A study by Paul Thompson, a researcher at the University of California, points out that obesity can reduce the size of the brain in the elderly , making them more vulnerable to dementia .
After analyzing 94 subjects who were over seventy years of age, Thompson observed that the brains of the obese appeared 16 years older "old" than that of their slimmer peers. Their results indicate that the elderly with a higher body mass index (BMI) also have a smaller brain, specifically 8% smaller than that of subjects with normal weight. And that the loss of brain mass occurs mainly in the temporal lobe and the frontal lobe , with an important role in planning and memory , respectively.
Thompson suggests that as body fat increases, clogged arteries are more likely, reducing oxygen and blood delivery to neurons in the brain. The good news, he adds, is that vigorous exercise can "save" the same amount of brain tissue that is lost to obesity. Their findings are published in the journal Human Brain Mapping .
