When hungry, the hormone ghrelin is produced in the stomach. In a new study conducted on rats at Sahlgrenska Academy, University of Gothenburg, the hormone has been shown to have a negative effect on decision making capabilities and impulse control. "For the first time, we have been able to show that increasing ghrelin to levels that are seen prior to meals or during fasting, causes the brain to act impulsively and also affects the ability to make rational decisions," says Ka