Speaking two or more languages helps protect your brain as you age, even if you learn new languages as an adult, new research suggests.
The study included 835 people born in Scotland in 1936 whose first language was English. They were given mental skills tests at age 11 and again in their early 70s. Of the participants, 262 were able to speak at least two languages, with 195 of them learning a second language before age 18, and the rest after that age.
Those who spoke two or more languages did much better on the mental skills tests when they were older than what would be expected from the tests they took when they were younger, especially in the areas of general intelligence and reading, the study authors found.
The positive effects of bilingualism were seen whether people learned new languages when they were children or adults, the researchers noted in the report published online June 2 in the journal Annals of Neurology.
According to study author Dr. Thomas Bak, from the Centre for Cognitive Aging and Cognitive Epidemiology at the University of Edinburgh, this study is the first to take into account for childhood intelligence while examining whether learning a second language affects mental skills later in life.
"These findings are of considerable practical relevance. Millions of people around the world acquire their second language later in life. Our study shows that bilingualism, even when acquired in adulthood, may benefit the aging brain," Bak concluded in a journal news release.
Although the study showed an association between learning a second language and having a sharper mind later in life, it was not designed to determine a cause-and-effect link between the two.
The findings provide "an important first step in understanding the impact of learning a second language and the aging brain," Dr. Alvaro Pascual-Leone, an associate editor for Annals of Neurology and a professor of medicine at Harvard Medical School, wrote in an accompanying commentary.