How genetics play a role in eating disorders

The after-school TV specials of the 1980s got it wrong — eating disorders do not only affect teen girls and are not caused by peer pressure, diets and women’s fashion magazines. In fact, eating disorders affect people of every age, gender, race and socioeconomic group. A recent study found that biology and family history play a key role in determining a person’s risk for developing anorexia nervosa or bulimia.

Anorexia — characterized by self-starvation and excessive weight loss — and bulimia — marked by binge eating and purging — are psychiatric disorders with high mortality rates. Understanding their cause is necessary to successfully identify and treat the estimated 30 million Americans with eating disorders. More than 20 million women and 10 million men meet the criteria for an eating disorder at some time in their lives.

Genes play more of a role in eating disorders than previously thought
Through the study of twins and the genes of people diagnosed with an eating disorder, researchers have been able to establish that eating disorders are 50 to 60 percent heritable. This means that there is a genetic predisposition for the illnesses — a change in people’s genes makes them susceptible to eating disorders, just as some people are predisposed to cancer, heart disease and addiction.

“In the past, it was believed that eating disorders, such as anorexia or bulimia, were personal choices or caused only by social or environmental influences,” says Linda Santangelo, PhD, lead clinical psychologist at the eating disorders program at Sharp Mesa Vista Hospital. “However, we now know that there are numerous contributing factors that lead to their development.”

Risk factors for eating disorders
Along with genetics, Dr. Santangelo says the risk factors for eating disorders encompass a variety of additional biological, psychological and sociocultural issues. These include the following:

• Negative energy balance — calories consumed is less than calories burned

• Perfectionism

• Harm avoidance or aversion to risk

• Anxiety disorder

• Cultural weight stigma and internalization of the “thin ideal”

• Teasing or bullying

• Trauma

• Type 1 diabetes

Understanding that the illness is neither a choice, nor due to a personality deficit or bad parenting, can relieve sufferers — and their families — from the shame, guilt, blame and stigma that often surrounds eating disorders and other mental health conditions.

Help is available for those with eating disorders
“Much like we wouldn’t blame someone for a cancer diagnosis, we can help patients with eating disorders and their loved ones understand that there are biological roots to their condition,” Dr. Santangelo says. “Eating disorders are treatable and people do recover. Understanding how eating disorders develop, the role an individual’s personal risk plays, their specific symptoms, and any co-occurring mental and physical health conditions is the first step in creating a treatment plan to help them get better.”

Talk with your doctor if you or a loved one are concerned about disordered thoughts or behaviors related to food. Sharp Mesa Vista Hospital offers a specialized eating disorders treatment program.

For the news media: To talk with Dr. Linda Santangelo about the genetic component of eating disorders for an upcoming story, contact Erica Carlson, senior public relations specialist, at erica.carlson@sharp.com.