London: Piling on the pounds in middle-age makes for greater chances of developing Alzheimer`s -- as high as 80 percent.
The latest evidence shows maintaining a `healthy` weight or losing the spare tyre is the best way to avoid an increased risk of mental decline in later years.
Researchers in Sweden concluded that middle-age spread could lead to memory problems after analysing information spanning 30 years on 8,500 twins aged 65 and over.
Study author Weili Xu, Karolinska Institute in Stockholm, said half of adults in European countries such as Britain could be at risk because they were overweight or obese, the journal Neurology reports.
"Our results contribute to the growing evidence that controlling body weight or losing weight in middle age could reduce your risk of dementia," Xu said, according to the Daily Mail.
The conclusions duplicate evidence two years ago from a US review of 10 international studies involving more than 37,000 people, pointing to obese people having an increased risk of all types of dementia.
Experts do not know exactly why obesity affects the risk of dementia, although hardening of the arteries and high blood pressure play a role.
New dementia treatments could be available in 10 years using six drugs already available for other conditions, says the Alzheimer`s Society.
Its chief executive Jeremy Hughes said the drugs are not being named because further evidence is needed to show they work and so that people do not try to use them before they have been tested properly.