Scientists in India have found more evidence that people who speak two languages ​​are less likely to develop dementia compared to people limited to one language. "The prevalence of dementia was higher among monolinguals (4.9 percent) than bilinguals (0.4 percent)," according to scientists from the National Institute of Mental Health and Neuroscience, whose work was published in the journal Alzheimer's and Dementia. " Previous research has suggested that being polyglot may mean a lower probability of cognitive decline later in life, but the previous finding lacked "much evidence from community-based studies," the team of scientists said in the paper. They tried to fill the gap by going door-to-door in Bangalore, a city in southern India known as the country's information technology hub, where they found that the prevalence of mild cognitive impairment “was also higher in monolinguals ( 8.5 percent) than in bilingual (5.3 percent)".

In 2023, a team based in Germany published a paper in the journal Neurobiology of Aging, in which they wrote that bilingualism in early life means a reduced risk of dementia in later life. In 2014, scientists from the University of Edinburgh suggested that speaking more than one language could have a 'protective effect' on the brain. However, it is not just the ability to speak a language that can help against dementia, according to another recent study. There may be a link between diabetes and the likelihood of developing dementia, according to research presented at the March 23-26 annual meeting of the American Society for Biochemistry and Molecular Biology. Research from the University of California published in early 2024, however, suggests that good sleep at a young age reduces the risk of dementia. In mid-2023, a team in Switzerland found that the aging brain benefits from listening to music, while at the same time, research by New York University doctors found that moderate internet use in the elderly can help fight of cognitive decline. Hearing and vision decline were separately associated with a greater probability of developing dementia.