People who are overweight in their 60s are at higher risk of brain decline, a new study has found.
Researchers studied 250 adults aged between 60 and 70 and found those with a higher body mass index (BMI) and bigger waists performed more poorly in cognitive tests.
The participants had their BMI and waist measurements recorded and underwent an abdominal CT scan and a MMSE test to measure cognitive performance.
The Mini Mental State Examination (MMSE) test is the most commonly used test for complaints of memory problems or when a diagnosis of dementia is being considered.
The Korean study, published in the journal Age and Ageing, found that in those aged between 60 and 70, both a high body mass index (BMI) and large waist circumference were linked to poor cognitive performance.
However, in participants aged 70 and older, high BMI, waist circumference and abdominal body fat were not associated with low cognitive performance.
As well as BMI, the research also found a link between high levels of fat around internal organs and low cognitive function.
Professor Clive Ballard from the UK Alzheimer's Society said: "We have all heard how a high BMI is bad for our heart but this research suggests it could also be bad for the head. Although we don't know whether the people in this study went on to develop dementia, these findings add to the evidence that excess body fat could impact on brain function.
"One in three people over 65 will die with dementia but there are things people can do to reduce their risk. Eating a balanced diet, maintaining a healthy weight, exercising regularly and getting your blood pressure and cholesterol checked can all make a difference."
Alzheimer's Society research shows that 750,000 people in the UK have a form of dementia, more than half have Alzheimer's disease. In less than ten years 1m people will be living with dementia. This will soar to 1.7 million people by 2051.