BEING overweight may have a direct link to reduced intelligence, a controversial study suggests.
Scientists claim school pupils with a high body mass index performed worse in tests.
Scans also showed the outer layer of their brain was thinner, especially in an area linked to memory and decision-making.
But it is not clear if a poor diet harmed brain development or if an under-developed brain caused over-eating.
Experts say the two may interact — or the link may just be coincidence.
Dr Jennifer Laurent, from the University of Vermont, US, analysed the scans and exam results of 3,190 children aged nine and ten.
She said: “These findings suggest BMI is associated with alterations in prefrontal cortex development and diminished executive function.
“Deficits in working memory may contribute to poor dietary decisions.
“Once established, these associations may become mutually reinforcing and contribute to ongoing health issues that persist into adulthood.”
Prof Naveed Sattar, from the University of Glasgow, said: “This paper is provocative but it cannot be taken as saying excess weight causes these memory or brain differences.”
One in five children in England is overweight or obese when they start primary school, rising to one in three by the time they leave.
Overweight kids are more likely to be obese in adulthood, which increases the risk of heart disease, cancer and type 2 diabetes.
