BMI and Cognitive Function

From the Telegraph:

The new five-year study of more than 2,200 adults claims to have found a link between obesity and the decline in a person's cognitive function. The research, conducted by French scientists, which is published in this month's Neurology journal, involved men and women aged between 32 and 62 taking four mental ability tests that were then repeated five years later.

The researchers found that people with a Body Mass Index - a measure of body fat - of 20 or less could recall 56 per cent of words in a vocabulary test, while those who were obese, with a BMI of 30 or higher, could remember only 44 per cent.

The fatter subjects also showed a higher rate of cognitive decline when they were retested five years later: their recall dropped to 37.5 per cent, whereas those with a healthy weight retained their level of recall. ...

Dr Maxime Cournot, who headed the study, suggested that hormones secreted from fats could have a damaging effect on cerebral cells, resulting in decreased brain function. "Another explanation could be that since obesity is a widely known cardiovascular risk factor, due to the thickening and hardening of the blood vessels, that the same happens with the arteries in the brain," said Dr Cournot, an assistant professor in clinical epidemiology at Toulouse University Hospital.

Discuss as you wish.

Update: I see Shelley comments here.