What eating disorder is associated with a progressive loss of appetite leading to weight reduction beyond healthy levels?

Anorexia nervosa is characterized by an intense fear of gaining weight and a distorted body image, which leads to restrictive eating and an extreme reduction in food intake. This disorder often results in significant weight loss, as individuals with anorexia have an extreme preoccupation with food, body weight, and dieting. The progressive loss of appetite and refusal to maintain a healthy body weight are hallmarks of this condition, making it distinct from other eating disorders.

Binge eating disorder involves recurrent episodes of eating large quantities of food, often leading to feelings of loss of control, but it does not primarily focus on weight loss and actually leads to weight gain rather than reduction. Bulimia nervosa is characterized by cycles of binge eating followed by compensatory behaviors, such as vomiting or excessive exercise, which again differs from the progressive loss of appetite seen in anorexia nervosa. Orthorexia involves an unhealthy obsession with eating only 'pure' or 'healthy' foods, which can lead to a restrictive diet but does not necessarily include the same severe weight loss and fears characteristic of anorexia. Each of these disorders has unique features that differentiate them from anorexia nervosa.