Stimulation: the Battle for Your Mind

Reduced response to high-calorie food can reduce weight

Scientists have revealed that an anti-obesity drug changes the way the brain responds to appetising high-calorie foods in obese individuals. This may aid the development of new anti-obesity drugs that reduce activity in regions of the brain stimulated by the sight of tasty foods.

Professor Paul Fletcher from the University of Cambridge, one of the paper’s authors, said, “Our findings suggest we may be able to use brain imaging and psychological tests to make better predictions of which drugs are likely to work.”

Using functional magnetic resonance imaging, the researchers measured brain activity while obese subjects viewed pictures of high-calorie foods like cake, or low-calorie foods like broccoli. The scanning took place both after two weeks of treatment with anti-obesity drug sibutramine, and two weeks of placebo treatment.

On placebo, simply seeing pictures of appetising foods caused greater activation of brain regions important for reward processing. On sibutramine, there were reduced responses to appetising foods in the hypothalamus and amygdala, important in appetite control and eating behaviour. People who had the greatest reduction of brain activation ate less and lost more weight.