Getting at underlying factors of eating disorders

Subtle differences in brain activity may be the key to unlocking the cause of eating disorders and lead to a more proactive approach in tackling the disease.

By looking at the disease both biologically and psychologically, Psychology professor Lindsay Bodell, hopes to uncover the factors that make certain individuals more vulnerable than others to display eating-disorder behaviors.

"One of the things I'm looking at is can we see brain-based differences in terms of response," said Bodell, Director of the Psychobiology of Eating And Related Disorders (PEAR) Lab. "How people react to social evaluation—whether it's positive or negative—can we see differences at a neurological level? Does that impact the risks for more likely developing such disorders?"

While everyone sees and hears these same messages around body image and the need to lose weight, Bodell questions why not everyone engages in behaviors such as anorexia, bulimia or binge eating as a result of those same messages.

"There is some sort of biological vulnerability paired with some kind of environmental input and that, together, makes the diagnosis not that simple," she said.

One of Bodell's current studies is comparing youth with and without eating disorders to see if they differ in terms of how their brain reacts to social feedback. Determining this is a first step in developing better ways to understand the precursors to eating disorders, she said, and creating opportunities to be proactive in dealing with the disease

General risk factors, such as depression or anxiety, may be an early precursor to engaging in disorder eating behaviors.

"They might turn to some type of eating disorder patterns as a way to have control over something or a way to calm their anxieties," Bodell said. "They feel a sense of calmness and it may help decrease some of that anxiety, which may then lead to the continuation and extension of some of these eating behaviors.

"They are not engaging all the time, maybe once or twice a week. So it's trying to understand what those momentary factors are that are setting it off. That is important for the treatment. If we can identify when and why, then there is potential to develop treatment that specifically targets these processes."

Bodell said even those not expected to have an eating disorder could become susceptible to triggering eating-disorder behaviors, simply by jumping on the latest diet fad.

When food intake is restricted, emotional and chemical imbalances are activated. Those have the potential to lead to unhealthier and more extreme eating later on in the diet.

"Dieting is one of the biggest factors for the onset of eating disorders," said Bodell, referring to such weight loss measures as intermittent fasting or avoiding carbohydrates and fats. "When we look at these extreme forms of dieting, it often looks similar to the types of behaviors people are engaging in with eating disorders."

Bodell looks at what's referred to as "weight suppression"—people who have lost weight but are still within a healthy weight range. Higher levels of weight suppression can become a risk factor for the onset of binge-type or bulimic-type eating disorders, she added.

"As we lose weight and body fat, our leptin levels decrease, which essentially sends a signal to the brain saying you need to start eating," added Bodell of the hormone that helps regulate body weight and eating habits. "This lower leptin can then be related to binge-eating behaviors."

Psychological factors around dieting can also play a role, with many people receiving positive feedback from peers on their new appearance.

"Maybe people who are getting a lot more of this positive reinforcement are then starting to feel they need to maintain this weight in order for them to be appreciated and valued," Bodell said. "That can put them through this psychological process of "I need to maintain this weight' – and then they become even more preoccupied with that internal drive for thinness. The mind is telling you one thing; the body is telling you another. You get stuck in this repeated pattern of overly restricted eating and then binging, as well."