The ability to speak more than one language can delay the onset of dementia by up to five years, it has been claimed.
Canadian researchers at the Baycrest Rotman Research Institute examined the record of more than 200 patients diagnosed with Alzheimer's disease, according to an article in the latest edition of the Neurology journal.
It was found that those people who spoke two or more languages on a regular basis over many years delayed the onset of the disease.
Lead author Dr Fergus Craik said that while it cannot be claimed that speaking two languages will prevent dementia, this suggests it does add to the cognitive strength of the brain.
"There are currently no drug treatments that show any effects on delaying Alzheimer's symptoms, let alone delaying the onset of these symptoms by up to five years," added co-author Dr Morris Freedman.
According to the Alzheimer's Research Trust, combined government and charitable investment in dementia research is 12 times lower than spending on cancer research.
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