool for cognitive resilience, suggesting that encouraging language learning could be a simple yet powerful way to support healthy brain ageing.
How polyglots benefit
Speaking more than one language offers a host of cognitive, social, and health benefits, many of which become increasingly important as we age. By regularly using multiple languages, the brain builds cognitive reserve, thereby strengthening neural connections and enhancing resilience against age-related decline, including conditions such as dementia.
Beyond brain health, bilingualism enhances memory, attention, and problem-solving skills. Switching between languages requires mental flexibility, which sharpens executive functions such as multitasking, focusing, and adapting to new information. It also improves metalinguistic awareness, making it easier to learn additional languages and develop literacy skills.
Socially and culturally, speaking multiple languages expands communication opportunities, allowing individuals to connect across communities and cultures, fostering empathy and broader perspectives. Psychologically, navigating different languages builds confidence, adaptability, and mental agility.
These benefits are cumulative: the more languages a person speaks, the greater the cognitive and health advantages. In a world where monolingualism is common in English-speaking countries, embracing bilingualism or multilingualism is not only a personal advantage but also a potential public health benefit, helping societies manage ageing populations more effectively.
Many languages the norm
Māori and Indigenous Education Professor Stephen May says that bilingualism and multilingualism are international norms. “While we can’t determine exact figures, we know that 50-75% of the world’s population speaks more than one language.
“And yet, most of those who speak English as a first language – again, up to 75% – are monolingual; they only speak English. So, these results on the positive cognitive and health effects of bilingualism and multilingualism, in any combination of languages, as we age, may come as a surprise to them.
“Indeed, what is most striking about the views of monolingual English speakers – both in Aotearoa New Zealand and elsewhere – is their often-entrenched negative views of bi/multilingualism and other language speakers.
“We see this most clearly in the overtly anti te reo Māori attitudes still prevalent in our society (and in current government policies) today. What is also striking about these lingering attitudes, apart from the fact that they are often highly racialised, is how spectacularly misinformed they are.
“In addition to the important enduring cognitive benefits in relation to ageing highlighted here, educational research over the last 80 years has also consistently highlighted the overall cognitive, social, and educational benefits of being bi/multilingual.
“So, the obvious question must be asked: when will monolingual English speakers finally realise that it is their inability and/or unwillingness to value, learn, and use other languages that is the real problem here…”
