You think so? Think again!

Scientists at the Oregon Research Institute compared the brain responses of skinny and overweight people while drinking a milkshake. It turned out that a brain region called dorsal striatum, which the scientists describe as “a dopamine-rich pleasure center” became active. However, that brain region was less active in overweight people than in lean people.

Previous brain scans have already shown that overweight people have fewer dopamine receptors that normal weight people. This difference seems to be caused by genetics.

One of the senior scientists at the Oregon Research Institute concludes, based on the study results, that opposed to common belief obese people get in fact LESS satisfaction from food and to compensate for that they eat more.

More: Oregon Research Institute

In an experiment, the researchers compared the feeding pattern of socially dominant female rhesus macaques and socially subordinate. The subordinates were exposed to more stress because rhesus macaques maintain group stability through continual harassment and threat of aggression against lower ranking group members.

During the study, the rhesus macaques were given access to a low fat diet and a high fat diet. The researchers found that socially subordinate females consumed significantly more of both the low-fat diet and the high-fat diet throughout a 24-hour period, while socially dominant females ate significantly less than subordinate animals and restricted their feedings to daytime hours.

Result: Overeating subordinate females gained weight. In addition, the researchers found an increased level of the hormone cortisol in their blood, which could set them on the track to diabetes.

In further studies, the researchers will attempt to determine whether there is a link between brain areas associated with reward and satisfaction and appetite signals. Hypothetically, it could be that we are kind of “programmed” to eat more when we are under psychological stress, and then, for a “stress eater” it will be much harder to stick to a diet.

Read more: http://www.whsc.emory.edu/press_releases2.cfm?announcement_id_seq=14225