Eating Disorders in the News: Anorexia Nervosa vs. Constitutional Thinness
Anorexia nervosa is characterized by the intense fear of gaining weight, a distorted body image, inability to maintain a minimally normal weight and extreme dietary habits that prevent weight gain such as food restriction, excessive exercise or purging behaviors. There are two subtypes of anorexia nervosa known as the restricting type and the bing-eating/purging type. Most individuals associate anorexia with the restricting subtype, which is characterized by the severe limitation of food as the primary means to lose weight. The second subtype is known as binge-eating/purging subtype which is characterized by periods of binging followed by self-induced purging behaviors such as vomiting, diuretic abuse, laxative abuse or excessive exercise. Anorexia nervosa is a clinical diagnosis, like most mental health disorders, meaning that there is no specific laboratory test or imaging study that can confirm the diagnosis. Constitutional thinness is an underweight state with no changes in eating behaviors. Low weight is the only similarity between constitutional thinness and anorexia nervosa however recently a study released out of Europe, showed that blood levels of a thyroid hormone can be used to distinguish the two conditions with high sensitivity and specificity.
