Science Magazine recently published findings from a study on obesity and the pleasures of eating. What they found was that overweight people do not get the same amount of pleasure or, in scientific terms, their striatal response is blunted. Huh?
According to the study, "dorsal striatum plays a role in consummatory food reward."
Fortunately, Very Short List has a friendly translation. A part of the brain has a pleasure response that relates to the number of dopamine receptors. Obese women have fewer of these receptors, meaning they get less pleasure from the same amount of food.
An obese person will derive less pleasure from a scoop of ice cream than a thinner person. So it takes more ice cream to provide the same amount of satisfaction to an obese person. Consequently, the obese person will eat more in order to compensate and feel better.