Is Your Brain Making You Obese?
Conducted by Dr. Nancy Puzziferri, assistant professor of surgery at UT-Southwestern, the study looked at brain scans of two groups of women — 15 obese and 15 lean — all of whom had eaten an identical meal and reported being full. The scans of the lean women showed no interest in food after the meal, but the brains of the obese women still lit up. She said the new findings should offer compulsive overeaters relief from the guilt that their eating habits are some kind of personal flaw.
“Before or after the meal, they’re just as excited about eating,” said Dr. Puzziferri in a news release. “It seems they have an instinctive drive to keep eating.”
Brain Still ‘Hungry’ After Meal
For the study, the women had fasted nine hours. They were then asked to rate their level of hunger or fullness and given a brain scan as they looked at pictures of food. Next, the women ate a standard meal, and, after eating, were again given the hunger/fullness test while in the MRI scanner. The resulting brain images showed that obese women continued to have “hungry” brain activation, even though they reported the same satisfaction after eating as the lean women.
Puzziferri later followed the obese women through weight-loss surgery. Six months after dropping weight, the women’s brain responses to food changed, resembling those of the lean women. But a year after surgery, their brains reverted to craving food, even after they were full. (Women were used for the study because 85% percent of gastric bypass patients are women.)
“Their brains started shifting back to their old stance, their old obese brain,” Puzziferri told today.com. “So it started becoming their enemy again. Their brains are still revved up and driving them to eat.”
What Does This Mean for the Obese?
Researchers don’t have all of the answers, such as whether the drive to keep eating is a conditioned response — meaning after years of eating a certain way the brain learns to respond differently — or if people are born with different brain activity. But Puzziferri says the message to those who are struggling with their weight is that it is going to be difficult, but not to give up. By acknowledging that the brain patterns are there, a person can work to combat the mind’s natural impulses.
What’s more, researchers hope to develop medications to counteract these cravings so obesity can be treated as a disorder of the brain, much like depression. Such a discovery would benefit an enormous number of Americans in light of the latest statistics from the Centers for Disease Control and Prevention that show that 36.5% of Americans are obese.
For her part, Puzziferri hopes her research will increase compassion for those who struggle to control their eating. “It’s just not a level playing field — it’s harder for some people to maintain a healthy weight than others,” she said. Bashing the obese only fosters the destructive thoughts and behaviors that characterize eating disorders from anorexia to obesity. And putting too much emphasis on weight rather than healthy eating and exercise can exacerbate eating disorders, experts say.
No eating disorder is a lifestyle choice. An eating disorder is a serious mental illness, born out of a range of emotions, including low self-esteem, a response to bullying or trauma, loneliness or depression. And without treatment, eating disorders can take over an individual’s life and lead to fatal medical complications.
The UT-Southwestern study appears in the journal Obesity.