I wonder if they were using their brains while conducting this study? From the short article there isn’t enough information to say anything regarding weight and the brain. All they did was take measurements six years apart. There is no way to know what these people did in between the time the measurements were taken. Seems like a rather worthless study to me unless it motivates people to shed some pounds.
About 27% of participants had a BMI of less than 25, which is considered normal, while 44% were classified as overweight and 29% were labeled as obese. People with higher BMIs had thinner cortexes, even after adjusting for various factors, including high blood pressure, alcohol use and smoking, the study found. Having a bigger waist size was also associated with a thinner cortex.Marketwatch.com