"These results suggest that dieting not only increases stress, making successful dieting more difficult, but that it may actually 'reprogram' how the brain responds to future stress and emotional drives for food," said study co-author Tracy Bale of the University of Pennsylvania, in a news release."
http://www.latimes.com/health/boostershots/la-heb-yo-yo-diet-20101130,0,4227680.story