Speaking at Least Two Languages Keeps Dementia at Bay for at least 5 Years

The best way to keep dementia at bay is to speak two or more languages, according to a new study by the University of Edinburgh in Scotland.

People who were bilingual or multilingual developed dementia an average of 4.5 years later than those who spoke only one language, researchers wrote in the journal Neurology.

The researchers reviewed the case histories of 648 people with dementia; 391 of them were bilingual. The people lived in Hyderabad, India -- interesting because much previous work in this area has been with immigrants, who bring a native language to a new culture. Most people in Hyderabad are at least bilingual. They are exposed to Telugu and Dakhini languages in informal contexts, such as home, and to Hindi and English in school and other formal contexts.

"Our study is the first to report an advantage of speaking two languages in people who are unable to read, suggesting that a person's level of education is not a sufficient explanation for this difference," study author Dr. Suvarna Alladi, a researcher at Nizam's Institute of Medical Sciences in Hyderabad, India, said in a journal news release. "Speaking more than one language is thought to lead to better development of the areas of the brain that handle executive functions and attention tasks, which may help protect from the onset of dementia."

The study, titled "Bilingualism Delays Age at Onset of Dementia, Independent of Education and Immigration Status," took place among 648 dementia patients in the Indian city of Hyderabad, a cultural melting pot where much of the population speaks two or more languages regardless of class or education level. The average age of participants was 62.2 years. Slightly more than half the study participants spoke two or more languages.

Regardless of education level, gender, occupation, or urban or rural living, researchers discovered that bilingual people developed dementia an average of four and a half years later than monolingual ones. These results were independent of whether a person could read or not.

There was no added benefit in speaking more than two languages, the researchers pointed out.