Those campaigning to scrap the compulsory retirement age have discovered another reason for older employees to stay in work: this time, with the news that working beyond retirement can delay Alzheimer’s disease.

It was believed that keeping the brain active can help postpone or perhaps even prevent dementia, of which alzheimer’s disease is the most common type, and British scientists at the Institute of Psychiatry at King’s College London have confirmed that keeping the brain active by working later in life reduces the risk of developing Alzheimer’s disease at a younger age.

The study was funded by the Alzheimer’s Research Trust. Scientists analysed data from 1,320 people with dementia, considering education, employment and retirement. The research, published in the International Journal of Geriatric Psychiatry, found no link between education or employment and dementia risk, but found those who retire later prolong their mental abilities above the threshold for dementia.

Professor Simon Lovestone, Scientific Adviser to the Alzheimer’s Research Trust and the paper’s co-author, said: “The intellectual stimulation that older people gain from the workplace may prevent a decline in mental abilities, thus keeping people above the threshold for dementia for longer. Much more research is needed if we are to understand how to effectively delay, or even prevent, dementia.”

Rebecca Wood, Chief Executive of the Alzheimer’s Research Trust, which funded the study, said: “More people than ever retire later in life to avert financial hardship, but there may be a silver lining: lower dementia risk. Much more research into lifestyle factors is needed if we are to whittle down the £17 billion a year that dementia costs our economy.”

These findings are not only good news for business, who have another good reason to keep on willing workers past retirement age, but employees too, as 700,000 people currently have dementia, but this a number set to double in a generation.