obesity's effect on the brain

Posted on: Wed, 08/26/2009 - 21:17 By: Tom Swiss

HealthDay (at U.S. News & World report) reports on research on the link between obesity and the loss of brain tissue:

For every excess pound piled on the body, the brain gets a little bit smaller.

That's the message from new research that found that elderly individuals who were obese or overweight had significantly less brain tissue than individuals of normal weight.

"The brains of obese people looked 16 years older than their healthy counterparts while [those of] overweight people looked 8 years older," said UCLA neuroscientist Paul Thompson, senior author of a study published online in Human Brain Mapping.

Much of the lost tissue was in the frontal and temporal lobe regions of the brain, the seat of decision-making and memory, among other things.

...

The researchers studied brain images of 94 people in their 70s who had participated in an earlier study looking at cardiovascular health and cognition. None of the participants had dementia or other cognitive impairments. They were followed for five years, and any volunteers who developed cognitive symptoms were excluded from the study.

Clinically obese people had 8 percent less brain tissue, while the overweight had 4 percent less brain tissue compared to normal-weight individuals.

Dr. Jonathan Friedman, an associate professor of surgery and neuroscience and experimental therapeutics at the Texas A&M Health Science Center College of Medicine noted that the causal relationship here is not clear. Theoretically, he said, a smaller brain might mean appetite and weight-control centers of the brain are actually propelling the weight-gain process.

Thompson believes it may be a vicious cycle. "Each one is contributing to the other," he said. A person's genetics may be contributing to overeating and weight gain, which leads to less activity, which leads to a shortfall in the oxygen and nutrients that the brain needs to thrive and grow.

Connecting this finding with the parallel trends of the widening of the American ass and the rise of rank ignorance and anti-intellectualism in our social and political discourse, is left as an exercise for the reader...