“FED NOS” stands for “Feeding or Eating Disorder Not Otherwise Specified.” In the context of eating disorders, this term was used in previous editions of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) to categorize eating disorders that did not meet the specific criteria for anorexia nervosa, bulimia nervosa, or binge eating disorder.

The DSM-5, has replaced the term “Feeding or Eating Disorder Not Otherwise Specified” with “Other Specified Feeding or Eating Disorder” (OSFED) and “Unspecified Feeding or Eating Disorder” (UFED). These changes were made to provide more specific diagnostic criteria and to better capture the range of symptoms and presentations seen in clinical practice.

Other Specified Feeding or Eating Disorder (OSFED) includes individuals who have symptoms of an eating disorder that cause significant distress or impairment but do not fully meet the criteria for anorexia nervosa, bulimia nervosa, or binge eating disorder. Examples include atypical anorexia nervosa (where a person meets all criteria except for weight), subthreshold bulimia nervosa (where binge eating or compensatory behaviors occur less frequently), and purging disorder (where a person engages in purging behaviors without binge eating).

Unspecified Feeding or Eating Disorder (UFED) applies to cases where symptoms characteristic of an eating disorder cause significant distress or impairment but do not fit into any specific category or where there is insufficient information to make a more specific diagnosis.

These categories under OSFED and UFED are important because they acknowledge that eating disorders can vary widely in presentation and severity, and individuals may still need treatment and support even if they do not meet the strict criteria for the main diagnostic categories. Treatment for OSFED and UFED typically involves similar approaches as those used for the more recognized eating disorders, including psychotherapy, nutritional counseling, and in some cases, medication.