Scientists from the University of Sheffield and the University of Eastern Finland compiled the research. The team stressed their study does not show that obesity causes Alzheimer’s but said people should think about exercising.
Professor Annalena Venneri, from the University of Sheffield’s Neuroscience Institute, said: “The diseases that cause dementia, such as Alzheimer’s and vascular dementia, lurk in the background for many years, so waiting until your 60s to lose weight is too late.
“Being overweight is an additional burden on brain health and it may exacerbate the disease.
“We need to start thinking about brain health and preventing these diseases much earlier.”