Anorexia is a decreased appetite. While the term in non-scientific publications is often used interchangeably with anorexia nervosa, many possible causes exist for a decreased appetite, some of which may be harmless, while others indicate a serious clinical condition or pose a significant risk.
Anorexia is a symptom, not a diagnosis. When a healthcare provider states that a patient has anorexia, they are simply referring to a decreased appetite. This means that the provider must find and treat the underlying cause of the anorexia. Anorexia is not to be confused with the mental health diagnosis, anorexia nervosa. Because the terms are commonly used interchangeably, a provider must clarify to a patient to which they are referring as to avoid confusion. Anyone can manifest with anorexia regardless of their gender, age, or weight.
The term is from Ancient Greek ανορεξία: 'ἀν-' "without" + 'όρεξις', spelled 'órexis' meaning "appetite".
In Chinese medicine, lack of appetite ususally signifies a stomach or spleen disharmony due to deficient qi or dampness.