People must maintain social interactions as they enter old age, a leading social care charity has warned, as new research suggests a link between loneliness and Alzheimer's.
The US study of more than 800 older people found those who are lonely are more than twice as likely to develop Alzheimer's disease.
The study was led by neuropsychology professor Robert Wilson and was based on questionnaires over a four year period.
Writing in the Archives of General Psychiatry, Professor Wilson from Rush University Medical Centre said: "There are two ideas that we should take away, number one is it suggests that loneliness really is a risk factor and secondly in trying to understand that association we need to look outside the typical neuropathology."
Counsel and Care spokeswoman Elizabeth McLennan stressed the need for older people to reduce feelings of isolation for their own sake.
"Interaction with other people exercises your brain," she said.
"If you talk to people then you have to concentrate on what people are saying, that in itself exercises your mental faculties. I guess it’s not entirely surprising [that there could be a link between Alzheimer's and loneliness].
"If it increases wellbeing and also reduces your chance of getting Alzheimer's then that’s a great by-product. Social isolation needs to be reduced for its own sake as well – and loneliness and things like that just for the wellbeing of the person. Any health benefits are an added extra."