Eating Disorders May Run in Families
Anorexia is not a common mental health disorder, but there are clear diagnostic markers for recognizing it, according to the Diagnostic and Statistical Manual of Mental Health. These are:
- The person is below 85 percent of normal weight
- The person exhibits extreme concern about their weight despite being underweight
- The person places a disproportionate importance on body shape and weight when measuring their own self-worth
- The person experiences a three-month disruption in menstrual cycle
- The person shows no evidence of subtypes, e.g. restriction or binge/purge
The fact that persons with anorexia share several personality traits points to a genetic underpinning. Some of those traits include perfectionism, obsessiveness, anxiety and harm avoidance. There are also some common mental health problems. These often show up before the eating disorder and frequently persist once eating becomes normalized. Common mental health issues include anxiety disorder, major depression and obsessive compulsive disorder (OCD).
Whether genetics or environment play a more dominant role seems to vary from person to person and this can make effective treatment a little hit and miss. A Swedish twin study working with over 31,000 twins did reveal that anorexia is linked to some of the same heritable traits associated with other addictions. The twin study found that anorexia was 56 percent heritable and otherwise attributable to environment.
Whether genetic or environmentally-triggered, anorexia has some common risk factors. These include gender (most sufferers are female), childhood neuroticism and food issues, sexual abuse, psychiatric disorders, negative self-image and family history. While not considered risk factors, other warning signs of anorexia can include excessive exercise, digestive or stomach problems, extroversion, emotional instability and perceived stress.
Another clue that the disorder is genetically tied is that immediate family members run a 6 to 10 times greater risk of developing anorexia than do people in families where no anorexia is present. Even if the immediate family members do not develop anorexia, they are still at risk for an eating disorder not otherwise specified (EDNOS). Furthermore, in families where anorexia was treated, the risk for bulimia in future years is high.
The difficulty in separating out root causes is pronounced when it comes to eating disorders. For example, is extreme dieting a risk factor for developing anorexia or is it an early symptom? Experts still cannot say for sure. Similarly, there is strong evidence that genetics play a major role in the illness, but how genetics interact with strong environmental factors differs from person to person. Again, this makes it very difficult to determine which element is most influential.