Women Less Able to Suppress Food Desire, Study Suggests
"Women have a much stronger reaction to food, such that whether they try to inhibit their desire or not, they have stronger signal [in the part of the brain that controls hunger perception and desire to eat]," study leader Gene-Jack Wang, MD, tells WebMD.
Wang, chairman of the medical department of Brookhaven National Laboratory, Upton in N.Y., and colleagues have been using state-of-the-art brain imaging to learn which parts of the brain are involved in eating behaviors.
They have previously shown that obese people are less able than others to sense when their stomachs are full. Recently, they have looked at what happens in the brain when a hungry person gets to see, smell, and taste -- but not eat -- favorite foods.
In some of these studies, they saw very strong signals in parts of the brain involved in emotional regulation and motivation. But in other studies, the signals weren't so strong. Wang suspected this might be because of differences between how men and women react to food.
So they tested 13 women and 10 men with PET brain scans. To make sure they were hungry, study participants fasted for 18 hours before scanning. And to make sure they were tempted, the researchers made the participants' favorite foods: bacon/egg/cheese sandwiches, cinnamon buns, pizza, cheeseburgers, fried chicken, lasagna, barbecued ribs, ice cream, brownies, and chocolate cake.
During scanning, participants were able to see and smell the food. They even got tastes, applied to their tongues with a cotton swab. To make sure they stayed tempted, researchers brought them new hot food every four minutes.
But subjects didn't get to eat until the 30-minute scans were completed, and only after they completed a quiz on their feelings of hunger, desire for food, and alertness.