A type of disorder which is observed as an extreme pattern of dietary purity.

Orthorexia Nervosa is an eating disorder characterized by an obsessive fixation with eating only 'pure' and 'healthy' foods. Individuals with this condition become increasingly restrictive about what they eat, often eliminating entire food groups they deem impure. This is distinct from Prader-Willi (excessive appetite), Anorexia (calorie restriction), and Pica (non-food items).