Genetic Epidemiology and Risk Factors of Formal Eating Disorders

By: Susan Parish-Walker, M.S., L.P.C.

In regards to eating disorders, the possible role of hereditary factors has not been without historical precedent. As early as 1860, Louis Victor noted that inherited psychopathologies were prominent in families of young women with anorexia nervosa, and that the rearing environment was often disturbed.  More recently, reports of peculiar feeding habits in families are evident.  For example, it is not uncommon for family members to have a history of trying a myriad of diets such as Atkins or South Beach diets. Certain genetic factors may also contribute to comorbidity diagnoses and influence the risk of both major depression and bulimia nervosa.  Although there are higher prevalence rates of substance use and abuse among patients with eating disorders who engage in binge episodes, the  following are also critical factors that may lead to bulimia nervosa:  (1). premorbid dieting and related risk factors (i.e., critical comments by the family regarding body shape or weight); and (2). general risk factors for psychiatric disorders.There is also a genetic component that increases the risk for developing anorexia nervosa.  A predisposition for having a low body weight or percentage of adipose tissue (body fat), may play a role. Moreover, genetic predispositions are clearly apparent with the personality traits of a patient who has developed anorexia nervosa. These personality traits include higher IQ than the normal population, perfectionism, obsessionality, negative self-evaluation, and overly compliant. Other risk factors that may contribute are psychiatric disorders and childhood adversity such as physical or sexual abuse or death of a close relative. In addition, there is a lack of research on the risk factors for binge eating disorder, but adverse childhood experiences, potential for obesity, and repeated derogatory comments about one’s weight, shape, or size appear to contribute.

It is suggested that the increased vulnerability of high risk groups may stem from the sociocultural pressure to be thin.  Highly competitive people develop a relentless pursuit to be thin to enhance their performance and aesthetic appeal. Therefore, sports or extracurricular activities that may require weight restriction such as lightweight rowing, wrestling, volleyball, distance running, gymnastics, ballet, and figure skating may fall into this category as risk factors.

In closing, the growing need for more research on family systems may need to be examined to identify genetic factors.  Currently, more organizations and wellness programs are educating participants on the risk factors of developing an eating disorder as a means of prevention.  The need for more mental health professionals, dietitians, and other healthcare professionals to be educated on assessing the early symptoms of disordered eating is essential to prevention. With prevention and early detection, the disordered eating may be kept from developing into a full blown eating disorder.