The study challenges previous assumptions about dementia risks.

Obesity in midlife is associated with a greater risk of dementia down the road, a study that followed more than 1 million women for nearly two decades found.

The study refuted previous assumptions about the suggested link between increased risk of dementia and poor diet or lack of exercise. It involved one out of every four women born in the United Kingdom between 1935 and 1950. Their average age was 56 and they did not have dementia at the beginning of the study. 

Findings were published in the Dec. 18, 2019, online issue of Neurology.