Anorexia and Bulimia: Cracking the Genetic Code
New research suggest a person's genes may point to a propensity for developing an eating disorder.
Anorexia Genes continued...
Many people have theorized that the current obsessive cultural focus on weight and thinness -- and on celebrities and their appearances -- is likely to promote anorexia and bulimia. But that doesn't entirely explain the conundrum of eating disorders, says Johnson.
"The overall prevalence of anorexia and bulimia, combined, is about 4%. But if they're largely caused by societal pressures, there should be a lot more of this. How many newsstand magazines can you pick up and read about someone's weight loss?" he asks. "Why can many girls go on a diet and walk away not dramatically affected, while four out of 100 wind up with psychiatric illnesses? The answer probably lies in neurochemistry and genetics."
The genetic research seems to indicate that some people -- mostly, though not all, female -- may have a latent vulnerability to eating disorders, which might never be "turned on" if they weren't exposed to particular influences, just as a predisposition to alcoholism can remain latent unless the person takes a drink.
"Since in our culture today, dieting behaviors are more intense, it's exposing that latent vulnerability more now than in previous generations," suggests Johnson.
Treating Anorexia as a Genetic Disorder
Ultimately, of course, the investigators hope that this research might suggest new possibilities for treatment.
"The long-term goal is to identify those aspects of brain-related function that influence development, behavior, and personality, and help us refine the search for potentially more effective pharmacotherapies," says Michael Strober, MD, professor of psychiatry at the David Geffen School of Medicine at the University of California, Los Angeles. He is also director of the Eating Disorders Program at the Lynda and Stewart Resnick Neuropsychiatric Hospital at UCLA.
But while new medicines may help, Strober is quick to say he doubts anorexia and bulimia will ever be treated solely with medication. "More effective new medications will be important, but a combination of approaches is essential. The importance of psychotherapy should never be minimized."
Drug treatments based on the new research are probably a long way off. But in the meantime, study results may help improve current treatment approaches. "It potentially gives us a frame of reference for psychological treatment, allowing us to better target the therapeutic approaches that may help," says Strober.
Information about the inheritability of anorexia and bulimia will also be important in prevention. For example, it could help parents and doctors to intervene early with young people whose family history and psychological profile may put them at particularly high risk. Johnson says that studies have shown people at highest risk for anorexia or bulimia tend to have five personality traits:
Many experts also hope that the growing evidence for a genetic component to anorexia and bulimia will help make the case for better access to treatment of these disorders, and improved insurance coverage of such treatment.