In the diagnosis of eating disorders, how do anorexia nervosa and bulimia nervosa primarily differ in terms of body weight?

• A. Anorexia nervosa is typically associated with underweight BMI; bulimia nervosa usually has normal to overweight body weight.
• B. Anorexia nervosa always includes binge eating.
• C. Anorexia nervosa is typically associated with underweight BMI, while bulimia nervosa is often underweight.
• D. Both disorders never involve weight concerns.

Answer: (C)

The key idea here is how body weight appears in these two disorders. Anorexia nervosa is characterized by significantly low body weight for age, sex, and developmental stage, so individuals are usually underweight. Bulimia nervosa, by contrast, typically presents with normal weight or overweight; bingeing and purging can occur without a markedly low weight, and many people with bulimia maintain a normal or higher body weight.

That contrast is why the best answer is the one that links anorexia with underweight and bulimia with normal to overweight weight. The other statements don’t fit what clinicians commonly see: underweight isn’t a defining feature of bulimia, and weight concerns are present in both disorders rather than being absent.