Obesity in middle age is associated with an increased risk of dementia later in life, according to a study of more than 1 million women in the United Kingdom, reports HealthDay News.
Those who were obese in their mid-50s had 21% greater risk of being diagnosed with dementia 15 or more years later, compared with women who had a healthy weight, a team of British and international researchers found.
The study adds to the "ever-expanding body of data that says what you do with yourself in midlife -- and really even earlier -- affects your risk for dementia as you age," said Keith Fargo, director of scientific programs and outreach at the Alzheimer's Association in Chicago. He was not part of the research.
For the study, the researchers followed about 1 out of every 4 women born in the United Kingdom between 1935 and 1950, more than 1.1 million overall. Their average age at the start of the study was 56. None had dementia.
At the outset, researchers calculated each woman's body mass index (BMI), an estimate of body fat based on height and weight. They also asked about their diet and exercise. The women were followed for an average 18 years.
During that time, about 2.1% of obese women were diagnosed with dementia, compared to 1.6% of normal-weight women, the researchers found.