Before their second round of scans, participants were asked to practice ignoring the food or shifting their thoughts away from it. During this phase of scanning, they were asked "to inhibit their desire for food and suppress their feelings of hunger."
That worked pretty well for the men. Their brain scans showed much less hunger-related activity when they tried to suppress their desire for food.
That didn't happen for the women, at least not as a group. Although some women were better than some men at suppressing food desire, overall the women's brains showed just as much hunger-related activity when they tried to hold down their desire.
Are the findings plausible? WebMD asked Rexford S. Ahima, MD, PhD, director of the obesity center at the University of Pennsylvania's Institute for Diabetes, Obesity, and Metabolism. Ahima is an expert in the brain circuits responsible for feeding behavior and body weight regulation.
"More and more we see there is a structural basis for why we eat the way we do. Maybe our brains are hardwired to predetermine the way we eat," Ahima says. "The interesting thing about the Wang study is that when they present food to people and ask them to consciously inhibit the urge to eat, men are better able to do it than women."
Ahima notes that the study only shows men to be better at inhibiting their brains' response to food. But can men really resist emotional eating better than women can? That, he says, will have to be tested directly.
Sex Hormones May Affect Hunger
Why do men's and women's brains respond differently? Wang and Ahima suspect that female sex hormones play a major role.
"There is a link between female hormones tending to promote weight gain and overeating," Ahima says. "There are some women who tend to binge eat in synch with their menstrual cycles. And look at pregnancy -- it makes some women overeat, but some do not. So while there may be overall differences in terms of gender, this may differ for individuals."
Wang suggests that women may have evolved to seek food more avidly than men do.