One in three cases of Alzheimer's disease worldwide is preventable, according to research from the University of Cambridge. The main risk factors for the disease are a lack of exercise, smoking, depression and poor education.
Previous research from 2011 put the estimate at one in two cases, but this new study takes into account overlapping risk factors. Alzheimer's Research UK said age was still the biggest risk factor.
Writing in The Lancet Neurology, the Cambridge team analysed population-based data to work out the main seven risk factors for Alzheimer's disease.
They worked out that a third of Alzheimer's cases could be linked to lifestyle factors that could be modified, such as lack of exercise and smoking.