Scientists have found that people who carry too much weight around their middle have smaller brains.
Researchers from Loughborough University and University College London found that people with a high body mass index (BMI) and high waist-to-hip ratio had brains that were 12 cubic cms smaller than people of a healthier weight.
Dr Mark Hamer, Professor of Exercise as Medicine, at Loughbourough, said it was unclear if the differences in brain structure were caused by obesity itself.
However, he concluded that the finding could explain why people who are overweight are more likely to develop dementia and other neurodegenerative diseases.
He said: "Existing research has linked brain shrinkage to memory decline and a higher risk of dementia."
"While our study found obesity, especially around the middle, was associated with lower gray matter brain volumes, it's unclear if abnormalities in brain structure lead to obesity or if obesity leads to these changes in the brain."